ES2729277T3 - Fluid machine - Google Patents

Abstract

Fluid machine with a working fluid, an evaporator (10), in which the working fluid can be transformed from its liquid state to its gaseous state with the heat input, a substantially adiabatic expansion tank (6), at less a piston machine (84, 85) with a piston (14, 15), by means of which energy from the working fluid can be converted into mechanical energy and having at least one cylinder chamber (37, 39) delimited by the piston (14, 15), which during the operation of the fluid machine (1) is connected in fluid communication, alternatively, with the evaporator (10), whereby the cylinder chamber (37, 39) is made larger by the displacement of the piston (14, 15), and with the expansion tank (6), whereby the cylinder chamber (37, 39) is made smaller by the displacement of the piston (14, 15), a storage tank (9), which is connected in fluid communication with the evaporator (10) and with the expansion tank (6), and a conveyor (8), which is configured to transport the working fluid, both in its gaseous state and in its liquid state, from the expansion tank (6) to the storage tank ( 9), where the volume available for the working fluid in the expansion tank (6) is at least 7 times the maximum volume of the first cylinder chamber (37, 39), so that the working fluid can condense by the expansion of the gaseous working fluid in the expansion tank (6), and in the storage tank (7) the working fluid is present both in its gaseous state and in its liquid state, so that the working fluid , in the event that it does not condense in the expansion tank, it can condense in the storage tank (9), and the working fluid can be transported in its liquid state to the evaporator (10).

Description

DESCRIPTION

Fluid machine

[0001] The invention relates to a fluid machine.

[0002] Conventionally, heat is converted into mechanical work in a fluid machine, such as, for example, in a thermoelectric plant. Mechanical work can be used, for example, to generate electricity or to compress a process gas. For the operation of the thermoelectric power plant, conventional fossil energy sources, such as coal, are burned, for example. It would be desirable to use alternative energy sources in this regard to avoid carbon dioxide emissions.

[0003] In the thermoelectric plant, water is evaporated in a cyclic process with the heat input and then condensed again with the removal of heat. The condensation of the water takes place, for example, in a cooling tower, in which an evaporation of the cooling water takes place and, therefore, the enthalpy of evaporation of the cooling water is used to extract the heat. Alternatively, natural bodies of water, for example, a river or a lake, can be used to remove heat. However, the elimination of heat is complex and also reduces the efficiency of the cyclic process, because the heat removed cannot be converted into mechanical energy.

[0004] Document DE 3327838 A1 discloses a steam engine cycle for the complete conversion of heat into mechanical work. US 2010/0252028 A1 discloses an intermediate pressure storage system as a thermal accumulator.

[0005] The aim of the invention is therefore to create an improved fluid machine that has high efficiency.

[0006] The objective is achieved with the features of claim 1. Preferred configurations thereof are indicated in the additional claims.

[0007] The fluid machine according to the invention has a working fluid, an evaporator, in which the working fluid can be transformed from its liquid state to its gaseous state with the heat input, a substantially expansion tank adiabatic, at least one piston machine with a piston, by means of which energy from the working fluid can be converted into mechanical energy and having at least one cylinder chamber delimited by the piston, which during the operation of the fluid machine it is connected in fluid communication, alternatively, with the evaporator, whereby the cylinder chamber is made larger by the displacement of the piston, and with the expansion tank, whereby the cylinder chamber is made smaller by the displacement of the piston, a storage tank, which is connected in fluid communication with the evaporator and with the expansion tank, and a conveyor, which is configured to transport the working fluid, both in its gaseous state and in its liquid state, from the expansion tank to the storage tank, where the expansion tank is sized in comparison to the cylinder chamber such that the working fluid can be condensed by the expansion of the gaseous fluid in the expansion tank, and in the storage tank the working fluid is present both in its gaseous state and in its liquid state, so that the working fluid, in the If it does not condense in the expansion tank, it can condense in the storage tank, and the working fluid can be transported in its liquid state to the evaporator.

[0008] The invention is based on the finding that if the expansion tank is sized large enough compared to the maximum size of the cylinder chamber, condensation of the working fluid can be produced only by the cold that occurs as result of its expansion by the Joule-Thomson effect. Therefore, advantageously, it is not necessary to provide for a heat removal from the fluid machine, whereby the fluid machine improves and the efficiency of the fluid machine is high. Because the expansion tank is large compared to the cylinder chamber, the working fluid also exerts a large tensile force on the piston during its expansion from the cylinder chamber to the expansion tank, so that the efficiency of the fluid machine is further increased. As the expansion tank is essentially adiabatic, it is advantageously prevented that ambient heat can cause the re-evaporation of condensed working fluid in the expansion tank or that heat can escape from the expansion tank. In case the condensation of the working fluid does not take place or only partially in the expansion tank, for example if, at the beginning of the operation of the fluid machine, the walls of the expansion tank have a temperature higher than the temperature of evaporation of the working fluid, the conveyor equipment is provided, which can transport the working fluid both gaseous and liquid, and the storage tank, which presents the working fluid both liquid and gaseous, to condense the working fluid. The conveyor equipment also causes an increase in the pressure of the working fluid from the expansion tank to the storage tank.

[0009] By having a storage tank, it is also not necessary for the conveyor to continuously transport the working fluid during the operation of the fluid machine. For example, the machine fluid can be configured in such a way that the conveyor equipment transports the working fluid only when a level of liquid working fluid is exceeded in the expansion tank and / or when a level of liquid working fluid is not reached in the storage tank storage. Because the transport equipment does not have to continuously transport the working fluid, the service life of the transport equipment is advantageously long and its energy consumption is low, so that the efficiency of the fluid machine is high.

[0010] It is preferable that the plunger machine has a first position sensor, which is configured to detect a first end position of the plunger, and a second position sensor, which is configured to detect a second end position of the plunger, where The fluid machine is configured to connect, when the first final position is reached, the first cylinder chamber in fluid communication with the evaporator and connect it, when the second final position is reached, in fluid communication with the expansion tank. In addition, the fluid machine is configured in such a way that, during the operation of the fluid machine, at the same time, when the first final position is reached, the fluid communication connection of the first cylinder chamber with the container of fluid is interrupted. expansion and upon reaching the second final position the connection in fluid communication of the first cylinder chamber with the evaporator is interrupted. In the first final position, the first cylinder chamber has its minimum size and, in the second final position, the first cylinder chamber has its maximum size.

[0011] It is preferable that the piston machine has a second cylinder chamber delimited by the piston, which during the operation of the fluid machine is connected in fluid communication with the evaporator, when the first cylinder chamber is connected in communication of fluid with the expansion tank, and is connected in fluid communication with the expansion tank, when the first cylinder chamber is connected in fluid communication with the evaporator. In addition, the fluid machine is configured such that, during operation, the connection in fluid communication of the respective cylinder chamber with the expansion vessel is interrupted, when the respective cylinder chamber is connected in fluid communication with the evaporator, and the connection in fluid communication of the respective cylinder chamber with the evaporator is interrupted, when the respective cylinder chamber is connected in fluid communication with the expansion vessel. Because the piston machine has two cylinder chambers, which are mutually connected to the evaporator and to the expansion vessel, it is possible, advantageously, a power of the piston machine greater than when it has only one cylinder chamber. Furthermore, it is advantageously possible, because of this, a continuous operation of the fluid machine, in particular the evaporator. In addition, the particularly large tensile force acts on the piston at the same time due to the expansion in the expansion tank and the compression force due to the flow of the working fluid from the evaporator.

[0012] It is preferable that the plunger machine has a first position sensor, which is configured to detect a first end position of the plunger, and a second position sensor, which is configured to detect a second end position of the plunger, where The fluid machine is configured to connect, when the first final position is reached, the first cylinder chamber in fluid communication with the evaporator and the second cylinder chamber in fluid communication with the expansion tank and to connect, upon reaching the second final position, the first cylinder chamber in fluid communication with the expansion tank and the second cylinder chamber in fluid communication with the evaporator.

[0013] The fluid machine preferably has two of the piston machines and is configured to operate the piston cycle of the second piston machine substantially offset one quarter of the piston cycle period with respect to the piston cycle of the first piston machine When one of the cylinder chambers is connected in fluid communication with the expansion tank, a substantially exponential decrease with the time of the mass flow of the working fluid from the cylinder chamber to the expansion tank is obtained. In this respect, the mass flow is the maximum at the beginning of the fluid communication connection. Due to the outdated operation of the two piston cycles, it is advantageously prevented that the maximum mass flow from the two piston machines does not occur at the same time. Because of this, the expansion tank is not requested at the same time with the maximum mass flow, so the expansion of the working fluid is associated with a large pressure drop and, therefore, advantageously, the efficiency of the machine of fluid is high. Another advantage is that, when one of the final positions of one of the two piston machines is reached, a mass flow of the working fluid in the fluid machine is maintained by the other of the two piston machines, whereby continuous operation of the fluid machine.

[0014] It is preferable that the evaporator is configured to operate in a temperature range to evaporate the working fluid, wherein the temperature range ranges from a temperature T1, which corresponds to the evaporation temperature of the working fluid, up to a temperature T1 + 10 ° C, in particular up to a temperature T1 + 5 0C. This prevents overheating of the working fluid in its gaseous state, which makes the probability that the working fluid is condensed solely by its expansion in the expansion vessel is high. Thus, the proportion of working fluid that must be condensed by the conveyor is low, so the efficiency of the fluid machine is high.

[0015] It is preferable that the fluid machine has a cold exchanger, by means of which it can Heat is transferred to the working fluid downstream of the expansion tank and upstream of the storage tank. Because of this, the conveyor consumes less energy, so the efficiency of the fluid machine is high. In addition, the fluid machine, in addition to mechanical energy, can also generate cold that can be used. Preferably, in this case a temperature regulation is provided, which regulates the heat input to the working fluid such that the working fluid in the cold exchanger has a temperature lower than the evaporating temperature of the working fluid, of so that there is no evaporation of the liquid working fluid. For this purpose, for example, a pressure gauge of the cold exchanger which measures the pressure of the working fluid in the cold exchanger can be provided. From the pressure of the working fluid its evaporation temperature can be determined.

[0016] Preferably, the evaporator has a hollow space and a nozzle, by means of which the liquid working fluid can be sprayed into the cavity. As a result, boiling delays cannot advantageously occur during evaporation of the working fluid, so that a uniform operation of the fluid machine is ensured. In addition, rapid evaporation of the working fluid can advantageously occur. Rapid evaporation can be further accelerated if the orientation of the nozzle and the opening angle of the working fluid exiting the nozzle are selected such that a possible large proportion of the working fluid reaches an evaporator wall, through from which the heat reaches the evaporator to evaporate the working fluid.

[0017] It is preferable that the fluid machine has a pressure sensor, configured to measure the pressure of the working fluid downstream of the evaporator and upstream of the plunger machine, and a regulating valve, configured to regulate the mass flow of the working fluid entering the evaporator so that the pressure measured by the pressure sensor is in a theoretical pressure range. By increasing the theoretical pressure range, the mechanical work to be emitted by the plunger machine can be increased, and by decreasing the theoretical pressure range, the mechanical work to be emitted by the plunger machine can be decreased. This constitutes a particularly simple regulation of the mechanical energy to be emitted by the fluid machine. For example, the regulating valve can be configured in such a way that the regulating valve has a variable opening degree for the working fluid and the mass flow is regulated with the opening degree. Alternatively, the regulating valve may be configured to alternate between an open position, in which the working fluid can pass through the regulating valve, and a closed position, in which the working fluid cannot pass through the control valve. regulation, and, during periods in the open position and the closed position, regulate the mass flow. Preferably, the upper end of the theoretical pressure range is less than 30 bar, especially preferably less than 20 bar. This makes it possible, for example, to use a fiber reinforced plastic for the plunger machine and / or the expansion tank, which is advantageously lighter than a metal. For example, if carbon dioxide is used for the working fluid, with the upper limit of 30 bar an evaporation of the working fluid can occur at a temperature of up to -5 0C, with an upper limit of 20 bar an evaporation can occur of working fluid up to -15 0C.

[0018] The evaporator is preferably configured to operate in a temperature range chosen according to the theoretical pressure range to evaporate the working fluid, wherein the temperature range ranges from a temperature T1, which corresponds to the temperature of evaporation of the working fluid at the upper end of the theoretical pressure range, up to a temperature T1 + 10 0C, in particular up to a temperature T1 + 5 0C. This prevents overheating of the working fluid in its gaseous state, which makes the probability that the working fluid is condensed solely by its expansion in the expansion vessel is high. Thus, the proportion of working fluid that must be condensed by the conveyor is low, so the efficiency of the fluid machine is high.

[0019] It is preferable that the working fluid is carbon dioxide, propane, butane, R134a and / or C5F12. An evaporation of these working fluids can take place advantageously already at room temperature, even in winter at low temperatures below zero. This means that it is enough to remove heat from the environment to achieve evaporation of the working fluid. Because of this, it is advantageously not necessary to burn fossil energy sources for the operation of the fluid machine, which makes the fluid machine have a good CO2 balance. With the mechanical energy generated by the fluid machine, for example, a generator can be driven, which generates electrical energy, by means of which the conveyor equipment is then driven. In this case, the fluid machine would not emit any CO2 at all. Carbon dioxide is especially preferred. The carbon dioxide is advantageously non-toxic, non-flammable and also has particularly good thermodynamic properties for the fluid machine, such as, for example, a low evaporation enthalpy. The low enthalpy of evaporation advantageously leads to high efficiency of the fluid machine.

[0020] The volume available for the working fluid in the expansion tank, according to the invention, is at least 7 times the maximum volume of the first cylinder chamber. This advantageously ensures that the working fluid can condense due to its expansion. The volume available for the working fluid in the expansion tank is preferably at least 10 times the maximum volume of the first cylinder chamber.

[0021] It is preferable that the conveyor is a membrane pump and / or a plunger pump. The membrane pump is advantageously silent, easy to build and low maintenance cost. In this respect, the piston pump has a lower acquisition cost than the membrane pump.

[0022] It is preferable that the piston machine has a hydraulic cylinder with a hydraulic piston, which can be driven by the piston, wherein the hydraulic cylinder has a first hydraulic cylinder chamber limited by the hydraulic piston, which is filled with a additional working fluid, where, with the additional working fluid, a hydraulic motor can be driven and / or where the fluid machine has a heat pump and the additional working fluid is the working fluid of the heat pump , so that the hydraulic cylinder is a heat pump compressor, and / or where the additional working fluid is a process gas and the fluid machine is configured to compress the process gas for a process.

[0023] In the event that a hydraulic motor can be driven, the additional working fluid is any hydraulic fluid. The hydraulic fluid may have, for example, a mineral oil. It is conceivable that the hydraulic piston has a smaller cross section than the cross section of the piston, so that the additional working fluid has a higher pressure than the working fluid during the operation of the fluid machine. For example, the ratio of the cross sections can be selected so that an additional working fluid pressure of more than 100 bar can be generated. The fluid machine can present the hydraulic motor. The hydraulic motor can be used to replace gasoline engines and diesel engines. For example, a vehicle propulsion, a marine propulsion and / or a generator can be driven with the hydraulic motor. With the generator you can generate electricity. The generator may be electrically connected to an electrical network to supply power and / or be electrically connected to the conveyor to drive the conveyor. In case the fluid machine has two of the piston machines and is configured to operate the piston cycle of the second piston machine substantially offset one quarter of the piston cycle period with respect to the piston cycle of the first piston machine, a drop in the pressure of the hydraulic fluid is advantageously prevented when one of the end positions of the pistons is reached, because the pressure of the other respective hydraulic piston is maintained.

[0024] In case the hydraulic cylinder is the heat pump compressor, the additional working fluid can also be carbon dioxide, propane, butane, R134a and / or C5F12. The heat pump can be used to cool and / or to heat. In case the heat released by the heat pump is not completely used for heating, the fluid machine may be configured such that the heat released by the heat pump can be supplied at least partially to the evaporator. Due to this, the efficiency of the fluid machine is increased in its operation. Again, it is conceivable in this case that the hydraulic piston has a smaller cross section than that of the piston, so that an additional working fluid pressure greater than the working fluid pressure can be generated in the heat pump. For example, the ratio of the cross sections can be selected so that an additional working fluid pressure of more than 50 bar can be generated.

[0025] In case the additional working fluid is a process gas, the process gas can be, for example, air, which is compressible by means of the fluid machine giving rise to compressed air. The fluid machine may be configured such that the heat released during compression is at least partially supplied to the evaporator.

[0026] It is preferable that the hydraulic motor has an inlet and an outlet for the additional working fluid and that the hydraulic cylinder has a second hydraulic cylinder delimited by the hydraulic piston. wherein the fluid machine is configured, in order to drive the hydraulic motor, to connect the first hydraulic cylinder chamber in fluid communication alternately with the inlet and the outlet and to connect the second hydraulic cylinder chamber in communication of fluid with the outlet, when the first hydraulic cylinder chamber is connected to the inlet, as well as connect it in fluid communication with the inlet, when the first hydraulic cylinder chamber is connected to the outlet. As a result, greater power can be advantageously achieved with the hydraulic cylinder than in the case of a hydraulic cylinder having a single hydraulic cylinder chamber.

[0027] The piston and hydraulic piston preferably have a common piston rod. Because of this, a compact construction of the piston machine is advantageously achieved.

[0028] Next, two preferred embodiments of the fluid machine according to the invention will be explained with reference to the accompanying schematic drawings. They show:

Figure 1 a first embodiment and

Figure 2 a second embodiment.

[0029] As can be seen from Figures 1 and 2, a fluid machine 1 according to the first and second embodiments has a fluid circuit 3, through which a working fluid can circulate. The working fluid can be carbon dioxide, propane, butane, R134a and / or C5F12.

[0030] The fluid circuit 3 has an evaporator 10, in which the working fluid can be transformed from its liquid state to its gaseous state with the heat input. In addition, the fluid circuit 3 has a substantially adiabatic expansion tank 6. In addition, the fluid circuit 3 has a first piston machine 84 with a first plunger 14 and a second plunger machine 85 with a second plunger 15, wherein the first plunger machine 84 and the second plunger machine 85 are substantially identical in construction.

[0031] The first piston machine 84 has a first cylinder chamber 37 delimited by the plunger 14 and a second cylinder chamber 38 delimited by the plunger 14. The second piston machine 85 has a first cylinder chamber 39 delimited by the piston 15 and a second cylinder chamber 40 delimited by piston 15. Each of the cylinder chambers 37 to 40 is connected, during operation of the fluid machine 1, alternatively in fluid communication with the evaporator 10, so that the respective cylinder chambers 37 to 40 are made larger by the displacement of the associated pistons 14, 15, and with the expansion tank 6, whereby the respective cylinder chambers 37 to 40 are made smaller by the displacement of the associated plungers 14, 15. The second cylinder chambers 38, 40 are connected, during operation of the fluid machine 1, in fluid communication with the evaporator 10, when the first cylinder chambers 37, 39 belonging to the same piston machine 84, 85 are connected in fluid communication with the expansion tank 6, and are connected in fluid communication with the expansion tank 6, when the first cylinder chambers 37, 39 belonging to the same piston machine 84, 85 are connected in communication of fluid with evaporator 10.

[0032] The fluid circuit 3 has a storage tank 9, which is connected in fluid communication with the evaporator 10 and with the expansion tank 6. In addition, the fluid circuit 3 has a conveyor 8, which is configured for transporting the working fluid, both in its gaseous state and in its liquid state, from the expansion tank 6 to the storage tank 9. The conveyor equipment 8 can be, for example, a membrane pump and / or a pump piston

[0033] The expansion tank 6 is sized in comparison with the cylinder chambers 37, 39 such that the working fluid can be condensed by the expansion of the gaseous fluid in the expansion tank 6. For this purpose, the available volume for the working fluid in the expansion tank 6 it is at least 7 times, in particular at least 10 times, the maximum volume of the first cylinder chamber 37 of the first piston machine 84 or the first cylinder chamber 39 of the second plunger machine 85.

[0034] In the storage tank 7, the working fluid is present both in its gaseous state and in its liquid state, so that the working fluid, in the event that it does not condense in the expansion tank 6, it can be condensed in the storage tank 9 and, in particular, when transported by the conveyor 8 to the storage tank 9. The working fluid can be transported in its liquid state from the storage tank 9 to the evaporator 10.

[0035] The first plunger machine 84 has a first position sensor 57, which is configured to detect a first end position of the plunger 14, and a second position sensor 58, which is configured to detect a second end position of the plunger 14 The second piston machine 85 has a first position sensor 59, which is configured to detect a first end position of the piston 15, and a second position sensor 60, which is configured to detect a second final position of the piston 15. The fluid machine 1 is configured to connect, when the first final position is reached, the corresponding first cylinder chambers 37, 39 in fluid communication with the evaporator 10 and the corresponding second cylinder chambers 38, 40 in fluid communication with the tank expansion 6 and to connect, when the second final position is reached, the first cylinder chambers 37, 39 corresponding in com fluid connection with the expansion tank 6 and the corresponding second cylinder chambers 38, 40 in fluid communication with the evaporator 10.

[0036] For this purpose, the fluid machine 1 has a first fluid switching element 35 for the first piston machine 84 and a second fluid switching element 36 for the second piston machine 85. The fluid machine 1 it has a first fluid cylinder conduit 68, which connects in fluid communication the first chamber of the cylinder 37 of the first piston machine 84 with the first fluid switching element 35, and a second fluid cylinder conduit 69, which connects in fluid communication the second cylinder chamber 38 of the first piston machine 84 with the first fluid switching element 35. The fluid machine 1 has a first fluid cylinder conduit 70, which connects in fluid communication the first cylinder chamber 39 of the second piston machine 85 with the second fluid switching element 36, and a second fluid cylinder conduit 71, which connects in communication With the second cylinder chamber 40 of the second piston machine 85 with the second fluid switching element 36. The fluid machine 1 has a first fluid cylinder supply conduit 66, which connects the evaporator 10 in communication of fluid with the first fluid switching element 35, and a second fluid cylinder supply conduit 67, which connects the evaporator 10 in fluid communication with the second fluid switching element 36. To this end, the flow ducts Fluid cylinder supply 66, 67 are connected to a fluid distributor 33, which is connected via a conduit 65 in fluid communication with the evaporator 10. Finally, the fluid machine 1 has a first cylinder discharge conduit of fluid 72, which connects the first fluid switching element 35 in fluid communication with the expansion tank 6, and a second cylinder discharge duct of f luido 73, which connects the second fluid switching element 36 in fluid communication with the expansion tank 6.

[0037] The fluid machine 1 is configured to connect in fluid communication, by means of the first switching element 35, upon reaching the first end position of the piston 14, the first fluid cylinder conduit 68 with the first supply conduit of fluid cylinder 66 and the second fluid cylinder conduit 69 with the second fluid cylinder discharge conduit 72 and, upon reaching the second end position of the plunger 14, the first fluid cylinder conduit 68 with the first fluid conduit discharge of fluid cylinder 72 and the second fluid cylinder conduit 69 with the first fluid cylinder supply conduit 66. Similarly, the fluid machine 1 is configured to connect in fluid communication, by means of the second element of switching 36, upon reaching the first end position of the piston 15, the first fluid cylinder conduit 70 with the second fluid cylinder supply conduit 67 and the second fluid cylinder conduit 71 with the second fluid cylinder discharge conduit 73 and, upon reaching the second end position of the piston 15, the first fluid cylinder conduit 70 with the second discharge cylinder conduit of fluid 73 and the second fluid cylinder conduit 71 with the second fluid cylinder supply conduit 67.

[0038] The fluid machine 1 is configured to operate the piston cycle of the second piston machine 85 substantially offset one quarter of the piston cycle period with respect to the piston cycle of the first piston machine 84. The figures 1 and 2 show the case in which the second piston machine 85 advances to the first piston machine 1.

[0039] Figures 1 and 2 show that the fluid machine 1 has a cold exchanger 7, by means of which heat can be transferred to the working fluid downstream of the expansion tank 6 and upstream of the storage tank 9. With For this purpose, the fluid machine 1 has a conduit 61, which connects the expansion tank 6 in fluid communication with the cold exchanger 7. The conduit 61 can be connected to a riser located inside the expansion tank 6 or to the lower end of the expansion tank 6, in order to drive the working fluid in its liquid state to the cold exchanger 7. The conveyor equipment 8 is arranged downstream of the expansion tank 6 and upstream of the heat exchanger. cold 7. A check valve 111 is provided downstream of the conveyor 8 and upstream of the cold exchanger 7. A conduit 62 connects the conveyor 8 in communication of fluid with the storage vessel 9. The cold exchanger 7 has a cooling circuit 23 for circulating a cooling medium with an inlet line 24 of the refrigeration circuit and an outlet line 25 of the refrigeration circuit. During operation of the fluid machine 1, heat can be transferred from the cooling medium to the working fluid. The cooling medium may have, for example, water or, when the cooling medium must reach temperatures below 0 ° C, for example, salt water and / or antifreeze, such as ethanol. However, it is also conceivable not to have the cold exchanger 7 according to Figure 1, in order to increase the efficiency of the fluid machine 1.

[0040] The temperature of the cooling medium can be adjusted by means of a controller such that evaporation of the working fluid in the cold exchanger does not take place 7. For this purpose, for example, a flow meter can be provided. cold exchanger pressure, configured to measure the working fluid pressure in the cold exchanger. From the pressure of the working fluid its evaporation temperature can be determined, so that the temperature of the working fluid can be adjusted such that evaporation of the working fluid in the cold exchanger 7 does not occur.

[0041] In the storage tank 9, the working fluid is present both in its gaseous state and in its liquid state, so that in the upper part of the storage tank 9 there is a gaseous phase 27 of the working fluid and in the lower part of the storage tank 9 is a liquid phase 28 of the working fluid. In order to transport the working fluid in its liquid state to the cold exchanger 10, the storage tank 9 has a riser tube 26, the lower end of which is submerged in the liquid phase 28. By means of a conduit 64, the evaporator 10 is connected in fluid communication with the riser tube 26. As an alternative to the riser tube 26 and the conduit 64, a conduit may be provided at the lower end of the storage tank 9, which connects the storage tank 9 in fluid communication with the evaporator 10. By connecting the duct 64, a connection to the filling station 29 is provided, through which the working fluid can be introduced into the fluid circuit 3. The connection to the filling station 29 has a shut-off valve 97, by means of which the fluid circuit 3 can be opened to introduce the working fluid.

[0042] As can be seen from Figures 1 and 2, the evaporator 10 has a hollow space 86 and a nozzle 11, by means of which the liquid working fluid can be sprayed into the cavity 86. The nozzle 11 can be be, for example, the nozzle of an oil burner. The nozzle can work, for example, at up to 20 bar. The hollow space 86 is substantially in the form of a cylinder, wherein the nozzle 11 is disposed on the axis of the cylinder and oriented in its direction. The nozzle 11 may be configured to spray the working fluid substantially in the form of a conical envelope, the axis of the conical envelope and the axis of the cylinder being coincident. The opening angle of the conical envelope can be, for example, 50 ° to 80 °, whereby the working fluid strikes the inner wall of the cylinder and can therefore evaporate rapidly.

[0043] The evaporator 10 has a heating circuit 51 for circulating a heating means having an input line 52 of the heating circuit and an output line 53 of the heating circuit. Through the heating circuit 51, heat can be supplied to evaporate the working fluid to the evaporator 10 and, in particular, is transferred from the heating medium to the working fluid. If carbon dioxide is used for the working fluid, the heating circuit 51 can be connected to any heat source up to a minimum temperature of -20 ° C. For example, the environment, the residual heat of a machine and / or process heat can be used as a heat source. The heating circuit 51 may be connected, for example, to a solar thermal energy system or an air conditioner, which provides the heat necessary for evaporation. The heating medium may be, for example, water.

[0044] The fluid machine 1 has a pressure sensor 32, configured to measure a working fluid pressure downstream of the evaporator 10 and upstream of the plunger machine 84, 85, and a regulating valve 31, configured to regulate the mass flow of the working fluid entering the evaporator 10 such that the pressure measured by the pressure sensor 32 is in a theoretical pressure range. According to Figures 1 and 2, the pressure sensor 32 is configured to measure the pressure in the duct 65. The evaporator 10 is configured to operate in a temperature range chosen according to the theoretical pressure range to evaporate the fluid from work, where the temperature range ranges from a temperature T1, which corresponds to the evaporation temperature of the working fluid at the upper end of the theoretical pressure range, up to a temperature T1 + 10 0C, in particular up to a temperature T1 + 5 ° C

[0045] As can be seen from Figure 1, the first embodiment presents a hydraulic circuit 5, configured to use the mechanical energy released by the piston machines 84, 85 by circulating a hydraulic fluid to drive an engine. hydraulic 20. According to figure 1, the fluid machine 1 has a fluid side 2, which has the hydraulic circuit 3 and in which the mechanical energy is generated. In addition, the fluid machine 1 has a hydraulic side 4, which has the hydraulic circuit 5 and in which the mechanical energy is used to drive the hydraulic motor 20.

[0046] The first piston machine 84 has a first fluid cylinder 12, in which the first piston 14 is movably mounted, and a first hydraulic cylinder 16, in which a first hydraulic piston 18 is movably mounted. . The first piston 14 and the first hydraulic piston 18 have a first common piston rod 89, so that the first hydraulic piston 18 can be driven by the first piston 14. The first piston machine 84 has a first separation wall 126 between the first fluid cylinder 12 and the first hydraulic cylinder 16. The first separation wall 126 has a hole, through which the first piston rod 89 is guided. Similarly, the second piston machine 85 has a second cylinder of fluid 13, in which the second piston 15 is movably mounted, and a second hydraulic cylinder 17, in which a second hydraulic piston 19 is movably mounted. The second piston 15 and the second hydraulic piston 19 have a second common piston rod 90, so that the second hydraulic piston 19 can be driven by the second piston 15. The second piston machine 85 has a second separation wall 127 between the second fluid cylinder 13 and the second hydraulic cylinder 17. The second separation wall 127 has a hole, through which the second piston rod 90 is guided. The first and the second hydraulic piston 18, 19 have a cross section. smaller than the cross section of the first and second fluid plunger 14, 15, so that a higher pressure can be generated in the hydraulic circuit 5 than in the fluid circuit 3. For example, the ratio of the cross sections It can be selected in such a way that a pressure of more than 120 bar can be generated in the fluid circuit 5.

[0047] The first hydraulic cylinder 16 has a first hydraulic cylinder chamber 41 and a second hydraulic cylinder chamber 42, defined in each case by the first hydraulic piston 18. Similarly, the second hydraulic cylinder 17 has a first chamber of hydraulic cylinder 43 and a second hydraulic cylinder chamber 44, delimited in each case by the second hydraulic piston 19.

[0048] To drive the hydraulic motor 20, it has an inlet 87 and an outlet 88 for the hydraulic fluid. The fluid machine 1 is configured, in order to drive the hydraulic motor 20, to connect in fluid communication the first two hydraulic cylinder chambers 41, 43 alternately with the inlet 87 and with the outlet 88 and to connect in the communication of the two second hydraulic cylinder chambers 42, 44 with the outlet 88 fluid, when the first two hydraulic cylinder chambers 41.43 are connected to the inlet 87, as well as connect it in fluid communication with the inlet 87, when the first two 41.43 hydraulic cylinder chambers are connected to outlet 88.

[0049] To this end, the fluid machine 1 has a first hydraulic switching element 45 for the first piston machine 84 and a second hydraulic switching element 46 for the second piston machine 85. The fluid machine 1 has a first hydraulic cylinder conduit 74, which connects in fluid communication the first hydraulic cylinder chamber 41 of the first piston machine 84 with the first hydraulic switching element 45, and a second hydraulic cylinder conduit 75, which connects in communication of the second hydraulic cylinder chamber 42 of the first piston machine 84 with the first hydraulic switching element 45 is fluid. The fluid machine 1 has a first hydraulic cylinder duct 76, which connects the first cylinder chamber 43 in fluid communication of the second piston machine 85 with the second hydraulic switching element 46, and a second cylinder line hydraulic 77, which connects in fluid communication the second hydraulic cylinder chamber 44 of the second piston machine 85 with the second hydraulic switching element 46. The fluid machine 1 has a first hydraulic cylinder supply conduit 78, which connects the outlet 88 in fluid communication with the first hydraulic switching element 45, and a second hydraulic cylinder supply conduit 79, which connects the outlet 88 in fluid communication with the second element of hydraulic switching 46. To this end, the hydraulic cylinder supply lines 78, 79 are connected to a first hydraulic distributor 55, which is connected by means of a motor discharge conduit 83 in fluid communication with the outlet 88. Finally, the fluid machine 1 has a first hydraulic cylinder discharge duct 80, which connects the first hydraulic switching element 45 in fluid communication with the inlet 87, and a second hydraulic cylinder discharge duct 81, which connects the second hydraulic switching element 46 in fluid communication with the inlet 87. For this purpose, the discharge ducts d The hydraulic cylinder 80, 81 is connected to a first hydraulic distributor 56, which is connected by means of a motor supply conduit 82 in fluid communication with the inlet 87.

[0050] The fluid machine 1 is configured to connect in fluid communication, by means of the first hydraulic switching element 45, upon reaching the first end position of the piston 14, the first hydraulic cylinder conduit 74 with the first supply conduit of hydraulic cylinder 78 and the second hydraulic cylinder conduit 75 with the second hydraulic cylinder discharge conduit 80 and, upon reaching the second final position of the piston 14, the first hydraulic cylinder conduit 74 with the first hydraulic cylinder discharge conduit 80 and the second hydraulic cylinder conduit 75 with the first hydraulic cylinder supply conduit 78. Similarly, the fluid machine 1 is configured to connect in fluid communication, by means of the second hydraulic switching element 46, upon reaching the first final position of the plunger 15, the first hydraulic cylinder duct 76 with the second c hydraulic cylinder supply line 79 and the second hydraulic cylinder duct 77 with the second hydraulic cylinder discharge duct 81 and, upon reaching the second end position of the piston 15, the first hydraulic cylinder duct 76 with the second discharge duct of hydraulic cylinder 81 and the second hydraulic cylinder conduit 77 with the second hydraulic cylinder supply conduit 79.

[0051] The fluid machine 1 has a hydraulic regulating valve 54 in the motor supply line 82, by means of which the power that can be emitted by the hydraulic motor 20 can be adjusted. For example, the power adjustment can be be carried out through an opening degree for the hydraulic liquid that has to pass through a hydraulic regulating valve 54. In addition, the hydraulic regulating valve 54 causes the hydraulic motor 20 to be requested at a constant pressure for an established power.

[0052] By deploying and refolding the hydraulic pistons 18, 19 a different pressure is generated in the hydraulic circuit 4, because, due to the two piston rods 89, 90, the active surface of the hydraulic pistons 18, 19 is different. Therefore, the hydraulic circuit 4 has a hydraulic accumulator 22, for example, a membrane accumulator and / or a piston accumulator, with which the pressure during deployment and withdrawal remains constant. The hydraulic accumulator 22 is connected in fluid communication with the second hydraulic distributor 56.

[0053] As can be seen from Figure 1, the fluid machine 1 has a transmission 48 and a generator 21, which can be driven by the hydraulic motor 20 through the transmission 48 to generate electric current. It is conceivable to electrically connect the conveyor 8 to the generator 21, to drive the conveyor 8 with the generator 21.

[0054] In addition, the fluid machine 1 has several shut-off valves 91 to 96 and 98 to 108 at various points, with which the individual components of the fluid machine 1 can be isolated for maintenance purposes. In addition, the fluid machine 1 has check points 109 to 114 at various points, which prevent an inversion of the flow of the working fluid. The fluid machine 1 has a first pressure gauge 30, by means of which the working fluid pressure can be measured downstream of the storage tank 9 and upstream of the evaporator 10, and a second pressure gauge 34, by means of from which the pressure of the working fluid can be measured downstream of the evaporator 10 and upstream of the two piston machines 84, 85. In addition, the fluid machine 1 has a first hydraulic pressure gauge 49, by means of which it can measure the pressure downstream of the two piston machines 84, 85 and upstream of the inlet 87, and a second hydraulic pressure gauge 50, by means of which the pressure downstream of the outlet 88 and upstream can be measured of the two piston machines 84, 85.

[0055] As can be seen from Figure 2, the second embodiment differs from the first embodiment in that no cold exchanger 7 is provided and in that the fluid machine 1 has a heat pump 128 with An additional working fluid. The additional working fluid is, for example, carbon dioxide, propane, butane, R134a and / or C5F12. The heat pump features a condenser 115, in which the additional working fluid can be condensed with the evacuation of heat by means of an additional cooling circuit 130, a butterfly 116, and an evaporator 117, in which the fluid of Additional work can be evaporated with the heat input by means of an additional heating circuit 129. The hydraulic cylinder 17 is configured to transport the working fluid from the evaporator 117 to the condenser 115. The evaporator 117 is connected in fluid communication with the butterfly 116 and the butterfly is connected in fluid communication with the evaporator 121. Through a shut-off valve 120, the additional working fluid can be introduced into the pump of heat For example, the ratio of the cross section of the second hydraulic piston 19 with respect to the second fluid piston 15 can be selected such that a pressure of more than 50 bar can be generated in the heat pump circuit 128.

[0056] The heat pump 128 may have shut-off valves 118 to 122, to isolate the individual components of the heat pump 128. The heat pump 128 has a third pressure gauge 128, configured to measure the fluid pressure of working downstream of condenser 115 and upstream of throttle 116, and a fourth pressure gauge 125, configured to measure the pressure of the working fluid downstream of throttle 116 and upstream of evaporator 117. With the third and fourth Pressure gauge 124, 125 can measure the pressure drop across the throttle.

[0057] The fluid machine 1 also has a first closing element 131, for example, a magnetic valve, in the first fluid cylinder supply conduit 66 and a second closing element 132, for example, a valve magnetic, in the second fluid cylinder supply duct 67. Therefore, the hydraulic circuit 5 and the heat pump 128 can be switched on and off independently of each other.

Reference List

[0058]

1 fluid machine

2 fluid side

3 fluid circuit

4 hydraulic side

5 hydraulic circuit

6 expansion tank

7 cold exchanger

8 conveyor equipment

9 storage tank

10 evaporator

11 nozzle

12 first fluid cylinder

13 second fluid cylinder

14 first plunger

15 second plunger

16 first hydraulic cylinder

17 second hydraulic cylinder

18 first hydraulic piston

19 second hydraulic piston

20 hydraulic motor

21 generator

22 hydraulic accumulator

23 cooling circuit

24 refrigeration circuit input line

25 refrigeration circuit output line

26 riser

27 gas phase

28 liquid phase

29 connection to the filling station

30 first pressure gauge

31 regulating valve

32 pressure sensor

33 fluid distributor

34 second pressure gauge

35 first fluid switching element

36 second fluid switching element

37 first cylinder chamber

38 second cylinder chamber

39 first cylinder chamber

40 second cylinder chamber

41 first hydraulic cylinder chamber

42 second hydraulic cylinder chamber

43 first hydraulic cylinder chamber

44 second hydraulic cylinder chamber

45 first hydraulic switching element

46 second hydraulic switching element

transmission

first hydraulic pressure gauge

second pressure gauge hydraulic pressure heating circuit

heating circuit input line

heating circuit output line hydraulic regulating valve

first hydraulic distributor

second hydraulic distributor

first position sensor

second position sensor

first position sensor

second position sensor

conduit

conduit

conduit

conduit

conduit

first fluid cylinder supply conduit second fluid cylinder supply conduit first fluid cylinder conduit

second fluid cylinder duct

first fluid cylinder duct

second fluid cylinder duct

first fluid cylinder discharge conduit second fluid cylinder discharge conduit first hydraulic cylinder conduit

second hydraulic cylinder duct

first hydraulic cylinder duct

second hydraulic cylinder duct

first hydraulic cylinder supply conduit second hydraulic cylinder supply conduit first hydraulic cylinder discharge conduit second hydraulic cylinder discharge conduit motor supply conduit

motor discharge duct

first plunger machine

second piston machine

hollow space

entry

exit

first piston rod

second piston rod

Closing valve

Closing valve

Closing valve

Closing valve

Closing valve

Closing valve

Closing valve

Closing valve

Closing valve

Closing valve

Closing valve

Closing valve

Closing valve

Closing valve

Closing valve

Closing valve

Closing valve

Closing valve

retention valve

retention valve

retention valve

retention valve

retention valve

condenser check valve

butterfly

evaporator

Closing valve

Closing valve

Closing valve

Closing valve

Closing valve

retention valve

third pressure gauge fourth pressure gauge first separation wall second separation wall heat pump

additional heating circuit additional cooling circuit first closing element second closing element

Claims (15)

1. Fluid machine with a working fluid, an evaporator (10), in which the working fluid can be transformed from its liquid state to its gaseous state with the heat input, a substantially adiabatic expansion tank (6) , at least one piston machine (84, 85) with a piston (14, 15), by means of which energy from the working fluid can be converted into mechanical energy and having at least one cylinder chamber (37, 39) delimited by the piston (14, 15), which during operation of the fluid machine (1) is connected in fluid communication, alternatively, with the evaporator (10), so that the cylinder chamber (37, 39) it becomes larger by the displacement of the piston (14, 15), and with the expansion tank (6), whereby the cylinder chamber (37, 39) is made smaller by the displacement of the piston (14, 15 ), a storage tank (9), which is connected in fluid communication with the evaporator (10) and with the expansion tank (6), and a conveyor (8), which is configured to transport the working fluid, both in its gaseous state and in its liquid state, from the expansion tank (6) to the storage tank (9), wherein the volume available for the working fluid in the expansion tank (6) is at least 7 times the maximum volume of the first cylinder chamber (37, 39), so that the working fluid can condense by the expansion of the gaseous working fluid in the expansion tank (6), and in the storage tank (7) the working fluid is present both in its gaseous state and in its liquid state, so that the fluid of work, in the event that it does not condense in the expansion tank, it can condense in the storage tank (9), and the working fluid can be transported in its liquid state to the evaporator (10). 2. Fluid machine according to claim 1, wherein the plunger machine (84, 85) has a first position sensor (57, 59), which is configured to detect a first end position of the plunger (14, 15 ), and a second position sensor (58, 60), which is configured to detect a second end position of the plunger (14, 15), where the fluid machine (1) is configured to connect, upon reaching the first position Finally, the first cylinder chamber (37, 39) in fluid communication with the evaporator (10) and connect it, when the second final position is reached, in fluid communication with the expansion tank (6). 3. Fluid machine according to claim 1 or 2, wherein the plunger machine (84, 85) has a second cylinder chamber (38, 40) delimited by the plunger (14, 15), which, during the operation of the fluid machine (1), is connected in fluid communication with the evaporator (10), when the first cylinder chamber (37, 39) is connected in fluid communication with the expansion tank (6), and it is connected in fluid communication with the expansion tank (6), when the first cylinder chamber (37, 39) is connected in fluid communication with the evaporator (10). 4. Fluid machine according to claim 3, wherein the plunger machine (84, 85) has a first position sensor (57, 59), which is configured to detect a first end position of the plunger (14, 15 ), and a second position sensor (58, 60), which is configured to detect a second end position of the plunger (14, 15), where the fluid machine is configured to connect, upon reaching the first final position, the first cylinder chamber (37, 39) in fluid communication with the evaporator (10) and the second cylinder chamber (38, 40) in fluid communication with the expansion tank (6) and to connect, upon reaching the second final position, the first cylinder chamber (37, 39) in fluid communication with the expansion tank (6) and the second cylinder chamber (38, 40) in fluid communication with the evaporator (10). 5. Fluid machine according to claim 3 or 4, wherein the fluid machine (1) has two of the piston machines (84, 85) and is configured to operate the piston cycle of the second machine piston (85) substantially offset one quarter of the period of the piston cycle with respect to the piston cycle of the first piston machine (84). 6. Fluid machine according to one of claims 1 to 5, wherein the evaporator (10) is configured to operate in a temperature range to evaporate the working fluid, wherein the temperature range ranges from a temperature T1 , which corresponds to the evaporation temperature of the working fluid, up to a temperature T1 + 10 0C, in particular up to a temperature T1 + 5 0C. 7. Fluid machine according to one of claims 1 to 6, wherein the evaporator (10) has a hollow space (86) and a nozzle (11), by means of which the liquid working fluid can be sprayed to the cavity (86). 8. Fluid machine according to one of claims 1 to 7, wherein the fluid machine (1) has a pressure sensor (32), configured to measure a working fluid pressure downstream of the evaporator (10) and upstream of the plunger machine (84, 85), and a regulating valve (31), configured to regulate the mass flow of the working fluid entering the evaporator (10) such that the pressure measured by the Pressure sensor (32) is located in a target pressure range. 9. Fluid machine according to claim 8, wherein the evaporator (10) is configured to operate in a temperature range chosen according to the theoretical pressure range to evaporate the working fluid, wherein the temperature range is of a temperature T1, which corresponds to the evaporation temperature of the working fluid at the upper end of the theoretical pressure range, up to a temperature Ti 10 0C, in particular up to a temperature T1 + 5 0C. 10. Fluid machine according to one of claims 1 to 9, wherein the working fluid is carbon dioxide, propane, butane, R134a and / or C5F12. 11. Fluid machine according to one of claims 1 to 10, wherein the volume available for the working fluid in the expansion tank (6) is at least 10 times the maximum volume of the first cylinder chamber (37 , 39). 12. Fluid machine according to one of claims 1 to 11, wherein the conveyor (9) is a membrane pump and / or a plunger pump. 13. Fluid machine according to one of claims 1 to 12, wherein the plunger machine (84, 85) has a hydraulic cylinder (16, 17) with a hydraulic plunger (18, 19), which can be driven by the piston (14, 15), wherein the hydraulic cylinder (16, 17) has a first hydraulic cylinder chamber (41, 43) delimited by the hydraulic piston (18, 19), which is filled with a working fluid additional, where a hydraulic motor (20) can be driven with the additional working fluid and / or where the fluid machine has a heat pump (128) and the additional working fluid is the pump's working fluid of heat (128), whereby the hydraulic cylinder (16, 17) is a heat pump compressor (128), and / or where the additional working fluid is a process gas and the fluid machine ( 1) is configured to compress the process gas for a process. 14. Fluid machine according to claim 13, wherein the fluid machine (1) has the hydraulic motor (20), which has an inlet (87) and an outlet (88) for the additional working fluid, and the hydraulic cylinder (16, 17), which has a second hydraulic cylinder chamber (42, 44) delimited by the hydraulic piston (18, 19), where the fluid machine (1) is configured, in order to drive the hydraulic motor, to connect in fluid communication the first hydraulic cylinder chamber (41, 43) alternately with the inlet (87) and with the outlet (88) and to connect the second hydraulic cylinder chamber (42, 44) in fluid communication with the outlet (88), when the first hydraulic cylinder chamber (41, 43) is connected to the inlet (87), as well as connecting it in fluid communication with the inlet (87), when the first chamber of Hydraulic cylinder (41.43) is connected to the outlet (88). 15. A fluid machine according to claim 13 or 14, wherein the piston (14, 15) and the hydraulic piston (18, 19) have a common piston rod (89, 90).