WO2025194971A1 - Carnot heat engine and carnot heat pump - Google Patents

Abstract

A heat engine, comprising a cylinder, wherein the cylinder comprises a working medium gas; the outer wall of the cylinder is of an integrated totally-closed structure, and can effectively prevent the working medium gas in the cylinder from leaking out of the cylinder; the cylinder can move and can output power by means of movement; the cylinder comprises a mechanical energy piston. Further disclosed is a heat pump having the same structure as that of the heat engine. The heat engine and the heat pump can improve the efficiency, save energy, reduce waste gas emission, and reduce environmental pollution, so that the global economic development is more efficient and more sustainable.

Description

Carnot heat engine and Carnot heat pump Technical Field

The present invention relates to the field of heat engines/heat pumps, and in particular to a Carnot heat engine/heat pump.

Background Art

A heat engine converts internal energy into mechanical energy. Operating between a high-temperature heat source (T1) and a low-temperature heat source (T2), a heat engine absorbs heat from the high-temperature heat source and releases heat to the low-temperature heat source during each operating cycle, while simultaneously performing external work.

The Carnot cycle is the most efficient heat-to-work conversion cycle, with a theoretical efficiency of 1-T2/T1. A Carnot heat engine is a heat engine whose working cycle is the Carnot cycle.

The Carnot cycle is a reversible cycle consisting of a series of reversible processes in the working gas within a heat engine. These reversible processes include isothermal expansion, adiabatic expansion, isothermal compression, and adiabatic compression. The isothermal process also involves the simultaneous change of the working gas temperature and the heat source temperature.

A Carnot heat engine operating in reverse becomes a heat pump. Its function is to absorb heat from a low-temperature heat source by receiving work from the outside world and then release the heat to a high-temperature heat source. The reverse Carnot cycle is also the most efficient heat pump operation method.

Currently, there are no heat engines or heat pumps that truly operate using the Carnot cycle. At the same T1 and T2 temperatures, the theoretical efficiency of other cycles is no higher than that of the Carnot cycle. Most common heat engines have lower theoretical efficiencies than the Carnot cycle.

The Stirling and Ericsson cycles are two theoretically efficient cycles that rival the Carnot cycle. However, heat engines and heat pumps based on these cycles have significant drawbacks, limiting their application. These drawbacks primarily include: 1. Both rely on ideal heat exchangers to achieve the efficiency of the Carnot cycle; 2. The Stirling engine's enclosed working fluid is separated from the outside world by a piston, which can easily lead to working fluid leakage during piston movement due to insufficient airtightness, while an overly tight piston increases resistance to movement; and 3. The Ericsson engine requires a large gas storage chamber.

A heat exchanger is a device that allows two gases to exchange heat. When a high-temperature gas (T1) and a low-temperature gas (T2) pass through the same heat exchanger simultaneously, the high-temperature gas cools down while the low-temperature gas warms up. An ideal heat exchanger would cool the high-temperature gas down to T2 and raise the low-temperature gas to T1, effectively exchanging the two temperatures. Actual performance can achieve up to 90% of the ideal value. Therefore, the actual efficiency of Stirling and Ericsson engines is lower than that of the Carnot cycle.

Technical issues

The purpose of the present invention is to address the shortcomings of the existing technology and provide a heat engine/heat pump that realizes the Carnot cycle, simplifies the structure, improves the heat-to-work conversion efficiency and practicality, and is aimed at industrial, energy, transportation, refrigeration/heating, education, entertainment and other uses.

Technical Solutions

In order to solve the above technical problems, the present invention provides the following technical solutions:

A cylinder comprising at least one piston, wherein the piston has at least one of the following characteristics:

1) The piston includes a drag reduction component, which includes a wheel, a ball, a suspension rope, or a connecting rod, and the suspension rope or connecting rod is not connected to any mechanism outside the cylinder;

2) The piston is liquid;

3) The piston includes an airtight component and a mechanical energy component;

4) The square of the height of the piston shall not be less than 25 times the average effective pressure area of its two bases;

5) The volume of the piston is greater than the product of its length and the average effective air pressure area of its two bases, and the projection of the piston on a plane perpendicular to its direction of movement is greater than the average effective air pressure area of its two bases;

6) The piston is a free piston, which is ferromagnetic and is subject to magnetic force during operation;

7) The piston is an airtight membrane piston.

In order to realize the Carnot heat engine, simplify the structure, and improve the heat-to-work conversion efficiency and practicality, the present invention also provides the following technical solutions:

A cylinder, the outer wall of which is an integrated fully enclosed structure, is used to prevent the working medium gas in the cylinder from leaking out of the cylinder.

Furthermore, it also includes:

At least a portion of the cylinder is switchable between a thermally insulating state and a thermally conductive state. When the at least a portion is in the thermally insulating state, the working fluid gas in contact with the at least a portion of the cylinder is also in the thermally insulating state. When the at least a portion is in the thermally conductive state, the working fluid gas in contact with the at least a portion of the cylinder can exchange heat with an external heat source.

In order to realize the Carnot heat engine, simplify the structure, and improve the heat-to-work conversion efficiency and practicality, the present invention also provides the following technical solutions:

A cylinder comprising at least two spatial regions within the cylinder. During operation of the cylinder, the at least two spatial regions are connected during at least one period and isolated during at least another period. The cylinder operates cyclically, and in each cycle of the cylinder operation, the at least two spatial regions are connected during at least one period and isolated during at least another period. The at least two spatial regions each form a cavity when isolated, and together form a cavity when connected.

Furthermore, it also includes:

The cylinder includes a constant temperature chamber and a variable temperature chamber. A channel and an isobaric device are provided between the variable temperature chamber and the constant temperature chamber. The channel includes a valve that controls whether the variable temperature chamber and the constant temperature chamber are connected. The isobaric device can equalize the pressures of the constant temperature chamber and the variable temperature chamber. If the cylinder includes multiple constant temperature chambers and the temperatures of these constant temperature chambers are different, the variable temperature chamber can be connected to at most one of the constant temperature chambers at any one time. The constant temperature chamber and the variable temperature chamber are each one of the at least two spatial regions.

Furthermore, it also includes:

The cylinder is an annular tube with at least two valves within it. These valves can be opened and closed automatically or under control. When closed, the working gas in the cylinder cannot pass through the valves. When all valves are open, the working gas in the cylinder can circulate, i.e., the working gas can return to its original position after completing a full cycle in the annular tube. The valves are thermally insulated.

Furthermore, it also includes:

The cylinder is annular and has a heat-resistance channel therein. The working fluid gas in the cylinder can pass through the heat-resistance channel, but cannot conduct heat against the direction of airflow through the heat-resistance channel.

Furthermore, it also includes:

The cylinder includes a combustion chamber, and the combustion chamber includes an interlayer. The space in the interlayer is communicated with the space in the cylinder to fully utilize the heat of the heat source and avoid loss.

Furthermore, it also includes:

The cylinder is inelastic, has a fixed shape and a fixed volume, and cannot be expanded or contracted. During the operation of the cylinder, the total volume of all working gases in the cylinder is a fixed value.

Furthermore, it also includes:

The cylinder is capable of movement and can perform external work through this movement. The heat engine outputs mechanical energy by performing external work through the movement of the cylinder. The movement of the cylinder includes one-dimensional, two-dimensional, and three-dimensional motion, specifically reciprocating and rotational motion. The motion is periodic, with each period being an integer multiple of the working cycle of the working fluid gas within the cylinder.

In order to realize the Carnot heat engine, simplify the structure, and improve the heat-to-work conversion efficiency and practicality, the present invention also provides the following technical solutions:

A heat engine comprises a cylinder, wherein the cylinder is any one of the above-mentioned cylinders, or has the characteristics of multiple types of the above-mentioned cylinders.

In order to realize the Carnot heat engine, simplify the structure, and improve the heat-to-work conversion efficiency and practicality, the present invention also provides the following technical solutions:

A heat engine comprises a cylinder, wherein the cylinder comprises a working gas, and a working cycle of the working gas comprises a Carnot cycle.

In order to realize the Carnot heat engine, simplify the structure, and improve the heat-to-work conversion efficiency and practicality, the present invention also provides the following technical solutions:

A heat engine includes an adiabatic engine. The adiabatic engine includes a cylinder containing a working gas. When the cylinder is not in contact with a high-temperature heat source or a low-temperature heat source, the working gas is in an adiabatic state, and its state changes include adiabatic expansion and adiabatic compression. When the cylinder contacts a high-temperature heat source, part of the adiabatic expansion process becomes an isothermal expansion process, and when the cylinder contacts a low-temperature heat source, part of the adiabatic compression process becomes an isothermal compression process. The state changes of the working gas include isothermal expansion, adiabatic expansion, isothermal compression, and adiabatic compression, and the adiabatic engine becomes a Carnot heat engine.

Adiabatic engine is another working mode of heat engine. Adiabatic engine includes a cylinder and a working fluid gas in the cylinder. When the heat engine is not in contact with a heat source, there is no heat input and no power output during operation. The working fluid gas operates in an adiabatic state, and its state change modes include adiabatic expansion and adiabatic compression. At this time, the heat engine is an adiabatic engine. When the adiabatic engine contacts a high/low temperature heat source, inputs heat, and outputs power, the adiabatic engine becomes a heat engine. In the switch from adiabatic engine mode to heat engine mode, if part of the original adiabatic expansion process becomes an isothermal expansion process, and part of the original adiabatic compression process becomes an isothermal compression process, the state change modes of the working fluid gas in the heat engine mode include isothermal expansion, adiabatic expansion, isothermal compression and adiabatic compression. Then this heat engine is a Carnot heat engine.

For the various heat engines proposed above, further, it also includes:

The heat engine includes an energy storage device for storing potential energy. During the operating cycle of the heat engine, the potential energy of the energy storage device is first increased by absorbing heat from a high-temperature heat source and/or releasing heat to a low-temperature heat source, and then released to perform external work. During each operating cycle of the heat engine, the maximum potential energy stored in the energy storage device is no less than half of the external work performed by the heat engine. The potential energy includes gravitational potential energy, electric potential energy, magnetic potential energy, and other potential energy.

Furthermore, it also includes:

The cylinder includes a piston, and the movement of the piston changes the overall center of mass of the cylinder and the piston, causing the cylinder to move, and the movement of the cylinder performs work externally.

Furthermore, it also includes:

The cylinder periodically changes its contact relationship with the high/low temperature heat source. This periodic change includes: 1. Periodic movement of the cylinder relative to the high/low temperature heat source; 2. Periodic changes in the temperature or range of the high/low temperature heat source; and 3. Periodic changes in the connection/disconnection relationship between the temperature-variable chamber and the hot or cold chamber in the cylinder.

In order to realize the Carnot heat engine, simplify the structure, and improve the heat-to-work conversion efficiency and practicality, the present invention also provides the following technical solutions:

A heat engine comprises a cylinder, which is an annular tube-shaped cylinder. At least one piston is arranged in the cylinder, and the piston in the cylinder can return to an initial position after moving one circle.

In order to realize the Carnot heat engine, simplify the structure, and improve the heat-to-work conversion efficiency and practicality, the present invention also provides the following technical solutions:

A heat pump having the same structure as any of the aforementioned heat engines and operating in the reverse process of any of the aforementioned heat engines. The aforementioned heat engines are all Carnot heat engines, and their operation is reversible: in the forward direction, they operate as a heat engine, and in the reverse direction, they operate as a heat pump.

Furthermore, it also includes:

The heat pump includes an energy storage device for storing potential energy. During the heat pump's operating cycle, the potential energy of the energy storage device is first increased by receiving external work, and then released by absorbing heat from a low-temperature heat source and/or releasing heat to a high-temperature heat source. During each operating cycle of the heat pump, the maximum potential energy stored in the energy storage device is no less than half the external work received by the heat pump. This potential energy includes gravitational potential energy, electric potential energy, magnetic potential energy, and other potential energy.

Furthermore, it also includes:

The heat pump includes a cylinder that is movable. The heat pump receives external work through the movement of the cylinder. The cylinder's motion includes one-dimensional, two-dimensional, and three-dimensional motion, specifically reciprocating and rotational motion. The motion is periodic, with each period being an integer multiple of a working cycle of the working fluid gas within the cylinder.

In order to realize the Carnot heat engine, simplify the structure, and improve the heat-to-work conversion efficiency and practicality, the present invention also provides the following technical solutions:

A method for converting internal energy into mechanical energy using a cylinder, comprising a forward or reverse cycle of the following four steps: 1. isothermal expansion of the working gas in the cylinder; 2. adiabatic expansion of the working gas in the cylinder; 3. isothermal compression of the working gas in the cylinder; 4. adiabatic compression of the working gas in the cylinder. The cylinder is any of the above-mentioned heat engines or heat pumps. When operating in the forward cycle, the method is a heat engine method; when operating in the reverse cycle, the method is a heat pump method.

In order to realize the Carnot heat engine, simplify the structure, and improve the heat-to-work conversion efficiency and practicality, the present invention also provides the following technical solutions:

An internal combustion engine comprises a cylinder, wherein the cylinder comprises a piston. When the piston reaches a dead point, the cylinder is divided into at least two areas. When a mixture in any one of the areas is ignited, the mixture in the other areas cannot be immediately ignited.

In order to realize the Carnot heat engine, simplify the structure, and improve the heat-to-work conversion efficiency and practicality, the present invention also provides the following technical solutions:

An internal combustion engine includes a cylinder. The engine operates by burning fuel within the cylinder to produce work. The combustion comprises a reversible chemical reaction. The chemical equilibrium of the reversible chemical reaction is affected by temperature; a decrease in temperature shifts the chemical equilibrium in a positive direction.

Beneficial effects

The beneficial effect of this invention is that, through the creative design of the mechanical relationship between the cylinder and the piston, the heat engine/heat pump workflow truly implements the Carnot cycle, filling a 200-year gap in scientific and technological history. The Carnot heat engine/heat pump reaches the theoretical efficiency limit, solves the leakage problem of existing Stirling heat engines/heat pumps, simplifies the structure of Stirling heat engines/heat pumps and Ericsson heat engines, and improves combustion and heat transfer efficiency. This technology provides the entire industry with new technologies that can improve the efficiency of heat engines and heat pumps, simplify their structure, save energy, reduce exhaust emissions, mitigate environmental pollution, mitigate climate change, and make global economic development more efficient and sustainable.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions in the invention content of this application, the following is a brief introduction to the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present application. Ordinary technicians in this field can also obtain other drawings based on these drawings without paying any creative work.

Figure 1 shows the reciprocating Carnot heat engine used in this application.

Figure 2 shows the rotary Carnot heat engine used in this application.

FIG3 is the running trajectory of the piston center of the rotary Carnot heat engine in this application when there is no heat source.

Figure 4 shows the trajectory of the piston center of the rotary Carnot heat engine in this application after adding a heat source.

Figure 5 shows the multi-cavity rotary Carnot heat engine in this application.

Figure 6 shows the annular Carnot heat engine in this application.

Figure 7 shows the airflow Carnot heat engine in this application.

Figure 8 shows the rotating ring-tube Carnot heat engine in this application.

FIG9 shows the combustion chamber of the cylinder in this application.

Figure 10 is a temporary cavity internal combustion engine in this application.

FIG11 is a piston including a thick portion and a thin portion in this application.

Figure 12 shows the ferromagnetic piston in this application.

Figure 13 shows a multi-cylinder cascade rotary Carnot heat engine in this application.

FIG14 is a Carnot heat engine in this application including a cold chamber, a hot chamber and a variable temperature chamber.

Figure 15 is a piston including a wheel or ball in the present application.

Figure 16 is a piston including a suspension rope in this application.

Figure 17 shows the piston including the connecting rod in this application.

FIG18 is a piston including an airtight membrane in the present application.

FIG19 is a Carnot heat engine in which the piston gas-tight component and the counterweight component are independent in this application.

Figure 20 shows a rotary Carnot heat engine with the heat source in any direction in this application.

Figure 21 is a planar pendulum Carnot heat engine in this application.

Figure 22 is a conical pendulum Carnot heat engine in this application.

FIG23 is a flow chart of the method for realizing the mutual conversion between internal energy and mechanical energy in the present application.

FIG24 is an internal combustion engine including a reversible chemical reaction in the present application.

Modes for Carrying Out the Invention

In order to make the purpose, technical solutions and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in this application. Obviously, the described embodiments are part of the embodiments of this application, rather than all the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

This application uses theoretical thermodynamic processes to describe the working cycle of a heat engine/heat pump. Those skilled in the art will understand that due to suboptimal materials and processing technology, there are slight differences between the actual operating process of a heat engine and the theoretical model. In this application, mapping an actual operating process of a heat engine to a theoretical process means ignoring the above differences. For those skilled in the art, this ignoring is normal, and this mapping relationship is objective and definite. Unless otherwise specified, all thermodynamic processes mentioned in this application are analyzed as quasi-static processes.

According to the ideal gas state equation PV=nRT, R is a constant, and n is a constant for a closed gas, so PV/T is a constant.

During an isothermal process, temperature T is constant, and therefore PV is also constant. During isothermal compression, volume V decreases while pressure P increases. The external environment performs work on the working gas, increasing its internal energy and requiring it to release heat to maintain a constant temperature. During isothermal expansion, V increases while P decreases. The working gas performs work on the external environment, decreasing its internal energy and requiring it to absorb heat to maintain a constant temperature.

During the adiabatic compression process, the outside world does work on the working gas, the internal energy of the working gas increases and it cannot release heat, so T increases, while V decreases, and P must also increase.

During the adiabatic expansion process, the working fluid gas does work on the outside world, its internal energy decreases and it cannot absorb heat, so T decreases, while V increases, then P must also decrease.

The piston is a common component in the cylinder, and its functions include: 1. Isolating the gas on both sides of the piston; 2. Isolating the heat on both sides of the piston; 3. Connecting the machinery to transmit the pressure of the gas to the outside world or to transmit the external force to the gas; 4. Applying force to the gas with its own mechanical energy or converting the pressure of the gas into its own mechanical energy. Corresponding to the above four functions, a piston can be abstracted into four components: an airtight component, an insulating component, a hardened component, and a mechanical energy component. Among them, the airtight component is necessary, and the other three are optional. When the piston applies force to the gas through gravity or kinetic energy, the mechanical energy component is also called a counterweight component. In this application, the above four components are an abstraction of the function of the piston, and do not necessarily mean that the piston can be disassembled into multiple parts. For example, the piston of an ordinary gasoline engine includes an airtight component, a hardened component, and an insulating component.

The present invention provides a heat engine, comprising a cylinder, wherein the cylinder comprises a working fluid gas, and the working cycle of the working fluid gas comprises a Carnot cycle.

In various embodiments of the present invention, the cylinder or a portion of the cylinder may be in an adiabatic state, not exchanging heat with the outside world, or in a heat-conducting state, capable of exchanging heat with the outside world. The cylinder or a portion of the cylinder can switch between the adiabatic and heat-conducting states. Contact with a high/low temperature heat source means switching to a heat-conducting state, capable of exchanging heat with the heat source, while separation from or away from the high/low temperature heat source means switching to an adiabatic state, not exchanging heat with the outside world.

The cylinder can be made of various solid materials such as metal, ceramic, glass, bamboo, stone, plastic, rubber, fiber, crystal, fabric, biomass, paper, polymer material, etc., and can also be made of two or more materials.

The cylinder is inelastic, has a fixed shape and a fixed volume, and cannot be stretched or expanded.

The cylinder contains a working gas. During operation of the heat engine/heat pump, the cylinder remains sealed, and the working gas therein is not in communication with the outside world. The working gas may be hydrogen, helium, nitrogen, argon, krypton, xenon, sulfur hexafluoride, or another gas or a mixture of multiple gases, such as air.

The outer wall of the cylinder is a fully enclosed, one-piece structure. That is, the entire outer wall of the cylinder is made of a single, airtight solid material, completely enclosed, rather than being a combination of multiple pieces of solid material that can move relative to each other. The outer wall of the entire cylinder contains no holes or gaps that could communicate with the working gas within the cylinder. In particular, the inside and outside of the cylinder are not separated by a piston. Therefore, the working gas within the cylinder is unlikely to leak out, and the lubricant within the cylinder is also unlikely to be lost. Therefore, the heat engine can operate for long periods of time without requiring replenishment of the working gas and lubricant.

Example 1: Reciprocating Carnot Heat Engine

There is at least one piston in the cylinder. The piston can move in the cylinder and is thermally insulated.

As shown in Figure 1, the cylinder is placed horizontally on a smooth horizontal surface, with its central axis oriented horizontally and parallel to the horizontal plane. A piston is located within the cylinder, which can move left and right along the central axis. The piston divides the cylinder's interior into two chambers, each containing an equal amount of working fluid. The piston is thermally insulated, preventing heat from being transferred from one chamber to the other.

Each end of the cylinder has a protrusion perpendicular to the central axis, and the top end of the protrusion is heat-conducting and serves as a heat-conducting end. When the heat-conducting end contacts a high/low temperature heat source, the heat source can exchange heat with the working fluid gas in the cavity on the same side of the cylinder. Except for the heat-conducting end, the rest of the cylinder is heat-insulated. Heat cannot be conducted from the working fluid gas in one cavity to the working fluid gas in another cavity through the cylinder. When one heat-conducting end contacts neither a high-temperature heat source nor a low-temperature heat source, the working fluid gas in the cavity on the same side of the cylinder is in a heat-insulating state.

The heat conduction and insulation state of the heat conduction end can be dynamically adjusted by providing a movable insulation layer on the heat conduction end, or adding an insulation cover in the area of the heat conduction end's running track that does not contact the high/low temperature heat source.

That is, at least a portion of the cylinder is switchable between an adiabatic state and a heat-conducting state. When the at least a portion is in the adiabatic state, the working fluid gas in contact with the at least a portion within the cylinder is also in the adiabatic state. When the at least a portion is in the heat-conducting state, the working fluid gas in contact with the at least a portion within the cylinder can exchange heat with an external heat source.

In addition to the heat-conducting end, there are other methods for switching the heat-conducting and heat-insulating states of the cylinder, such as the hot chamber-cold chamber-variable temperature chamber structure in the twelfth embodiment.

If the cylinder is stationary on a smooth surface and the piston is also stationary relative to the cylinder, the pressure of the working gas in the two chambers will be equal. If the temperature of the working gas in the two chambers is also equal, the volume of the working gas in the two chambers will also be equal, and the position of the piston in the cylinder will be the equilibrium position. No high-temperature heat source or low-temperature heat source is provided. This is the initial state.

Those skilled in the art will appreciate that in the following analysis, the working fluid in the cylinder is assumed to be an ideal gas, and the frictional resistance of the piston and the resistance of the cylinder moving on the smooth surface are neglected. In the following analysis of this embodiment, the description of the cylinder's movement does not include the piston.

A horizontal impulse I is applied to the cylinder, causing it to move rightward. The resultant force on the piston is 0, and it does not move with the cylinder. That is, it moves leftward relative to the cylinder, compressing the working gas in the left chamber. As the working gas pressure in the left chamber increases while the pressure in the right chamber decreases, the piston begins to experience a rightward force and accelerates rightward. Its speed relative to the cylinder's leftward motion gradually decreases, reaching zero before it begins to move rightward relative to the cylinder, gradually accelerating. After passing the equilibrium position, inertia continues to move rightward relative to the cylinder, compressing the working gas in the right chamber. The combined pressure from both sides shifts the piston's motion to the left, causing it to gradually decelerate to zero relative to the cylinder. After that, its direction of motion relative to the cylinder returns to the left, gradually accelerating. In other words, with the cylinder as a reference, the piston oscillates left and right.

During this process, the cylinder continues to slide to the right. When the piston reaches its rightmost position relative to the cylinder, it is given another horizontal impulse to the left, -I, causing the combined center of mass of the cylinder and piston to return to rest. Because the piston is not in equilibrium and cannot come to rest, neither can the cylinder. Both the piston and cylinder vibrate left and right about the combined center of mass, their motion directions and momentum always opposite, and their amplitudes inversely proportional to their masses. This is a vibrating state.

Assume the mass of the cylinder is m0, its velocity relative to the center of mass is v0, and its displacement is s0; the mass of the piston is m1, its velocity relative to the center of mass is v1, and its displacement is s1. Then:

m0v0 = -m1v1

m0s0 = -m1s1

When s0 = s1 = 0, the piston passes through the equilibrium position, the velocities of the piston and the cylinder reach their maximum, and the overall kinetic energy is at its maximum. The larger the value of m1/m0, the greater the ratio of the cylinder's kinetic energy to the overall kinetic energy.

When v0 = v1 = 0, the piston reaches its extreme left or right position. Conversely, the cylinder reaches its extreme right or left position, both of which are about to change direction. The working gas in one chamber is compressed to its minimum volume, highest pressure, and highest temperature. The kinetic energy of the system is zero, and the previous kinetic energy is completely converted into the internal energy of the compressed working gas. The working gas in each chamber undergoes two processes during each vibration cycle: adiabatic compression and adiabatic expansion. The processes experienced by the working gas in the two chambers are always opposite.

It is easy to understand that the above method of applying two impulses in opposite directions is only one of the many methods for causing the cylinder to enter the vibration state from the initial state. There are other methods, such as heating the two chambers alternately, which can also cause the cylinder to enter the vibration state.

The present invention provides a heat engine, characterized in that it includes an adiabatic machine. The adiabatic machine includes a cylinder, and the cylinder includes a working fluid gas. When the adiabatic machine is not in contact with a high-temperature heat source and a low-temperature heat source, the working fluid gas is in an adiabatic state, and its state change mode includes adiabatic expansion and adiabatic compression, and the adiabatic machine cannot continuously perform external work. When the adiabatic machine is in contact with a high-temperature heat source, part of the adiabatic expansion process becomes an isothermal expansion process, and when the adiabatic machine is in contact with a low-temperature heat source, part of the adiabatic compression process becomes an isothermal compression process. The state change mode of the working fluid gas includes isothermal expansion, adiabatic expansion, isothermal compression and adiabatic compression, and it can continuously perform external work. The adiabatic machine becomes a Carnot heat engine.

The cylinder is an adiabatic machine. In a vibrating state, the working medium gas therein is in an adiabatic state, and its state change mode includes adiabatic expansion and adiabatic compression.

The cylinder can move and can do external work through the movement. The heat engine outputs mechanical energy by doing external work through the movement of the cylinder. The movement of the cylinder includes one-dimensional movement, two-dimensional movement and three-dimensional movement, specifically, reciprocating movement and rotational movement. The cylinder in this embodiment is one-dimensional and also reciprocating. The cylinders in Examples 2 and 8 are two-dimensional and also rotational. The cylinder of the plane pendulum Carnot heat engine in Example 4 is two-dimensional and also reciprocating; the cylinder of the conical pendulum Carnot heat engine is three-dimensional and also rotational.

The cylinder in the vibrating state can perform work externally. However, due to the lack of energy input, the work cannot be sustained for a long time and will stop once the energy of the vibration is consumed.

The cylinder can move relative to the high-temperature heat source or the low-temperature heat source.

Next, we'll discuss high-temperature and low-temperature heat sources. High-temperature heat sources include those that generate heat by burning any solid, liquid, or gaseous fuel, as well as heat from other energy sources such as chemical reactions, nuclear energy, solar energy, electricity, light energy, wind energy, hydropower, biomass energy, geothermal energy, compressed gas, and waste heat. Low-temperature heat sources include those that dissipate heat into any low-temperature solid, liquid, or gas, such as air, water, or liquid nitrogen, or dissipate heat via radiation to other low-temperature objects or areas.

During vibration, the heat conductive ends at both ends of the cylinder each have a reachable range. A high-temperature heat source and a low-temperature heat source are fixed on the smooth plane, and a high-temperature heat source is placed at the inner end of the reachable range of the two heat conductive ends, and a low-temperature heat source is placed at the outer end of the reachable range of the two heat conductive ends. The inner end refers to the end of the reachable range of the heat conductive end close to the overall center of mass, and the outer end refers to the end of the reachable range of the heat conductive end away from the overall center of mass. That is, for the heat conductive end on the left, the high-temperature heat source and the low-temperature heat source are placed at the right and left ends of the reachable range respectively; for the heat conductive end on the right, the high-temperature heat source and the low-temperature heat source are placed at the left and right ends of the reachable range respectively.

When the cylinder moves to the rightmost position and the piston moves to the leftmost position, the working fluid gas in the left cavity is compressed to the minimum volume and the temperature and pressure reach the maximum, the left heat-conducting end contacts the high-temperature heat source, and the temperature of the high-temperature heat source is equal to the temperature of the working fluid gas in the left cavity; at the same time, the right heat-conducting end contacts the low-temperature heat source, and the working fluid gas in the right cavity expands to the maximum volume and the temperature and pressure reach the minimum, and the temperature of the low-temperature heat source is equal to the temperature of the working fluid gas in the right cavity.

At this time, the state of the working fluid gas in the cavity on the left is that the adiabatic compression process has ended, and the left end of the cylinder and the piston begin to move away. The working fluid gas in the cavity on the left absorbs heat from the high-temperature heat source to maintain the temperature, which is an isothermal expansion process. Compared with the adiabatic expansion process, the temperature and pressure of the working fluid gas in the cavity on the left are higher when the isothermal expansion reaches the same volume. At the same time, the state of the working fluid gas in the cavity on the right is that the adiabatic expansion process has ended, and the right end of the cylinder and the piston begin to approach. The working fluid gas in the cavity on the right is able to release heat to the low-temperature heat source to maintain the temperature, which is an isothermal compression process. Compared with the adiabatic compression process, the temperature and pressure of the working fluid gas in the cavity on the right are lower when it is isothermally compressed to the same volume.

During the isothermal process described above, compared to the absence of a heat source, at each position, the pressure on the left side of the piston is greater, while the pressure on the right side is less. The piston is subjected to a greater combined rightward pressure, thereby gaining more kinetic energy. Correspondingly, at each position, compared to the absence of a heat source, the leftward pressure on the left chamber of the cylinder is greater, while the rightward pressure on the right chamber is less. The overall combined leftward pressure is greater, thereby gaining more kinetic energy.

Until the cylinder moves to the left, causing the left heat-conducting end to leave the high-temperature heat source and the right heat-conducting end to leave the low-temperature heat source, the isothermal process ends, the working fluid gas in the left cavity enters the adiabatic expansion process, and the working fluid gas in the right cavity enters the adiabatic compression process.

The kinetic energy increased during the isothermal process will increase the amplitude of the cylinder and the piston. When the cylinder is made to do work externally and the increased kinetic energy is transferred out, the cylinder and the piston can maintain their original amplitude. When the cylinder moves to the leftmost position and the piston moves to the rightmost position, so that the cavity on the right is compressed to the minimum, the heat-conducting end on the right contacts the high-temperature heat source, and the working fluid gas in the right cavity enters the isothermal expansion process. At the same time, the heat-conducting end on the left can contact the low-temperature heat source, and the working fluid gas in the left cavity enters the isothermal compression process. Until the cylinder moves to the right, so that the heat-conducting end on the right leaves the high-temperature heat source and the heat-conducting end on the left leaves the low-temperature heat source, the isothermal process ends, the working fluid gas in the cavity on the right enters the adiabatic expansion process, and the working fluid gas in the cavity on the left enters the adiabatic compression process.

The above describes the working process of the cylinder within one working cycle. The cylinder can continuously cycle according to this process to continuously perform external work.

Figure 1 shows the cylinder in the leftmost position and the rightmost position respectively.

As can be seen from the above description, within each working cycle, the working gas in the two chambers undergoes four processes: isothermal expansion, adiabatic expansion, isothermal compression, and adiabatic compression. The working cycle of the working gas is a Carnot cycle. Therefore, the cylinder operates in this mode as a Carnot heat engine.

It can be summarized as follows: the overall center of mass of the cylinder and the piston is changed by the movement of the piston, so that the cylinder moves, and work is performed externally by the movement of the cylinder.

From the perspective of the original adiabatic engine's operating cycle, intermittent contact with a heat source transforms a portion of the adiabatic expansion of the working gas within the engine into isothermal expansion, and a portion of the adiabatic compression of the working gas within the engine into isothermal compression, thereby transforming the original adiabatic engine into a heat engine. A Carnot heat engine is implemented by intermittently contacting each chamber of its cylinder with high and low-temperature heat sources. Specifically, during the adiabatic expansion of the working gas within the engine, the temperature is reduced. Contact with a high-temperature heat source replenishes heat to the working gas, preventing the temperature drop. This portion of the original adiabatic expansion process is converted to isothermal expansion. Similarly, during the adiabatic compression of the working gas within the engine, the temperature is increased. Contact with a low-temperature heat source absorbs heat from the working gas, preventing the temperature rise. This portion of the original adiabatic compression process is converted to isothermal compression.

The Carnot heat engines in Examples 2, 4, 6, 8 and 12 of the present application are also realized by an adiabatic engine by allowing each cavity of its cylinder to intermittently contact a high/low temperature heat source.

When the high-temperature heat source and the low-temperature heat source are fixed in position and their range of action is not zero, the previous process of the working gas in the chamber has not yet concluded when the heat conductive end contacts the high/low-temperature heat source. If the previous process ends at t0, the contact time between the heat conductive end and the high/low-temperature heat source is from t0-t1 to t0+t2. However, since heat transfer between the high/low-temperature heat source and the working gas in the chamber passes through the cylinder wall of the heat conductive end, there is a hysteresis effect. Therefore, the absorption and release of heat by the working gas in the chamber can be delayed until after t0. Furthermore, if the high-temperature heat source is a hot gas (flame), the airflow driven by the heat conductive end approaching will push the hot gas away, while the airflow driven by the heat conductive end moving away will attract the hot gas, similarly delaying the period during which the working gas acquires heat. The contact method between the cylinder and the heat source of the planar pendulum Carnot heat engine in Example 4 is the same as that of this embodiment.

As a product for actual use, there is no ideal smooth surface. The cylinder can use wheels, suspensions, connecting rods, magnetic levitation, lubricants and other methods to reduce the frictional resistance of reciprocating motion. The use of hydrogen or helium as the working gas can improve the heat transfer efficiency. Since both sides of the piston are within the cylinder, the airtightness requirements for the piston are not high, and a small amount of working gas leaking from one cavity to the other does not affect the operation of the heat engine. This is also beneficial to reducing the frictional resistance of the piston. A limiter can be added to the cylinder to limit the range of movement of the piston. If the amount of working gas in the cavity on one side is larger due to leakage of working gas, the piston will be stopped by the limiter when moving to the other side, making it easier for the working gas to leak back and automatically balancing the amount of working gas in the two cavities.

Example 2: Rotary Carnot Heat Engine

Connecting a crankshaft to the cylinder of the reciprocating Carnot heat engine described in Example 1 can achieve rotary external work. However, this structure is too complex and inefficient. Simpler and more efficient implementations are possible.

As shown in Figure 2, a rotary Carnot heat engine also includes a cylinder. The cylinder contains a working fluid gas. During operation of the heat engine, the cylinder remains sealed, and the working fluid gas therein is not accessible to the outside world. The outer wall of the cylinder is a one-piece, fully enclosed structure. The cylinder contains at least one piston, which is capable of moving within the cylinder. When there is only one piston in the cylinder, the piston divides the cylinder into two chambers, with equal amounts of working fluid gas in each chamber. The piston is thermally insulated.

Furthermore, the cylinder is symmetrical about its geometric center O and does not include any protrusions perpendicular to its central axis. The piston is also symmetrical about its geometric center. When the cylinder is placed horizontally, the equilibrium position of the piston within the cylinder and the combined center of mass of the cylinder and piston are both at point O. A shaft is mounted at point O, allowing the cylinder to rotate about point O in a vertical plane.

Each end of the cylinder has a heat-conducting end. The heat-conducting end is capable of conducting heat when in contact with a high-temperature heat source or a low-temperature heat source. Heat cannot be transferred from the working gas in one chamber to the working gas in the other chamber through the cylinder or the piston. When the heat-conducting end is not in contact with either a high-temperature heat source or a low-temperature heat source, the working gas in both chambers of the cylinder is in a thermally adiabatic state.

Establish an x-y rectangular coordinate system with O as the origin, with x as the horizontal axis and y as the vertical axis. Initially, there are no high-temperature or low-temperature heat sources. The cylinder's central axis lies on the x-axis. Its right end is designated as end A, and its left end as end B. The piston is stationary at point O. The cavity between the piston and end A is designated as cavity A, and the cavity between the piston and end B is designated as cavity B.

The cylinder slowly rotates counterclockwise from its initial state, with end A pointing upward and end B pointing downward, through an angle θ. Those skilled in the art will appreciate that slow rotation means rotation slow enough to negligibly affect the inertia and centrifugal force of the piston along the cylinder's central axis, and to allow sufficient time for the working fluid in the chamber to achieve uniform heat distribution as its temperature changes. This slow rotation can be achieved by connecting a flywheel to the cylinder.

It is easy to understand that the flywheel is an abstraction of the cylinder's rotational inertia and is not necessarily an independent component. As long as the cylinder's rotational inertia is large enough, it can replace the independent flywheel component.

When θ is between 0° and 90°, the piston moves toward end B under the force of gravity, entering the third quadrant. Gravity exerts a counterclockwise torque on the flywheel, generating work on the flywheel. The gas in chamber A expands adiabatically, which, combined with the force of gravity on the piston, produces work on the gas in chamber B, causing it to adiabatically compress.

During slow rotation, the pressure relationship in the two chambers is:

Pa+Gsinθ/S=Pb

Where Pa and Pb are the pressures of the working fluid gas in chambers A and B respectively, G is the weight of the piston, and S is the cross-sectional area of the piston.

When θ is 90°, the piston reaches the negative half of the y-axis, closest to end B. When θ is between 90° and 180°, the piston begins to move toward end A, entering the fourth quadrant. Gravity exerts a clockwise torque, causing the gas in chamber B to expand adiabatically. This, along with the flywheel, works on the piston and the gas in chamber A, causing the piston to rise and the gas in chamber A to compress adiabatically. When θ is 180°, the piston returns to point O.

The process of θ changing from 180° to 360° is similar to the process from 0° to 180°, except that the positions of terminals A and B are swapped. When θ changes from 180° to 270°, chamber A undergoes adiabatic compression, while chamber B undergoes adiabatic expansion. When θ changes from 270° to 360°, chamber A undergoes adiabatic expansion, while chamber B undergoes adiabatic compression. It can be seen that the piston rotates twice for every one rotation of the cylinder. As shown in Figure 3, the motion trajectory of the piston's center is a closed curve, tangent to the x-axis only at the origin. At all other locations, it lies below the x-axis and is bilaterally symmetric about the y-axis.

For two angles θ1 and θ2, if θ1 and θ2 are symmetric about the y-axis, that is, θ1 + θ2 = n * 360° + 180° (n is an integer), then for chamber A or chamber B, the volume, pressure, and temperature of the working gas at positions θ1 and θ2 are equal. This can be deduced from the constant PV/T and the equation Pa + Gsinθ/S = Pb.

When θ moves from 0° to 90° and from 180° to 270°, the piston moves from the origin to the negative half of the y-axis, reducing its gravitational potential energy. Work W1 is performed on the flywheel, and work W2 is performed on the working fluid in the chamber below. When θ moves from 90° to 180° and from 270° to 360°, the piston moves from the negative half of the y-axis to the origin. Its gravitational potential energy increases, receiving work W1 from the flywheel and work W2 from the working fluid in the chamber below. The total work performed by the piston per rotation is 0.

When the cylinder rotates to a vertical position (θ is 90° or 270°), the working gas in the upper chamber reaches its maximum volume, with minimum temperature and pressure, at T2; the working gas in the lower chamber reaches its minimum volume, with maximum temperature and pressure, at T1. T1 > T2. The half-turn of the lower chamber to the upper chamber is an adiabatic expansion process, with the temperature continuously decreasing from T1 to T2. When the chamber passes through the positive x-axis, the temperature of the working gas therein is T0, with T1 > T0 > T2. At this time, the other chamber is on the negative x-axis, and the working gas temperature therein is also T0. During the adiabatic process, the internal energy of the working gas in both chambers can only be changed by the movement of the piston.

A high-temperature heat source at T3 is set in the fourth quadrant, so that end A or B, when passing through it, contacts the high-temperature heat source and absorbs heat. A low-temperature heat source at T4 is set in the second quadrant, so that end A or B, when passing through it, contacts the low-temperature heat source and releases heat. End A or B is in adiabatic mode when it is not in contact with the high or low-temperature heat source. T3 > T4.

When θ is 0°, end A has just left the high-temperature heat source, and the temperature of the working gas in chamber A is T3. End B has just left the low-temperature heat source, and the temperature of the working gas in chamber B is T4. At this time, sinθ is 0, and Pa = Pb. Since T3 > T4 and the amount of working gas in chambers A and B is equal, the volume of the working gas in chamber A is greater than that in chamber B. Therefore, the piston is located to the left of point O, that is, closer to end B.

When θ changes from 0° to 90°, the working gas in chamber A undergoes an adiabatic expansion process, and the temperature gradually decreases; the working gas in chamber B undergoes an adiabatic compression process, and the temperature gradually increases.

When θ reaches 90°, the piston reaches its closest position to end B. The temperature of the working gas in chamber A drops to T4 and contacts the low-temperature heat source, ending the adiabatic expansion process. It then enters an isothermal compression process, maintaining the temperature at T4. The temperature of the working gas in chamber B rises to T3 and contacts the high-temperature heat source. The adiabatic compression process ends, and it then enters an isothermal expansion process, maintaining the temperature at T3.

The heat engine includes an energy storage device for storing potential energy. In the working cycle of the heat engine, the potential energy of the energy storage device is first increased by absorbing heat from a high-temperature heat source and/or releasing heat to a low-temperature heat source, and then work is performed externally by releasing the potential energy. In each working cycle of the heat engine, the maximum potential energy stored in the energy storage device is not less than half of the work performed externally by the heat engine. The two processes of increasing the potential energy of the energy storage device and performing work externally by releasing the potential energy may partially overlap. The potential energy includes gravitational potential energy, electric potential energy, magnetic potential energy, and other potential energy.

The piston is an energy storage device. Its gravitational potential energy increases as it moves upward, and when it is on the left side of the y-axis, it releases this gravitational potential energy to produce work on the cylinder/flywheel rotation. In this application, the pistons in Examples 4 and 6 and the working fluids in Examples 7 and 8 are also energy storage devices.

As θ moves from 90° to 180°, the piston begins to move toward end A. When θ reaches 180°, the piston is to the left of point O, that is, closer to end A. Therefore, there must be an angle θ0 between 90° and 180° where the piston reaches point O. As θ moves from 90° to θ0, the working gas in chamber B absorbs heat from the high-temperature heat source and, together with the flywheel, performs work on the piston and the working gas in chamber A. This increases the piston's gravitational potential energy and the internal energy of the working gas in chamber A. This newly generated internal energy is released to the low-temperature heat source. As θ moves from θ0 to 180°, the piston moves closer to end A, and the trajectory of its geometric center lies in the second quadrant. The piston releases gravitational potential energy to perform work on the flywheel.

The process from θ 180° to 360° is similar to the process from 0° to 180°, except that the positions of ends A and B are swapped. As θ moves from 180° to 270°, the piston continues to release gravitational potential energy to perform work on the flywheel. The working gas in chamber A undergoes adiabatic compression, while the working gas in chamber B undergoes adiabatic expansion. As θ moves from 270° to 360°, the piston first undergoes isothermal expansion work on the flywheel and the working gas in chamber A, increasing its gravitational potential energy. The piston reaches point O at θ = θ0 + 180°, then releases gravitational potential energy to perform work on the flywheel. The working gas in chamber A undergoes isothermal expansion, while the working gas in chamber B undergoes isothermal compression.

It can be seen that during one counterclockwise rotation of chamber A or B, starting from the negative half of the y-axis, the working fluid within it undergoes isothermal expansion in the fourth quadrant, adiabatic expansion in the first quadrant, isothermal compression in the second quadrant, and adiabatic compression in the third quadrant. Its operating cycle is the Carnot cycle.

When the piston is moving to the left of the y-axis, the work done on the flywheel is the integral of the piston's weighted force, tangential to the cylinder's rotation, over the piston's travel path. When the piston is moving to the right of the y-axis, the negative work done on the flywheel is also the integral of the piston's weighted force, tangential to the cylinder's rotation, over the piston's travel path. Alternatively, the work done on the flywheel by the piston is the integral of the torque generated by the piston's weight over the piston's rotational angle. This torque is negative when the direction is opposite to the flywheel's rotation.

For two angles θ1 and θ2, if θ1 and θ2 are symmetric about the y-axis, and θ1 is to the left of the y-axis, then for chamber A or chamber B, the volume and temperature at position θ1 are smaller than at position θ2. As shown in Figure 4, the motion trajectory of the piston's center is a closed curve, with the portion to the left of the y-axis being longer. At any y-value covered by the trajectory, if the horizontal coordinates of the two points corresponding to the closed curve are x1 and x2, where x1 < x2, then -x1 > x2. That is, of the two intersections of the closed curve and a horizontal line, the left intersection is farther from the y-axis. Therefore, the integral of the piston's weight force, tangential to the cylinder's rotation, over the piston's path has a greater absolute value to the left of the y-axis than to the right of the y-axis, and the net work performed by the piston on the flywheel is positive. In other words, the cylinder can continuously perform external work.

The above describes the process of converting heat from a high-temperature heat source into work through gravitational potential energy. Taking chamber A as an example, when operating in the fourth quadrant, the working fluid in chamber A absorbs heat from the high-temperature heat source, performing work on the piston, increasing its gravitational potential energy. Before entering the first quadrant (when θ is θ0 + 180°), the piston begins releasing this gravitational potential energy to perform work on the flywheel.

In each working cycle, all the work done by the heat engine comes from the gravitational potential energy of the piston.

It can be summarized as follows: the overall center of mass of the cylinder and the piston is changed by the movement of the piston, so that the cylinder moves, and work is performed externally by the movement of the cylinder.

In the simplest case, the heat engine has only two moving parts, a rotating cylinder and a piston that reciprocates in the cylinder. It is the simplest external combustion engine.

Obviously, the above process can also be achieved through other potential energy fields. For example, if the cylinder is rotated horizontally around point O, unaffected by gravity, and an electrostatic field is applied in the opposite direction of the y-axis, causing the piston to have a positive charge, the working fluid in the chamber running in the fourth quadrant absorbs heat from the high-temperature heat source, performing work on the piston, increasing its electric potential energy. Before entering the first quadrant, the piston begins to release this electric potential energy to perform work on the flywheel.

Instead of using an electrostatic field, a static magnetic field in the opposite direction of the y-axis can be added to make the piston magnetic. During the rotation of the cylinder, the magnetic force on the piston is directed opposite to the y-axis. Then, the working fluid gas in the cavity running in the fourth quadrant absorbs heat from the high-temperature heat source, performs work on the piston, increases the magnetic potential energy of the piston, and begins to release the magnetic potential energy of the piston to perform work on the flywheel before entering the first quadrant.

As can be seen from the above discussion, a fully enclosed, integrated cylinder can be fixed at any position along any chordal direction of any circle that is non-perpendicular to the potential energy field. The cylinder contains a free piston, dividing it into at least two chambers. As the cylinder rotates about the center of the circle and one of the pistons reaches a low potential energy point, the working fluid in one chamber begins to exchange heat with a high-temperature heat source, while the working fluid in the other chamber begins to exchange heat with a low-temperature heat source, thus forming a rotary Carnot heat engine.

If there are two pistons in the cylinder, the working gas is divided into three chambers. In addition to chambers A and B, there is also chamber O between the two pistons. When the working gas in chambers A and B is equal, the cylinder operates similarly to a case with only one piston, equivalent to treating the two pistons and the gas in chamber O as a single piston. The same applies to cases with more pistons. Cylinders and heat engines with more than one piston are also within the scope of protection of this application.

Connect two cylinders with two pistons perpendicularly at their respective points O, and open up their O chambers to create a cross-shaped cylinder with four pistons and five chambers. Alternatively, rotate the two cross-shaped cylinders 45° relative to each other at their respective points O, connect them, and open up their O chambers to create a cross-shaped cylinder with eight pistons and nine chambers. Excluding the central O chamber, the other eight chambers are called end chambers. The angle between any two adjacent end chambers is equal, as shown in Figure 5.

Each end chamber is separated from chamber O by a piston and cannot contact other pistons. When the working gas in the eight end chambers is equal in amount, the cylinder operates in the same manner as a straight cylinder with a single piston (Figure 2). When different chambers reach the same position, the temperature, volume, and pressure of the working gas within them are the same. For two angles θ1 and θ2, if θ1 and θ2 are symmetrical about the y-axis, and θ1 is to the left of the y-axis, then the working gas temperature and volume within any end chamber at position θ1 are lower than at position θ2, and the piston it contacts is further away from point O. The total counterclockwise torque generated by gravity on each piston is always greater than the total clockwise torque. Therefore, it can rotate continuously and perform external work.

The ends of the eight end cavities are widened toward both sides along the circumferential direction until they touch the adjacent end cavities, but the adjacent end cavities are thermally insulated from each other. Then, the ends of these end cavities occupy the entire circumference, which can ensure that during continuous rotation, the high-temperature heat source and the low-temperature heat source are always in contact with at least one end cavity, thereby avoiding heat waste.

Similarly, there may be cylinders with more or fewer cavities, all of which are within the scope of protection of this application.

Obviously, during the operation of the heat engine, no matter how many chambers the cylinder is divided into, the sum of the volumes of all the chambers is fixed. That is, the sum of the volumes of all the working gases in the cylinder is a constant value.

To meet the requirements of the Carnot cycle, the working gas temperature at the end of the adiabatic process must be equal to the temperature of the heat source it will contact. If this is not the case, the temperature or range of the heat source can be adjusted. Both the high-temperature and low-temperature heat sources should begin on the y-axis for maximum efficiency, and their end positions can be adjusted to ensure that the temperature of the high-temperature heat source is equal to the temperature at the end of the adiabatic compression state, and the temperature of the low-temperature heat source is equal to the temperature at the end of the adiabatic expansion state. The ranges of the high and low-temperature heat sources in Examples 4, 6, 7, and 8 are also adjustable.

The starting points of the two heat sources can be altered by changing the shape of the cylinder. As shown in Figure 20, only the middle section of the cylinder is straight, and the piston operates within this straight section. The cylinder's ends are bent, and the point where they touch the circumference is offset 45° counterclockwise from where the straight section extends to the circumference. When the piston operating section is vertical and the gas temperature in the lower chamber is highest, the lower end of the cylinder moves from 270° to 315°, marking the starting point of the high-temperature heat source. Similarly, the starting point of the low-temperature heat source moves from 90° to 135°.

Similarly, if both ends of the cylinder are bent 135° clockwise, the starting point of the high-temperature heat source can be adjusted to the 135° position, and the starting point of the low-temperature heat source can be adjusted to the 315° position.

In some embodiments, through multiple sections of selectable tubes or switchable valves, each end of the section where the piston operates can be selectively connected to any one of the multiple heat-conducting ends on the circumference, so that the starting position of the high/low temperature heat source can be dynamically adjusted.

While keeping the cylinder straight, the starting positions of the high-temperature heat source and the low-temperature heat source can also be interchanged. As shown in Figure 19, the piston in the straight cylinder includes an airtight component and a counterweight component. The airtight component and the counterweight component here are two separable solid components that can move relative to each other. The airtight component is used to isolate the working gas on both sides of the piston. The counterweight component passes through the airtight component, and each end is connected to the airtight component by a rope passing around a fixed pulley fixed to the inner wall of the cylinder. It is easy to understand that the movement direction of the counterweight component is always opposite to that of the airtight component.

The mass of the counterweight component is greater than that of the airtight component. Its cross-sectional area is smaller than that of the airtight component. Therefore, when the cylinder rotates from horizontal to vertical, the counterweight component moves downward, driving the airtight component upward. This compresses and heats the working fluid in the upper chamber, while expanding and cooling the working fluid in the lower chamber. This allows the starting point of the high-temperature heat source to be set at the highest point (90°), and the starting point of the low-temperature heat source to be set at the lowest point (270°).

Example 3: Mechanical Energy Piston

As can be seen from the preceding description, the pistons described in Examples 1 and 2 are free pistons, unconnected to the outside world. Their movement cannot directly generate external work through mechanical components. Instead, the movement of the piston changes the center of mass of the cylinder and piston, causing the cylinder to move, and external work is generated through the movement of the cylinder. This type of piston includes a mechanical energy component and is referred to as a mechanical energy piston. Mechanical energy pistons include kinetic energy pistons and potential energy pistons.

Most pistons have kinetic energy and potential energy, but only the pistons that compress the working fluid gas in the cylinder with their own kinetic energy/potential energy during the working process are mechanical energy pistons.

The kinetic energy piston runs in the cylinder and compresses the working medium gas in the cylinder with its own kinetic energy during operation. The mass of the kinetic energy piston is not less than one-fifth of the mass of the cylinder.

In the reciprocating Carnot heat engine of the first embodiment, the ratio of the piston amplitude to the cylinder amplitude is inversely proportional to the masses of the two. If the piston mass is less than one-fifth of the cylinder mass, the cylinder amplitude and kinetic energy are too small, which is not conducive to external work.

Potential energy pistons include pistons that are subject to forces in various potential energy fields and, during operation, can compress the working fluid in the cylinder through the forces exerted by the potential energy fields. These pistons, in particular, include gravity potential energy pistons. Gravity potential energy pistons compress the working fluid in the cylinder through their own gravity during operation. Gravity potential energy pistons and kinetic energy pistons are collectively referred to as heavy pistons. Heavy pistons include counterweight components. The density of heavy pistons must be no less than 5 g/cm³. When the heavy piston is a cylinder or liquid column, it must be elongated and have a height squared of no less than 25 times the average area of its two bases.

When the high-temperature heat source is at T1 and the low-temperature heat source is at T2, the theoretical efficiency of the Carnot engine is 1-T2/T1. In typical usage scenarios, where T2 is ambient temperature, the efficiency of the Carnot engine is positively correlated with T1. In the rotary Carnot engine of Example 2, the temperature difference between T1 and T2 depends on the pressure generated by the gravity of the heavy piston. To generate a high pressure, a dense and slender heavy piston is required. For example, to generate a pressure of two atmospheres, if the heavy piston is cylindrical, a tungsten heavy piston would need to be 1.07 meters long, while an iron heavy piston would need to be approximately 2.5 meters long.

A thinner shape can prevent the heavy piston from being too heavy. For heavy pistons of the same mass, a slender shape generates greater pressure than a short, thicker one. For a cylindrical heavy piston, the square of its height must be at least 25 times the area of its base. That is, for a regular quadrangular prism-shaped heavy piston, its height must be at least 5 times the length of its base edge to achieve optimal results. For a heavy piston composed of two cylinders, with different base sizes at each end, the square of its height must be at least 25 times the average effective pressure area.

In order to reduce the length of the heavy piston (the length of the piston is equal to the height of the piston), the following technical solutions are available:

1. A heavy piston consists of a thick portion and a thin portion. The volume of the piston is greater than the product of its length and the average effective pressure area of its two bases. The projection of the piston on a plane perpendicular to its direction of motion is greater than the average effective pressure area of its two bases.

Figure 11 is an axial cross-sectional view of a heavy piston moving vertically. The middle section of the heavy piston is a thick section, with thin sections at either end. Accordingly, the middle section of the cylinder is also thickened to form a thick section, with thin sections at either end. The diameter of the thick section is larger than any of the thin sections. The diameter of the thick section is larger than any of the thin sections. The thick section is longer than the thick section to allow room for the heavy piston to move. The thin sections are long enough to prevent them from separating from the thin sections during movement. The thin sections are airtight with the thin sections, while the thick section is not airtight with the thick section. That is, the working gas in the thin section is isolated from the working gas in the thick section, while the working gas in the thick section on both sides of the thick section is connected. Therefore, when the cylinder is in a vertical position, the weight of the heavy piston is completely supported by the pressure of the working gas in the thin sections below.

The effective air pressure area of the piston is the quotient of the pressure of the working gas on the piston and the pressure. For a cylindrical piston, the effective air pressure area is the bottom area. The average effective air pressure area is the average of the effective air pressure areas at both ends of the piston. For the heavy piston, the effective air pressure area is the cross-sectional area of the thin part, and the average effective air pressure area is the average of the cross-sectional areas of the thin parts at both ends. Due to the presence of the thick part, the volume of the heavy piston is greater than the product of its length and the average effective air pressure area of the two bottoms. The projection of the piston on a plane perpendicular to its direction of movement is the cross-sectional area of the thick part, which is greater than the average effective air pressure area of its two bottoms.

The volume of the thicker portion is larger than that of the thinner portion of the same length. Compared to a cylindrical piston of the same density, the piston can generate the same pressure due to gravity within a smaller length or working space. For example, if the cross-sectional area of the thicker portion is 50 times that of the thinner portion, a 2-centimeter-long thicker portion can generate the same pressure as a 1-meter-long thinner portion.

2. The piston is ferromagnetic and is affected by magnetic force during movement.

Potential energy pistons also include magnetic potential energy pistons.

As shown in Figure 12, the piston is made of ferromagnetic material. A magnet is positioned at the lowest point of the piston's trajectory to magnetically increase the pressure exerted by the piston on the working gas in the chamber below. The ferromagnetic material can be iron, nickel, Permalloy, or a magnet with a magnetic pole opposite to the side of the magnet pointing toward point O. The magnets include permanent magnets and electromagnets, with the permanent magnets being made of neodymium alloy.

For small rotary Carnot heat engines with a cylinder length of less than 50 cm, they can also rotate in a horizontal plane and compress the working gas using only magnetic force.

Likewise, a ferromagnetic piston can also be used in the reciprocating Carnot heat engine in the first embodiment.

3. Multi-cylinder cascade structure.

As shown in Figure 13, a multi-cylinder cascade structure consists of n cylinders arranged along the z-axis, all capable of rotating about the z-axis. The two ends of each cylinder are designated as ends A and B. The starting positions of the high-temperature and low-temperature heat sources for all odd-numbered cylinders are identical, while the starting positions of the high-temperature and low-temperature heat sources for all even-numbered cylinders are opposite those of the odd-numbered cylinders. That is, for any two adjacent cylinders, the starting position of the high-temperature heat source of the first cylinder is identical to the starting position of the low-temperature heat source of the second cylinder, and vice versa. Starting with the second cylinder, the two ends of each cylinder can be switched to an isothermal relationship with the two ends of the previous cylinder. This switchable isothermal relationship means that the ends of two adjacent cylinders can switch between an isothermal and an adiabatic relationship. In an isothermal relationship, the two ends can exchange heat, acting as high/low temperature heat sources to each other, but do not exchange heat with the outside world. At any one time, each end of each cylinder can be in an isothermal relationship with at most one other end.

For example, when end A of cylinder 1 is exposed to a high-temperature heat source, its end B switches to an isothermal relationship with end A of cylinder 2. End B of cylinder 1 becomes the high-temperature heat source for end A of cylinder 2, while end A of cylinder 2 becomes the low-temperature heat source for end B of cylinder 1. Thus, end B of cylinder 1 and end A of cylinder 2 are isothermal. Similarly, end B of cylinder i and end A of cylinder i+1 in the middle also switch to an isothermal relationship (1<i<n), serving as the high/low temperature heat source and maintaining isothermal contact. This continues until end B of cylinder n-1 and end A of cylinder n become the high/low temperature heat source and maintain isothermal contact with the low-temperature heat source, with end B of cylinder n now exposed to the low-temperature heat source. The working fluid in the A-end chamber of each cylinder is in an isothermal expansion state, while the working fluid in the B-end chamber is in an isothermal compression state.

The only external heat sources are the high-temperature heat source contacted by end A of cylinder 1 and the low-temperature heat source contacted by end B of cylinder n. If the temperature difference between ends A and B of each cylinder is dt1, dt2, dt3, …, and dtn, then the temperature difference between end A of cylinder 1 and end B of cylinder n is dt1+dt2+dt3+…+dtn. This is also the temperature difference between the high-temperature heat source contacted by end A of cylinder 1 and the low-temperature heat source contacted by end B of cylinder n.

These cascaded cylinders rotate around the z-axis, end A of cylinder No. 1 is separated from the high-temperature heat source, end B of cylinder No. i and end A of cylinder No. i+1 are switched to an adiabatic relationship (0<i<n), and end B of cylinder No. n is separated from the low-temperature heat source.

As rotation continues, end B of cylinder 1 contacts an external high-temperature heat source. End A of cylinder i and end B of cylinder i+1 in the middle switch to an isothermal relationship, serving as both high- and low-temperature heat sources, and remain isothermal until end A of cylinder n contacts an external low-temperature heat source. If the temperature difference between ends A and B of each cylinder is dt1, dt2, dt3, …, dtn (all negative values), then the temperature difference between end A of cylinder 1 and end B of cylinder n remains dt1+dt2+dt3+…+dtn.

That is, for each end of cylinder i (1<i<n), in each rotation, the isothermal expansion phase that requires contact with a high-temperature heat source switches to an isothermal relationship with cylinder i-1, and the isothermal compression phase that requires contact with a low-temperature heat source switches to an isothermal relationship with cylinder i+1.

The multi-cylinder cascade structure is equivalent to dividing a long and heavy piston into multiple sections, each of which is placed in a shorter cylinder. Under the premise of limited cylinder length, the operating temperature difference of the overall heat engine is increased, thereby improving efficiency.

Each cylinder in the multi-cylinder cascade structure may also be a multi-cavity cylinder of a crisscross shape or other types.

After solving the length problem, the frictional resistance problem remains. Compared with conventional pistons, the heavy piston has a larger weight. When the cylinder is in a non-vertical direction, the heavy piston exerts greater pressure on the cylinder wall, which will generate greater frictional resistance. In addition to the friction reduction technologies used by conventional pistons, such as air flotation, magnetic levitation, and lubricants, there are also:

1. The piston is liquid

The pistons described in the aforementioned embodiments are all free pistons, without connecting rods or other mechanical components. They only require airtight, thermally insulating, and mechanical components, without requiring hardened components. Therefore, liquid-weighted pistons can be used. Besides reducing resistance, liquid pistons also offer excellent airtightness.

The material of the liquid heavy piston can be a metal or alloy with low melting point and high density, and can contain components such as mercury, gallium, indium, bismuth, tin, lead, etc. For non-industrial use, common liquids such as water and oil can also be used as heavy pistons.

For straight cylinders, the liquid-weighted piston relies on surface tension to block the cylinder. Under surface gravity, it is only suitable for cylinders with diameters up to 6 mm. If a larger diameter is required, the area where the liquid-weighted piston operates can be constructed by connecting multiple thin tubes in parallel, each containing a section of the liquid-weighted piston. Alternatively, a cylindrical cylinder of the same cross-sectional area can be flattened to accommodate the liquid-weighted piston. In a zero-gravity environment, the liquid-weighted piston has no restrictions on cylinder diameter.

For a U-shaped cylinder or a cylinder that is partially U-shaped, as long as the liquid levels at both ends are higher than the upper edge of the lowest point of the U, it can achieve an airtight effect without relying on the surface tension of the liquid weight piston, and there is no limit to the diameter of the cylinder.

The inner surface of the cylinder includes an anti-corrosion material or coating to prevent the cylinder wall from being corroded by the liquid metal. The anti-corrosion material or coating includes metal, inorganic oxide, ceramic, glass, plastic, carbon material, high molecular polymer, etc.

If a liquid heavy piston is used in the Pozidriv cylinder, the liquid heavy piston can fill the O chamber.

2. The heavy piston includes a drag-reducing component.

The drag reduction component includes a wheel, ball bearing, rope, or connecting rod, and is used to reduce the resistance of the heavy piston as it moves within the cylinder. The drag reduction component is detachable and separate from the main piston body. All parts of the drag reduction component are located within the cylinder and are not connected to any external mechanism.

As shown in Figure 15 , the heavy piston includes a wheel or ball bearing, which contacts the inner wall of the cylinder to reduce friction. The wheel or ball bearing's location makes it difficult to achieve an airtight seal, so it is mounted on a counterweight component, and the heavy piston includes a separate airtight component. The wheel or ball bearing can be mounted on the piston or on the inner wall of the cylinder.

As shown in Figure 16, the heavy piston includes a suspension rope. The suspension rope is used to connect the counterweight component of the heavy piston and bear its gravity, thereby reducing the friction between the heavy piston and the inner wall of the cylinder. When the heavy piston moves left and right, it will be displaced up and down due to the change in the angle of the suspension rope. Therefore, relative movement perpendicular to the running direction of the heavy piston should occur between the counterweight component and the airtight component of the heavy piston. There should be space in the cylinder to accommodate the suspension rope. The length of the suspension rope from the hanging point on the inner wall of the cylinder to the point where it is connected to the counterweight component in the direction perpendicular to the central axis of the cylinder should not be less than the length of the movement range of the heavy piston. A fixed pulley fixed to the inner wall of the cylinder can be used as a suspension point to reduce the displacement of its counterweight component in the direction perpendicular to the central axis of the cylinder when the piston moves.

As shown in Figure 17, the heavy piston includes a connecting rod. Points A and B are fixed to the inner wall of the cylinder, symmetrically about the cylinder's centerline. Two equal-length rods connected to points A and B, each comprising a gear arc, mesh with each other on the cylinder's centerline, ensuring that the angles of the two rods are always symmetrical about the horizontal axis. AC = BD, so the positions of C and D are always symmetrical about the cylinder's centerline. A rod from each point C and D connects to the same point E on the heavy piston. Since the two rods are of equal length, point E always remains on the cylinder's centerline during movement of this connecting rod system. Therefore, the weight of the heavy piston is borne by the connecting rod, reducing friction between the heavy piston and the cylinder.

For a rotary Carnot heat engine, wheels, balls or ropes should be provided in both the upper and lower directions.

The suspension rope or connecting rod does not extend beyond the cylinder.

3. The piston includes an airtight membrane.

As shown in Figure 18, the airtight membrane is an airtight, soft film that can be made of graphene, metal, carbon fiber, polymer materials, glass, plastic, rubber, etc. The airtight membrane is used to improve airtightness without increasing friction, that is, to reduce friction while meeting airtightness requirements.

One use case for the airtight membrane is a cylindrical shape with one end closed and the other open, similar to a sock. The open end of the airtight membrane is connected to the inner wall of the cylinder, so that the connection points can continuously form a closed curve, and the central axis of the cylinder passes through the closed curve. The airtight membrane then separates the working fluid gas in the cylinder into two chambers. When the pressure of the working fluid gas in one of the chambers increases, the airtight membrane is pushed toward the other chamber, compressing the working fluid gas in the other chamber.

A second use case for the airtight membrane is to enclose airbags. At least two cylindrical airbags composed of the airtight membrane and filled with working gas are inserted into the cylinder, neither of which is inflated. These airbags completely occupy the interior space of the cylinder. These at least two airbags are then equivalent to at least two chambers separated by a piston. When the pressure within one of the airbags increases, it will increase in length and compress the other airbags.

The airtight membrane is an airtight component that acts like a reciprocating lightweight free piston, dividing the working gas in the cylinder into multiple chambers. As the gas pressure in each chamber changes, the separation point moves, changing the volume of each chamber within the cylinder. The airtight membrane offers high airtightness and low motion resistance, making it an ideal airtight component. If a counterweight, hardening component, or thermal insulation component is required, these can be added separately. The combination of one or more of these three components and the airtight membrane is called an airtight membrane piston. The airtight membrane in Figure 18 is connected to a counterweight component to form a heavy piston.

A common piston in a typical heat engine transmits gas pressure through a rod. The airtight membrane can also be connected to a common piston connected to a rod to achieve the same function. In this case, the airtight membrane is the airtight component, and the common piston serves only as a hardened part. It does not need to be in close contact with the cylinder wall, resulting in lower frictional resistance.

The wheel, ball, sling, connecting rod or airtight membrane, even if fixed on the inner wall of the cylinder, is also part of the piston.

Example 4: Pendulum Carnot Heat Engine

1. Planar pendulum Carnot heat engine

As shown in Figure 21, a fully enclosed cylinder with an integrated outer wall oscillates vertically. A heavy piston within the cylinder divides the working gas within the cylinder into two chambers. Similar to the rotary Carnot heat engine, when the cylinder moves to a vertical angle, the heavy piston exerts maximum pressure on the working gas within the chamber below it. The lower end of the cylinder is the heat-conducting end. A high-temperature heat source is placed directly below, and low-temperature heat sources are placed at the highest points of the swing range on either side, forming a Carnot heat engine. As the cylinder oscillates back and forth, the working gas within it begins an isothermal expansion process each time it contacts the high-temperature heat source at its lowest point. After separating from the high-temperature heat source, it enters an adiabatic expansion process. When it reaches the highest point and begins contacting the low-temperature heat source, it enters an isothermal compression process, and after separating from the low-temperature heat source, it enters an adiabatic compression process. Each swing cycle consists of two Carnot cycles.

2. Conical swing Carnot heat engine

As shown in Figure 22, a cylinder similar to that of a planar pendulum Carnot engine rotates on a conical surface, the bottom of the cone being non-horizontal. When the heat-conducting end of the cylinder reaches its lowest position, the heavy piston in the cylinder exerts maximum pressure on the working gas in the chamber below it. A high-temperature heat source is placed at the beginning of the rise phase after the heat-conducting end reaches its lowest position, and a low-temperature heat source is placed at the beginning of the fall phase after the heat-conducting end reaches its highest position, thus forming a Carnot engine. During each rotation cycle, the working gas in the chamber between the heat-conducting end and the piston in the cylinder undergoes an isothermal expansion process when in contact with the high-temperature heat source, an adiabatic expansion process after separation, an isothermal compression process when in contact with the low-temperature heat source, and an adiabatic compression process after separation.

A plurality of cylinders can be fixed on the conical surface to provide continuous power.

The cylinder is connected to a mechanism that performs external work, and the heat engine performs external work through the movement of the cylinder. The movement of the cylinder includes one-dimensional movement, two-dimensional movement, and three-dimensional movement. The cylinder in Example 1 has one-dimensional movement, the cylinder in Example 2 has two-dimensional movement, and the cylinder of the conical pendulum Carnot heat engine in this embodiment has three-dimensional movement.

The cylinder is capable of periodic motion, wherein each period of the motion is an integer multiple of the working cycle of the working fluid gas within the cylinder. The cylinder periodically changes its contact relationship with the high/low temperature heat source. The periodic changes include: 1. periodic motion of the cylinder relative to the high/low temperature heat source; 2. periodic changes in the temperature or range of the high/low temperature heat source; and 3. periodic changes in the connection/disconnection relationship between the temperature-variable chamber and the hot or cold chamber within the cylinder.

For the cylinders in the first and second embodiments and the conical pendulum Carnot heat engine, the motion period of each cylinder includes one Carnot cycle. For the cylinders in the planar pendulum Carnot heat engine, the motion period of each cylinder includes two Carnot cycles.

The apex angle of the conical surface can be any angle. When it is 180°, the conical pendulum Carnot heat engine becomes the rotary Carnot heat engine. For the same cylinder and piston, when the apex angle of the conical surface is 180° and the motion is in a vertical plane, the temperature difference between the applicable high-temperature and low-temperature heat sources is maximized, ensuring that the high-temperature heat source and the working gas are isothermal at the end of adiabatic compression, and the low-temperature heat source and the working gas are isothermal at the end of adiabatic expansion, thereby ensuring that the working cycle is a Carnot cycle. Consequently, the heat engine efficiency is maximized. The apex angle of the conical surface can be adjusted to match high and low-temperature heat sources with different temperature differences. Similarly, for the rotary Carnot heat engine and the Carnot heat engines of Examples 6, 7, and 8, the angle between the cylinder or the plane in which the cylinder rotates and the gravitational field can be adjusted to match high and low-temperature heat sources with different temperature differences.

Example 5: Heat Pump

This embodiment provides a method for converting internal energy into mechanical energy through a cylinder, comprising a forward or reverse cycle of the following four steps: 1. isothermal expansion of the working gas in the cylinder; 2. adiabatic expansion of the working gas in the cylinder; 3. isothermal compression of the working gas in the cylinder; 4. adiabatic compression of the working gas in the cylinder. The cylinder is any heat engine or heat pump cylinder other than an internal combustion engine in this application. When operating in the forward cycle, the method is a heat engine method, and when operating in the reverse cycle, the method is a heat pump method.

As shown in Figure 23, the clockwise steps represent the forward cycle, while the counterclockwise steps represent the reverse cycle. Those skilled in the art will understand that the Carnot cycle is a reversible cycle. The forward cycle is a heat engine cycle, while the reverse cycle is a heat pump cycle. A heat pump operates by receiving work from the outside world and transferring heat from a low-temperature heat source to a high-temperature heat source, which can be used for cooling or heating. A heat engine converts internal energy into mechanical energy, while a heat pump converts mechanical energy into internal energy.

In addition to internal combustion engines, all heat engines described in this application can be reversed to become heat pumps. A Carnot heat engine and heat pump are integrated. That is, the heat pump has the same structure as the aforementioned heat engines. All of the aforementioned heat engines are Carnot heat engines, and their operation is reversible: in forward operation, they function as heat engines, and in reverse, they function as heat pumps.

The heat pump includes an energy storage device for storing potential energy. During the heat pump's operating cycle, the potential energy of the energy storage device is first increased by receiving external work, and then released by absorbing heat from a low-temperature heat source and/or releasing heat to a high-temperature heat source. During each operating cycle of the heat pump, the maximum potential energy stored in the energy storage device is no less than half the external work received by the heat pump. This potential energy includes gravitational potential energy, electric potential energy, magnetic potential energy, and other potential energy.

The heat pump includes a cylinder that is movable. The heat pump receives external work through the movement of the cylinder. The cylinder's motion includes one-dimensional, two-dimensional, and three-dimensional motion, specifically reciprocating and rotational motion. The motion is periodic, with each period being an integer multiple of a working cycle of the working fluid gas within the cylinder.

Taking the rotary Carnot heat engine in Example 2 as an example, its reverse operation method is to connect the mechanism for external power input to the cylinder, and the external work drives the cylinder to rotate clockwise to receive the external work. The working fluid gas in each chamber begins an adiabatic expansion process at the lowest point, contacts the low-temperature heat source on the left, begins an isothermal expansion process and absorbs heat, leaves the low-temperature heat source at the top, enters an adiabatic compression process, contacts the high-temperature heat source on the right, begins an isothermal compression process and releases heat. The direction of rotation and the order of the above four processes are opposite to those when operating as a heat engine, so that heat can be transferred from the low-temperature heat source to the high-temperature heat source. The piston acts as an energy storage device, receiving external work in each cycle to rise, storing gravitational potential energy, and then moving downward by releasing gravitational potential energy, while absorbing heat from the low-temperature heat source and releasing heat to the high-temperature heat source.

Example 6: Annular Tube Carnot Heat Engine

The present invention provides a heat engine, comprising a cylinder, wherein the cylinder is an annular tube shape and at least one piston is arranged in the cylinder. The piston in the cylinder can return to an initial position after moving one circle.

As shown in Figure 6, a straight tube with two open ends is bent into a circular shape and connected end to end to form a ring tube. The cylinder in this embodiment is ring-shaped. This ring-shaped cylinder is also a one-piece, fully enclosed structure. The cylinder contains a working fluid gas. The cylinder contains n identical pistons, which divide the working fluid gas into n gas segments, with each segment containing an equal amount of gas. n >= 4.

The piston within the cylinder can return to its initial position after one full rotation. That is, the piston can return to its initial position after one full rotation counterclockwise or clockwise. The piston includes a magnet. A magnet is used outside the cylinder to guide all pistons within the cylinder in a counterclockwise direction. For ease of analysis, n = 200, making each air segment very short and negligible positional differences between the beginning and end of each air segment.

The cylinder is fixed on a vertical surface, and an x-y rectangular coordinate system is established with the center of the annular tube as the origin. The movement of each piston is affected by the tangential component of gravity on its own trajectory and the pressure of the two preceding and succeeding gas segments. The pressure and temperature of each gas segment are minimum and its volume is maximum at the highest point of the annular tube; the pressure and temperature are maximum and its volume is minimum at the lowest point of the annular tube. Each gas segment undergoes an adiabatic expansion process when moving upward, and an adiabatic compression process when moving downward.

A high-temperature heat source at T1 is set in the fourth quadrant, allowing each gas segment to absorb heat from the high-temperature heat source when passing through the fourth quadrant. A low-temperature heat source at T2 is set in the second quadrant, allowing each gas segment to release heat to the low-temperature heat source when passing through the second quadrant. Each gas segment cannot exchange heat with the outside world in the first and third quadrants. T1 > T2.

For any of the aforementioned gas segments, when entering the fourth quadrant from the third quadrant, the adiabatic compression process changes to an isothermal expansion process; when entering the first quadrant, it changes to an adiabatic expansion process; when entering the second quadrant, it changes to an isothermal compression process; and when entering the third quadrant, it changes to an adiabatic compression process. Its working cycle is the Carnot cycle.

Obviously, when the pistons are all stationary, the pistons can also be caused to start rotating counterclockwise by heating the gas section in the fourth quadrant.

The temperature of each air segment in the first quadrant decreases counterclockwise from T1 to T2. The temperature of the air segments in the second quadrant is all at T2. The temperature of the air segments in the third quadrant increases counterclockwise from T2 to T1. The temperature of the air segments in the fourth quadrant is all at T1. In other words, the air segments to the right of the y-axis have a higher temperature and a larger volume than the air segments at the same height to the left of the y-axis. Therefore, there are more pistons on the left side of the y-axis than on the right side, and the combined gravitational force is greater. The air segments directly below the annular tube experience greater pressure from the left side, with the combined force acting to the right. Consequently, these pistons maintain counterclockwise motion and gradually accelerate.

The piston includes a magnet that can be used to conduct the piston's kinetic energy out of the cylinder through electromagnetic action. One method is to wrap a wire around or near the cylinder to generate electricity when the piston passes. A second method is to place a movable magnet near the cylinder, which will drive the magnet to move when the piston passes, thereby conducting kinetic energy. Those skilled in the art can propose more methods for conducting the piston's kinetic energy without any creative thinking or effort, and these methods are all within the scope of protection of this application.

In addition, when there is friction or viscosity between the piston and the cylinder, and the cylinder can rotate around the center of the ring, the movement of the piston can drive the cylinder to rotate, and work is performed externally through the rotation of the cylinder.

Example 7: Airflow Carnot Heat Engine

The density of the pistons in the cylinder of the aforementioned annular Carnot heat engine corresponds to the density distribution of the working gas in the cylinder, effectively abstracting the mass of the working gas. Returning the piston's mass to the working gas, considering the working gas as having mass, allows for a simpler design.

The piston in all Carnot heat engines in this application is an abstraction of the mass of the working gas. When the density of the working gas is large enough, for example, the density of xenon at 30 atmospheres is close to one-fifth of that of water, the piston can be omitted.

As shown in Figure 7, a circular cylinder is fixed on a vertical surface. It contains a working gas with mass, whose pressure is determined by both the thermal motion of the molecules and gravity. When the working gas is stationary, due to gravity, the pressure at each x,y coordinate in the cylinder is negatively correlated with the y value.

A high-temperature heat source with a temperature of T1 is set in the fourth quadrant, allowing the working gas to absorb heat from the high-temperature heat source when passing through the fourth quadrant. A low-temperature heat source with a temperature of T2 is set in the second quadrant, allowing the working gas to release heat to the low-temperature heat source when passing through the second quadrant. The working gas in the first and third quadrants cannot exchange heat with the outside world. T1 > T2. Because the working gas in the fourth quadrant absorbs heat and expands, its density is lower than that in the third quadrant. The working gas in the second quadrant releases heat and compresses, making its density higher than that in the first quadrant. The weight of the working gas on the left side of the y-axis is greater than that on the right side of the y-axis. The working gas at the bottom of the cylinder experiences a greater pressure on the left side than on the right side, causing it to flow rightward. This means that the working gas in the cylinder begins to flow counterclockwise.

Similar to the aforementioned annular Carnot heat engine, for each section of the working gas, as it moves from the third quadrant into the fourth quadrant, the process changes from adiabatic compression to isothermal expansion; then, as it enters the first quadrant, it becomes an adiabatic expansion; then, as it enters the second quadrant, it becomes an isothermal compression; and finally, as it enters the third quadrant, it becomes an adiabatic compression. Its operating cycle is a Carnot cycle. The working gas maintains counterclockwise motion and gradually accelerates.

A fan is added to the cylinder so that the airflow can generate work for the fan. A generator can be connected to the fan to conduct electricity outside the cylinder, or a magnet or coil can be connected to the fan to conduct the fan's kinetic energy outside the cylinder through electromagnetic interaction with the magnet or coil outside the cylinder. Those skilled in the art can devise additional methods for conducting the kinetic energy of the working gas without requiring creative thought or effort, and these methods are all within the scope of protection of this application.

When airflow is slow, the high-temperature heat source in the fourth quadrant can transfer some heat to the working gas in the third quadrant, while the low-temperature heat source in the second quadrant can also absorb heat from the working gas in the first quadrant. This blurs the boundary between the adiabatic and isothermal processes, affecting efficiency. This problem can be addressed by adding heat-blocking channels at both the highest and lowest points of the cylinder.

The cylinder has a heat-blocking channel, and the working medium gas in the cylinder can pass through the heat-blocking channel, but cannot conduct heat against the direction of airflow through the heat-blocking channel.

The heat-blocking channel is a particularly thin section in the cylinder, and its cross-sectional area does not exceed one-fifth of the average cross-sectional area of the cylinder. Therefore, the speed of the working gas flow through the heat-blocking channel is more than five times that of the flow through the rest of the cylinder. Increasing the speed of the airflow can significantly prevent heat from being transferred in the direction opposite to the airflow. Therefore, the heat-blocking channel between the third and fourth quadrants can prevent the high-temperature heat source in the fourth quadrant from transferring heat to the working gas in the third quadrant, and the heat-blocking channel between the first and second quadrants can prevent the low-temperature heat source in the second quadrant from absorbing heat from the working gas in the first quadrant.

Due to the low density of the gas, the power-to-volume ratio of a practical airflow Carnot heat engine is low. While increasing the density of the working gas, such as xenon or mercury vapor, is possible, ideal power can be achieved by increasing the working gas pressure and increasing the size of the cylinder. For example, a cylinder several kilometers high can be constructed based on the terrain. The cylinder in this embodiment does not need to be circular; it can be used as long as it forms a loop.

Example 8: Rotating Ring Tube Carnot Heat Engine

As shown in FIG8 , a rotating annular Carnot heat engine also includes an annular cylinder as described in Example 6, wherein the cylinder contains a mass working fluid gas as described in Example 7. The cylinder is capable of rotating about its center O in a vertical plane.

The cylinder is an annular tube with at least two valves within it. These valves can be opened and closed automatically or under control. When closed, the working gas in the cylinder cannot pass through the valves. When all valves are open, the working gas in the cylinder can circulate, i.e., the working gas can return to its original position after completing a full cycle in the annular tube. The valves are thermally insulated.

There are n valves in the cylinder, which divide the cylinder into n equally spaced segments. n >= 2. For ease of description, assume n = 12.

Initially, the cylinder is stationary, and the 12 valves are positioned between 1 and 12 o'clock on a clock. The valves are numbered according to their respective clock positions. For example, the valve at 1 o'clock is designated valve 1, the valve at 2 o'clock is designated valve 2, and so on, the valve at 12 o'clock is designated valve 12. Valve 6 is closed, and the remaining valves are open.

A high-temperature heat source at T1 is set in the fourth quadrant, allowing the working gas to absorb heat from the high-temperature heat source as it passes through the fourth quadrant. A low-temperature heat source at T2 is set in the second quadrant, allowing the working gas to release heat to the low-temperature heat source as it passes through the second quadrant. The working gas in the first and third quadrants cannot exchange heat with the outside world. T1 > T2. Because the working gas in the fourth quadrant absorbs heat and expands, its mass is smaller than that in the third quadrant. Because the working gas in the second quadrant releases heat and compresses, its mass is greater than that in the first quadrant. The mass of the working gas on the left side of the y-axis is greater than that on the right side of the y-axis. The pressure on the left side of valve 6 is greater than the pressure on the right side. The resulting force is to the right, pushing the cylinder counterclockwise.

When valve 6 leaves the 6 o'clock position, valve 7 closes, and then valve 6 opens. The pressure on the left side of valve 7 is greater than the pressure on the right side, causing the cylinder to continue to rotate counterclockwise. When valve 7 passes the 6 o'clock position, valve 8 closes, and then valve 7 opens. This process repeats, with each valve closing at the 7 o'clock position and opening at the 6 o'clock position, driving the cylinder to rotate counterclockwise and perform external work.

At any given moment, at least one of the valves is closed. After each switch, a section of the working gas enters the fourth quadrant from the third quadrant, transitioning from an adiabatic compression process to an isothermal expansion process. Upon entering the first quadrant, it transitions to an adiabatic expansion process. Upon entering the second quadrant, it transitions to an isothermal compression process. Finally, upon entering the third quadrant, it transitions to an adiabatic compression process. The operating cycle is a Carnot cycle.

In some embodiments, the cylinder lacks a valve and instead includes a blocking device. This blocking device serves to retard the flow of air within the annular tube, but does not completely block it. One method for implementing this blocking device is to provide multiple, equidistant, semi-enclosed baffles. These baffles do not completely block the annular tube, but do increase resistance to the airflow. The reaction force of this resistance acts as a driving force on the baffles, driving the cylinder to rotate and perform external work.

Example 9: Sandwich combustion chamber

The Carnot heat engines described in the above embodiments are all external combustion engines. Compared with internal combustion engines, one of the disadvantages of external combustion engines is that combustion occurs outside the cylinder, and the heat generated cannot be fully transferred to the working fluid, but a large part is dissipated. To reduce heat loss, the present invention also includes:

The cylinder includes a combustion chamber, and the combustion chamber includes an interlayer. The space in the interlayer is communicated with the space in the cylinder to fully utilize the heat of the heat source and avoid loss.

As shown in Figure 9, the cylinder includes a combustion chamber with an interlayer within its outer wall. The space within this interlayer communicates with the interior of the cylinder, and the gas within this interlayer serves as the working gas within the cylinder. When the fuel burns in the combustion chamber, the heat released must be transferred to the external environment, and the shortest straight path must pass through the working gas. Therefore, over 90% of this heat is transferred to the working gas, with minimal heat loss.

The combustion chamber is part of the cylinder and moves with it. Taking the reciprocating Carnot heat engine of Example 1 as an example, its left and right heat-conducting ends comprise the combustion chamber. When the combustion chamber moves to the high-temperature heat source position, fuel is automatically added to the combustion chamber and ignited, creating a high-temperature heat source. When the combustion chamber leaves the high-temperature heat source position, combustion in the combustion chamber is extinguished.

It is obvious that a high temperature heat source can also be formed by adding a high temperature substance to the combustion chamber. Similarly, a low temperature heat source can be formed by adding a low temperature substance to the combustion chamber.

In some embodiments, compressed gas is used as fuel. When a low-temperature heat source is needed, compressed gas is injected into the combustion chamber. The compressed gas expands and absorbs heat, providing a cooling effect. When a high-temperature heat source is needed, the compressed gas is ignited. The compressed gas includes various combustible gases such as hydrogen, ammonia, hydrocarbons, ethers, alcohols, aldehydes, and carbon monoxide, as well as mixtures of multiple such gases and oxidants.

The heat exchanger is a complex sandwich structure, the sandwich also comprising the heat exchanger.

Example 10: Temporary Cavity Internal Combustion Engine

The internal combustion engine cannot yet be converted into a standard Carnot heat engine, but by improving its internal structure, its working cycle can be made closer to the Carnot cycle, especially by converting the power stroke into a combination of isothermal expansion and adiabatic expansion, which is closer to a reversible process, thereby improving efficiency.

The gasoline engine's operating cycle consists of four strokes. The third is the power stroke. After the piston reaches dead center, the compressed fuel-air mixture ignites, pushing the piston and producing work. Due to the short combustion time, this process consists of an isochoric heating process and an adiabatic expansion process. The isochoric heating process is not reversible, resulting in low power efficiency. To improve this efficiency, the mixture can be ignited multiple times, making the multiple isochoric heating and adiabatic expansion processes more similar to isothermal expansion.

The present invention provides an internal combustion engine, comprising a cylinder, wherein the cylinder comprises a piston, and when the piston reaches a dead point, the cylinder can be divided into at least two areas, wherein when a mixture in any one of the areas is ignited, the mixture in the other areas cannot be immediately ignited.

As shown in Figure 10, the piston's axial cross-section is stepped. The cylinder's axial cross-section is also stepped. As the piston moves deeper into the cylinder, the space within the cylinder is divided into two regions: chamber A and chamber B. Ignition of the mixture in chamber A will not ignite the mixture in chamber B, and ignition of the mixture in chamber B will not ignite the mixture in chamber A.

The mixture in chamber A is ignited. After the mixture in chamber A is ignited, it pushes the piston upward until chambers A and B are connected. The combustion in chamber A, or the high-temperature gases generated after combustion, ignite the mixture in chamber B. This achieves a double ignition of the mixture in the cylinder, making the two equal-volume heating and adiabatic expansion processes more similar to isothermal expansion overall, thereby improving the efficiency of the gasoline engine.

That is, the interior of the cylinder includes at least two spatial regions. During the operation of the cylinder, the at least two spatial regions are connected during at least one period and isolated during at least another period. The operation of the cylinder is cyclical. In each cycle of the cylinder's operation, the at least two spatial regions are connected during at least one period and isolated during at least another period. The at least two spatial regions each form a cavity when isolated and belong to the same cavity when connected. In this application, any one of the at least two spatial regions is referred to as a temporary cavity.

In some embodiments, an isobaric device is placed between chambers A and B to maintain equal pressure in chambers A and B, preventing sudden pressure changes when they are connected. One design for the isobaric device involves adding a cylindrical channel between chambers A and B. This channel contains a free piston, which isolates the gases in chambers A and B and moves within the channel in response to pressure changes, changing the volumes of chambers A and B. Specifically, when the pressures in chambers A and B differ, the free piston moves toward the lower-pressure chamber, lowering the pressure in the higher-pressure chamber and increasing it, thus maintaining equal pressure in the two chambers. The isobaric device is thermally adiabatic.

Obviously, by making the piston and the cylinder into more complex shapes, the mixture in the cylinder can be divided into more areas when the piston reaches the dead center, thereby realizing multiple ignitions of the mixture, making the multiple isochoric heating and adiabatic expansion processes generally closer to isothermal expansion, thereby further improving the efficiency of the gasoline engine.

Example 11: Reversible internal combustion engine

The present invention provides an internal combustion engine comprising a cylinder. The internal combustion engine operates by burning fuel within the cylinder to produce external work, wherein the combustion comprises a reversible chemical reaction. The chemical equilibrium of the reversible chemical reaction is affected by temperature, such that a decrease in temperature shifts the chemical equilibrium in a positive direction.

The reversible chemical reaction begins at a high temperature, initially inhibiting the forward reaction. As the temperature gradually decreases, the forward reaction is promoted until the forward reaction is completely completed. A reversible chemical reaction is also a reversible process that conforms to the Carnot cycle.

For example, when carbon monoxide is used as fuel and combines with oxygen to form carbon dioxide, carbon dioxide will also decompose into carbon monoxide and oxygen at high temperatures. This reaction is reversible, and its chemical equilibrium is related to temperature.

As shown in Figure 24, this is a four-stroke internal combustion engine fueled by carbon monoxide. It consists of two cylinders. A passageway connects the two cylinders at their bases, and a valve G is located on this passageway. Valve G controls whether the two cylinders are connected or disconnected. Each cylinder contains a piston, which is fixed together and moves synchronously. The two pistons are connected to a flywheel via a rod.

During the intake stroke, G is closed and one of the two cylinders inhales carbon monoxide while the other inhales excess oxygen (which can also be air).

During the compression stroke, carbon monoxide and oxygen are compressed separately and adiabatically, raising their temperatures to a high temperature, Th, greater than 700°C. Because Th is above the ignition point of the fuel, the fuel and oxygen must be compressed separately and cannot be mixed before compression to prevent premature combustion.

At the beginning of the power stroke, G opens, connecting the two cylinders, and carbon monoxide and oxygen react. The reaction equation is:

2CO+O ₂ ⇌2CO ₂

During the power stroke, the two pistons move outward. The heat released by the chemical reaction described above causes the gas temperature and pressure in the two cylinders to be higher than when they reach the same position through adiabatic expansion. If the chemical reaction proceeds too quickly, causing the temperature to rise, the chemical equilibrium of the chemical reaction will shift to the left, thereby slowing down the release of heat. Conversely, if the chemical reaction proceeds too slowly, causing the temperature to drop too quickly, the chemical equilibrium of the chemical reaction will shift to the right, accelerating the release of heat. In other words, the chemical reaction can provide negative feedback to temperature changes, thereby allowing the temperature to drop smoothly while the chemical equilibrium of the chemical reaction gradually shifts to the right. From the perspective of a quasi-static process, this process is an expansion process in which the temperature of the heat source gradually decreases and the temperature of the working gas also decreases synchronously. The heat source and the working gas are always isothermal, which is equivalent to a series of isothermal expansion processes with very short periods of time in which the temperature gradually decreases. It is a reversible process.

After the reaction of carbon monoxide and oxygen is completed, no more heat is released and the power stroke enters the adiabatic expansion process.

After the power stroke, the exhaust gas is discharged during the exhaust stroke and the next cycle begins.

In addition to the oxidation of carbon monoxide, other reversible chemical reactions can also be used to achieve similar internal combustion engines, such as ammonia decomposition and the Sabatier reaction. To ensure that the combustion process is a reversible reaction, the molecular weight of the fuel is less than 100.

In the carbon monoxide oxidation reaction, if the amount (moles) of reactants exceeds the amount of products, pressure will also affect the chemical equilibrium. This can be achieved by adding additional reactants simultaneously, allowing multiple reactions to occur simultaneously. By making the amount (moles) of reactants less than the amount of products in the additional reactions, the effect of pressure on the chemical equilibrium can be balanced.

Example 12: Thermal Conductivity Switching

Temporary cavities are also used in the cylinders of external combustion engines to allow the working gas in the cylinder to be flexibly switched between isothermal and adiabatic states.

As shown in Figure 14, a cylinder is divided into three chambers: left, center, and right. Each chamber contains a working fluid. A passageway connects the left and center chambers, and between the center and right chambers. Each passageway has a valve, referred to as the left and right valves. An isobaric valve connects the left and center chambers, and between the center and right chambers, respectively. Each isobaric valve contains a piston, referred to as the left and right pistons. A piston connects the center chamber to the outside world, referred to as the center piston. The center piston is connected to the flywheel via a piston rod. These pistons are thermally insulated.

The cylinder is a component of a heat engine or a heat pump.

The cylinder includes a constant temperature chamber and a variable temperature chamber. A channel and an isobaric device are located between the variable temperature chamber and the constant temperature chamber. The channel includes a valve that controls whether the variable temperature chamber and the constant temperature chamber are connected. The isobaric device equalizes the pressure in the constant temperature chamber and the variable temperature chamber. If the cylinder includes multiple constant temperature chambers with different temperatures, the variable temperature chamber can only be connected to one of the constant temperature chambers at any one time. Both the constant temperature chamber and the variable temperature chamber are temporary chambers.

The left, middle and right chambers are temporary chambers. The left and right pistons ensure that the pressures in the left, middle and right chambers are always the same. When the flywheel rotates, the middle piston reciprocates up and down. Regardless of whether the left and right valves are open, the working fluid gas in the three chambers is in an adiabatic compression process when the middle piston descends, and in an adiabatic expansion process when the middle piston rises. Each cycle only includes these two adiabatic processes, there is no heat exchange with the outside world, the work done to the outside is equal to the work received from the outside world, and the net work is zero. At this time, the cylinder is an adiabatic machine.

The cylinder includes a hot chamber, a cold chamber, and a variable temperature chamber, wherein the hot and cold chambers are constant temperature chambers. A hot end channel and a hot end isobaric device are located between the variable temperature chamber and the hot chamber, while a cold end channel and a cold end isobaric device are located between the variable temperature chamber and the cold chamber. Each hot end channel and the cold end channel have a valve. The valve on the hot end channel controls whether the variable temperature chamber is in communication with the hot chamber, while the valve on the cold end channel controls whether the variable temperature chamber is in communication with the cold chamber. During operation of the cylinder, the variable temperature chamber is not in communication with both the hot and cold chambers at the same time. During operation of the cylinder as a heat engine component, the hot chamber is exposed to a high-temperature heat source, maintaining the working gas temperature therein at a high temperature, T1. The cold chamber is exposed to a low-temperature heat source, maintaining the working gas temperature therein at a low temperature, T2. When the variable temperature chamber is in communication with the hot chamber, its temperature is maintained at T1; when it is in communication with the cold chamber, its temperature is maintained at T2. When the variable temperature chamber is not in communication with either the hot or cold chamber, the working gas temperature therein can be varied. When the cylinder operates as a heat pump component, it can transfer heat from the cold chamber to the hot chamber by receiving external work, causing the cold chamber to absorb heat from the outside world and release heat to the outside world. The hot-end isobaric device can equalize the pressure of the hot chamber and the variable temperature chamber, while the cold-end isobaric device can equalize the pressure of the cold chamber and the variable temperature chamber. The hot/cold-end isobaric devices are thermally insulated.

A high-temperature heat source at temperature T1 is added to the left chamber. It transfers heat to the left chamber, maintaining the temperature there at T1. A low-temperature heat source at temperature T2 is added to the right chamber, absorbing heat from the right chamber, maintaining the temperature there at T2. The original adiabatic engine becomes a heat engine. The left chamber is the hot chamber, the right chamber is the cold chamber, and the center chamber is the variable temperature chamber. The channel between the left and center chambers is the hot end channel, and the channel between the right and center chambers is the cold end channel.

By opening/closing the left and right valves, the working gas in the middle cavity can be switched between isothermal and adiabatic processes. The working cycle is as follows:

With both the left and right valves closed, the temperature of the middle chamber reaches its highest point, T1, when the middle piston descends to its lowest point. At this point, the left valve is opened, connecting the left and middle chambers. The middle piston then begins to rise, connecting the middle and left chambers to form a single chamber. The working gas within these chambers comes into contact with the high-temperature heat source, receiving heat replenishment. During the expansion process, the temperature remains at T1, making this isothermal expansion. This means that part of the adiabatic expansion process of the original adiabatic machine is converted to isothermal expansion. The working gas in the right chamber also expands isothermally at temperature T2. Before closing the left valve, the left piston is moved to the middle of its range of motion to ensure sufficient room for movement while the left valve is closed. Because the pressures on both sides of the left piston are equal, this movement requires no work.

Before the middle piston reaches its highest point, the left valve is closed, isolating the middle chamber from the left chamber. The working gas in the middle chamber no longer contacts the high-temperature heat source and enters an adiabatic expansion process. The working gas in the left chamber continues to expand isothermally until the middle piston reaches its highest point, and the temperature of the middle chamber drops to its lowest point, T2. At this point, the right valve is opened, connecting the right chamber with the middle chamber. The middle piston then begins to descend, connecting the middle and right chambers to form a single chamber. The working gas within these chambers contacts the low-temperature heat source, releasing heat and maintaining the temperature at T2 during compression. This compression process is isothermal. In other words, a portion of the original adiabatic compression process is converted to isothermal compression. The working gas in the left chamber also undergoes an isothermal compression process at temperature T1. Before the right valve is closed, the right piston is moved to the middle of its range of motion, again without performing any work.

Before the middle piston reaches its lowest point, the right valve closes, isolating the middle and right chambers. The working gas in the middle chamber no longer contacts the low-temperature heat source and enters adiabatic compression. The working gas in the right chamber continues to undergo isothermal compression until the middle piston reaches its lowest point, completing a full cycle. This cycle consists of four steps in the variable temperature chamber: isothermal expansion, adiabatic expansion, isothermal compression, and adiabatic compression. In the left and right chambers, it consists of isothermal expansion and isothermal compression, all of which are reversible. This cycle is called the Carnot cycle. Reversing this cycle creates a heat pump.

The original adiabatic engine is converted into a Carnot engine by converting the initial portion of the adiabatic expansion/compression process of the original adiabatic engine into an isothermal expansion/compression process. Other portions of the adiabatic expansion/compression process of the original adiabatic engine can also be modified, and multiple modifications are possible. After these modifications, as long as the operating cycle is reversible, it is a Carnot cycle. The Carnot engine can be restored to an adiabatic engine after removing the high/low temperature heat source.

The upper end of the cylinder is open, and the working medium gas is separated from the outside by a middle piston. An airtight membrane piston can be used as the middle piston to prevent gas leakage.

In some embodiments, the flywheel and piston rod are removed, and the upper end of the cylinder is sealed, forming a fully enclosed, integrated structure. If the cylinder can move up and down and the middle piston is a heavy piston, the heat engine becomes the reciprocating Carnot heat engine described in Example 1. If the cylinder cannot move, a magnet or coil can be added to the middle piston to output the middle piston's kinetic energy through the cylinder wall via electromagnetic action.

Obviously, the cylinder can also be used in the Carnot heat engine/heat pump of embodiments 2, 4, 6, 7, and 8. In some embodiments, each hot/cold chamber can correspond to multiple variable temperature chambers. A valve and an isobar are provided between each hot/cold chamber and each variable temperature chamber. Each hot/cold chamber cannot be connected to multiple variable temperature chambers at the same time, and different isobars connected to each hot/cold chamber do not operate simultaneously to avoid affecting the temperature and pressure differences in the multiple variable temperature chambers.

The above are some embodiments of the present invention. Obviously, these are only some typical use cases and do not fully cover the technology of the present invention. Those skilled in the art can also combine more embodiments based on these embodiments without any creative thinking and effort, and these embodiments are all within the scope of protection of this application.

Industrial Applicability

The heat engine and heat pump disclosed in this invention not only have the highest theoretical level of heat-to-work conversion efficiency, but also have a simpler structure than all heat engines except ramjets. By simply attaching a number of fully enclosed straight cylinders with pistons in the middle to a variety of motion mechanisms, various heat engines and heat pumps can be conveniently and flexibly constructed. They have low production costs, low operating noise, and can operate at low temperature differentials, making them superior to Stirling heat engines/heat pumps on the market. As a heat engine, it has a higher power density than a steam turbine, is compatible with a variety of fuels, and can quickly self-start without preheating, making it particularly suitable for flexible power generation scenarios.

Claims (11)

A cylinder comprising at least one piston, wherein the piston has at least one of the following characteristics: 1) The piston includes a drag reducing component; 2) The square of the height of the piston shall not be less than 25 times the average effective pressure area of its two bases; 3) The volume of the piston is greater than the product of its length and the average effective pressure area of the two bottoms; 4) The piston is an airtight membrane piston. A cylinder is characterized in that the outer wall of the cylinder is an integrated fully enclosed structure. The cylinder according to claim 1 and/or 2, characterized in that at least a portion of the cylinder can be switched between a heat-insulating state and a heat-conducting state. A cylinder is characterized in that the interior of the cylinder includes at least two space areas. During the operation of the cylinder, the at least two space areas are connected in at least one period and isolated in at least another period. A heat engine, characterized in that it comprises a cylinder, wherein the cylinder is the cylinder described in claim 1 and/or 2 and/or 3 and/or 4. The heat engine according to claim 5 is characterized in that the heat engine includes an energy storage device for storing potential energy, and in the working cycle of the heat engine, the potential energy of the energy storage device is first increased by absorbing heat from a high-temperature heat source and/or releasing heat to a low-temperature heat source, and then work is performed externally by releasing the potential energy. The heat engine as described in claim 5 is characterized in that the cylinder can move and can perform external work through movement, and the way in which the heat engine outputs mechanical energy includes performing external work through the movement of the cylinder. A heat engine is characterized in that it comprises a cylinder, wherein the cylinder comprises a working gas, and the working cycle of the working gas comprises a Carnot cycle. A heat pump having the same structure as the heat engine described in claim 5 and/or 7 and/or 8. A method for converting internal energy into mechanical energy through a cylinder, comprising a forward or reverse cycle of the following four steps: 1) Isothermal expansion of the working gas in the cylinder; 2) Adiabatic expansion of the working gas in the cylinder; 3) isothermal compression of the working gas in the cylinder; 4) Adiabatic compression of the working gas in the cylinder; The cylinder is a cylinder of any heat engine or heat pump described in claims 5-9. An internal combustion engine is characterized in that it includes a cylinder, and the working process of the internal combustion engine includes burning fuel in the cylinder to perform external work, and the combustion includes a reversible chemical reaction.