RU226094U1 - Thermal block of a condensing boiler - Google Patents

Abstract

The utility model relates to the energy sector and can be used in boilers running on gas fuel to power central and individual heating circuits or to produce hot water. The purpose of the utility model is to create a design of a thermal unit that would have a technologically advanced and compact design for the creation of mass production of boilers. To solve this problem, a thermal unit is proposed, consisting of a heating water chamber and, pre-connected to it, a combustion chamber, as well as a heat exchanger having pipes through which the exhaust gases of the boiler furnace flow and which are surrounded on the outside by heating water, characterized in that the body consists of vertical cylindrical shells located coaxially, between which there is a coolant, and the inner shell is divided horizontally into two parts, the upper of which serves as a firebox, and the lower is a heating water chamber with a condensation heat exchanger consisting of a set of smoke pipes, or a round section with inserted turbulators, either oval cross-section, or rectangular cross-section with fins in the form of convex and/or concavities to increase both the cross-sectional area and the turbulence of the movement of coolant and flue gases, or rectangular cross-section with inserted turbulators. The heating water chamber is divided by horizontal jumpers with cross-flows, and the space between the furnace body and the heat block body has a helical surface. Thanks to the proposed design of the compact thermal unit, its manufacturability is achieved, with the possibility of easy disassembly for access to the internal and external surfaces of the heat exchanger.

Description

The utility model relates to the energy sector and can be used in boilers running on gas fuel to power central and individual heating circuits or to produce hot water.

In the field of heat exchange units of water heating devices or heating systems, one of the most urgent requirements is to provide manufacturers of such devices or systems with sets with the widest possible range of thermal powers, which, on the one hand, could satisfy the various needs of consumers, and, on the other sides would have extremely reduced dimensions and maximum efficiency. In this task, there are two contradictory requirements in the form of maximizing the heat transfer area to increase the efficiency of the boiler and transferring its operation to the condensing heat generation mode and, at the same time, reducing the dimensions of the heat exchanger.

Currently, heat exchange units equipped with fire tubes placed in appropriate thermally insulated shells are widely used due to their manufacturability and compactness. In particular, an externally located condensing boiler is known, containing a hydrothermal insulated housing, inside of which a gas burner device is installed, a fire tube heat exchanger with direct and return lines, a coaxial chimney connected to the chimney, two condensation heat exchangers made of non-corrosive materials, a centrifugal fan, characterized in that the centrifugal fan installed in the head of the internal passage of a coaxial chimney with the possibility of removing flue gases from the boiler, such as, for example, disclosed in patent RU 159664 in the name of A.A. Serdyukov. A common practice among manufacturers of such heat exchange units is to manufacture each heat exchange unit by installing in an appropriate special shell one or more heat exchangers having a specific heat transfer area selected in proportion to the required thermal output. However, this design of thermal blocks does not ensure manufacturability of the block elements, and also has a difficult-to-maintain design for periodic cleaning of the heat transfer surfaces of the condensation heat exchanger. The movement of flue gases has a complex spatial configuration with high aerodynamic resistance, which required the use of an exhaust fan in the design.

According to patent RU 2647012, the design of a heating condensing boiler is also known for heating the heating water of a circulating heating circuit, which has a housing that limits the heating water chamber and which has a combustion chamber connected to the heating water chamber, as well as a heat exchanger having external pipes through which the exhaust gases can flow. gases of the boiler furnace, and which can be surrounded on the outside by heating water, and a profile insert pushed into the outer pipes, which, to increase the internal surface of the outer pipe, has ribs extending in its longitudinal direction and is in heat-conducting contact with the outer pipe. But this design does not ensure proper compactness of the boiler, since heat transfer is carried out only in flame tubes, which have a complex design in the form of profile inserts and concavities.

The utility model is based on the task of creating a design of a thermal unit that would have a technologically advanced and compact design for creating mass production of boilers.

The problem is solved by the design of a thermal block of a condensing boiler, consisting of a heating water chamber and, pre-connected to it, a combustion chamber, as well as a heat exchanger having pipes through which the exhaust gases of the boiler furnace flow and which are surrounded on the outside by heating water, characterized in that the body consists of vertical cylindrical shells located coaxially, between which there is a coolant, and the inner shell is divided horizontally into two parts, the upper of which serves as a firebox, and the lower is a heating water chamber with a condensation heat exchanger consisting of a set of smoke pipes or a circular section with inserted turbulators, either oval cross-section, or rectangular cross-section with fins in the form of convex and, or concavities to increase both the cross-sectional area and the turbulence of the movement of coolant and flue gases, or rectangular cross-section with inserted turbulators. The heating water chamber is divided by horizontal jumpers with cross-flows, and the space between the furnace body and the heat block body has a helical surface.

Thanks to the proposed design of the thermal block, a thermal block is obtained that is manufacturable and compact and can be easily disassembled for access to structural elements.

The utility model is illustrated by drawings, where in Fig. 1 shows the appearance of the proposed thermal unit, and FIG. 2, 3 and 4 show its cross-section with various types of smoke pipes.

The thermal block consists of a cylindrical body 1, in the upper part of which a combustion chamber 4 made of stainless steel is located coaxially. A gas burner device 2 with an infrared burner 3 is installed in the cover of the thermal block. The cover of the thermal block has thermal insulation 6 to reduce heat losses to the environment.

The bottom of the combustion chamber is the entrance to the condensation heat exchanger of the heating water chamber 13, which is a set of vertical smoke pipes 7 made of stainless steel. Smoke pipes can have a round, oval or rectangular cross-section. To increase the heat exchange area and turbulence of the flue gas flow, turbulators 8 are inserted into the smoke pipes or the walls of the rectangular smoke pipes are finned.

In the lower part of the thermal unit body there is a coolant supply pipe 11, and in the upper part, a coolant outlet 12. To increase the time the coolant stays inside the thermal unit and to wash the entire heat transfer surface, inside the heating water chamber 13 there are horizontal jumpers 9, with overflows, to create tortuous path of liquid. For the same purpose, there is a screw surface 5 on the outer surface of the thermal block.

In the lower part of the heating block there is a collection of flue gases with a transition to the chimney 10, as well as the removal of condensate formed during the condensation of flue gases in the condensation block.

The thermal block of a condensing boiler operates as follows: hot flue gases produced by the combustion of a gas-air mixture in an infrared burner 3, located coaxially inside the combustion chamber 4 of the thermal block and fixed in its lid, moving in the radial direction, approach the cylindrical body of the combustion chamber, where they transmit its heat moving through the screw channel in the gap between the combustion chamber 4 and the body 1, the coolant. Next, the flue gases, which have already given up part of their heat, enter the smoke pipes 7 of the heating water chamber 13, where the heat transfer process also occurs. To increase the efficiency of heat transfer from flue gases, there are turbulators inside the smoke tubes, which intensively mix the flow of flue gases and themselves provide an additional area for heat transfer by radiation. When the temperature of the flue gases in the interturn space decreases, below the dew point, condensation falls out of them and, at the same time, latent heat of vaporization is released, which is additionally transferred to the coolant, increasing the efficiency of the boiler unit. The coolant moves countercurrent to the flow of flue gases, from bottom to top, to increase the likelihood of the heating unit transitioning to the condensing operating mode. To increase the residence time in the heat transfer zone, the heating water chamber is divided by horizontal jumpers, facilitating the complex, labyrinthine movement of the coolant.

To reduce the hydraulic resistance of the heating unit, smoke pipes can be made of oval or rectangular cross-section with a rounding, and they are located along the flow so that the incoming coolant flow meets the side of smaller width.

Changing the power of the heating unit in the range from 12 to 50 kW is carried out by changing the number of smoke pipes and their length, i.e. by changing the heat transfer area of the condensing unit.

Upon the exit of flue gases and condensate from the combustion pipes of the heating water chamber, flue gases are removed from the thermal block through the flue gas outlet pipe 10, and the condensate flows down and is removed from the thermal block through its pipe.

Thanks to the proposed design of the compact thermal unit, its manufacturability is achieved, with the possibility of easy disassembly for access to the internal and external surfaces of the heat exchanger.

Claims (8)

1. Thermal unit of a condensing boiler, consisting of a heating water chamber and, pre-connected to it, a combustion chamber, as well as a heat exchanger having pipes through which the exhaust gases of the boiler furnace flow and which are surrounded on the outside by heating water, characterized in that the body consists of vertical cylindrical shells and contains a vertical cylindrical body, in the upper part of which there is a coaxial firebox with an infrared burner, and in the lower part there is a heating water chamber with a condensation heat exchanger consisting of a set of round-section smoke tubes made of stainless steel, as well as supply and removal of coolant and flue gases, which move from top to bottom, and the coolant moves in the opposite direction, the heating water chamber is divided by horizontal jumpers with cross-flows. 2. The thermal block of a condensing boiler according to claim 1, characterized in that the space between the combustion chamber and the body of the thermal block has a helical surface. 3. The thermal unit of a condensing boiler according to claim 1, characterized in that turbulators are installed inside the smoke pipes. 4. The thermal unit of a condensing boiler according to claim 1, characterized in that the smoke pipes have an oval cross-section. 5. Thermal unit of a condensing boiler according to claim 1, characterized in that the smoke pipes have a rectangular cross-section with a rounding. 6. The thermal unit of a condensing boiler according to claim 5, characterized in that the walls of the smoke pipes have fins in the form of convex and/or concave. 7. The thermal unit of a condensing boiler according to claim 5, characterized in that grate-type turbulators are installed inside the smoke pipes. 8. The thermal block of a condensing boiler according to claim 5, characterized in that wave-type turbulators are installed inside the smoke pipes.