Heat-work conversion device and internal combustion engine waste heat recovery system

Abstract

The invention provides a heat-work conversion device and an internal combustion engine waste heat recovery system, the heat-work conversion device comprises a heat dissipation air cylinder, a heat insulation air cylinder, an output assembly and a heat exchange assembly, the heat dissipation air cylinder and the heat insulation air cylinder are both double-acting air cylinders, and an inner cavity is divided into two chambers by a piston and is provided with a piston rod. The output assembly comprises a mounting frame, an output shaft, connecting rods and a power generation device, the output shaft is provided with double crankshaft parts which are respectively connected with the two connecting rods and are connected with piston rods of the two air cylinders, the phase angle of the second connecting rod is 80-120 degrees earlier than that of the first connecting rod, and the output shaft and a main shaft of the power generation device synchronously rotate. The heat exchange assembly is provided with a heat exchanger with an inlet and an outlet, two heat absorbers are arranged in the heat exchange assembly, the heat absorbers communicate with corresponding air cylinder cavities and are connected with one-way conduction branches in parallel, related cavities and pipelines of the device are filled with heat exchange gas working media, and all the assemblies cooperate to achieve heat-work conversion. According to the technical scheme, efficient recovery and conversion of waste heat are achieved, system vibration is reduced, and energy output is improved.

Description

Technical Field

[0001] This application relates to the field of waste heat recovery technology, and more specifically, to a heat-power conversion device and an internal combustion engine waste heat recovery system. Background Technology

[0002] In internal combustion engine power systems, the combustion of fuels such as gasoline and diesel in the cylinder is the core process of energy conversion. However, the heat-to-work conversion efficiency of this process has natural limitations, and a large amount of heat energy is directly emitted into the environment with the high-temperature exhaust gas, resulting in the problem of low overall fuel energy utilization efficiency.

[0003] The thermal efficiency of gasoline engines is approximately 25%–30%, and the heat energy carried by their high-temperature exhaust gases accounts for 40%–45% of the total heat energy of fuel combustion. Diesel engines have a thermal efficiency of approximately 30%–45%, and their high-temperature exhaust gases also carry 25%–40% of the total heat energy of fuel combustion. The exhaust gases from these fuels are not only high in temperature but also carry a considerable amount of waste heat. If this waste heat energy can be effectively converted into mechanical energy and further into electrical energy, it will significantly improve the overall efficiency of fuel utilization and reduce energy waste. Therefore, the recovery and utilization of waste heat from high-temperature exhaust gases from internal combustion engines has become an important research direction in this field. However, currently, technologies for power output and electricity generation based on this type of waste heat energy have not yet been widely promoted and applied in the market.

[0004] To achieve waste heat recovery from high-temperature exhaust gases from internal combustion engines, relevant technical solutions have been explored in this field. For example, Chinese invention patent application number 202410083227.0 proposes a hot air engine that converts thermal energy into mechanical energy output by a power unit, and then converts the mechanical energy into pressure difference potential energy of a vacuum pump, attempting to achieve waste heat recovery and utilization. However, this technical solution still faces problems that urgently need to be solved in practical applications. In terms of energy conversion, the mechanical energy generated by this solution can only be theoretically reused within the system and cannot be used to output electrical energy externally, making it difficult to achieve diversified utilization of waste heat energy and external energy supply. In terms of structural design, one side of the piston in the device is a circulating working fluid while the other side is air, meaning that different media are used on both sides of the piston. During operation, the pressure difference between the two sides of the piston is large, which easily leads to gas leakage in the cylinder and makes it impossible to maintain long-term stable operation of the system. Furthermore, the large pressure difference between the two sides of the piston also causes significant vibration during system operation, resulting in a high failure rate of the equipment. These problems make it difficult for this technical solution to be industrialized and promoted, and it cannot meet the actual needs of this field for efficient, stable, and industrially viable recovery and utilization of high-temperature exhaust gas waste heat. Summary of the Invention

[0005] The purpose of this application is to provide a heat-to-work conversion device and an internal combustion engine waste heat recovery system, which can realize waste heat recovery, achieve efficient conversion of waste heat, reduce system vibration, and improve the level of external energy output.

[0006] In one aspect, a heat-work conversion device is provided, including a heat dissipation cylinder, an insulation cylinder, an output component, and a heat exchange component.

[0007] Both the radiator cylinder and the adiabatic cylinder are double-acting cylinders. The radiator cylinder includes a radiator body, a radiator piston, and a radiator piston rod connected to the radiator piston. The inner cavity of the radiator cylinder is divided into chambers A1 and A2 by the radiator piston, and the radiator piston rod extends from one side of chamber A2. The adiabatic cylinder includes an adiabatic cylinder body, an adiabatic piston, and an adiabatic piston rod connected to the adiabatic piston. The inner cavity of the adiabatic cylinder is divided into chambers B1 and B2 by the adiabatic piston, and the adiabatic piston rod extends from one side of chamber B2.

[0008] The output assembly includes a mounting bracket, an output shaft, a connecting rod, and a power generation device. The mounting bracket is fixedly installed, and the output shaft is rotatably mounted on the mounting bracket. One end of the output shaft is connected to the main shaft of the power generation device for synchronous rotation. A first crankshaft portion and a second crankshaft portion are respectively provided on the output shaft. The connecting rod includes a first connecting rod and a second connecting rod. The two ends of the first connecting rod are rotatably connected to the first crankshaft portion and the end of the heat dissipation piston rod, respectively. The two ends of the second connecting rod are rotatably connected to the second crankshaft portion and the end of the heat-insulating piston rod, respectively. The phase angle of the second connecting rod leads the phase angle of the first connecting rod by 80°~120°.

[0009] The heat exchange assembly includes a heat exchanger with a heat source inlet and a heat source outlet. A first heat absorber and a second heat absorber are arranged inside the heat exchanger. The two ends of the first heat absorber are respectively connected to chamber A1 and chamber B1 through pipes, and a first branch is connected in parallel with the first heat absorber, which is unidirectionally connected from chamber B1 to chamber A1. The two ends of the second heat absorber are respectively connected to chamber A2 and chamber B2 through pipes, and a second branch is connected in parallel with the second heat absorber, which is unidirectionally connected from chamber B2 to chamber A2.

[0010] The heat exchange working fluid is filled in the heat dissipation cylinder, the heat insulation cylinder, the first heat absorber, the second heat absorber, and the connecting pipes.

[0011] In one feasible solution, a sealed housing is included, the sealed housing including a sealing cover with an upper opening and a sealing plate covering the opening of the sealing cover, the sealing plate having a first through hole and a second through hole.

[0012] The output component is fixedly installed in a sealed enclosure, and the power generation device is equipped with a wire leading out to the outside of the sealed enclosure;

[0013] One end of the cooling cylinder is open, and the open end of the cooling cylinder faces the first through hole and is sealed and connected to the sealing plate. The cooling piston, the cooling cylinder and the sealing plate form cavity A2. The cooling piston rod passes through the first through hole and extends into the sealing box in a sliding seal manner.

[0014] One end of the insulated cylinder is open, and the open end of the insulated cylinder faces the second through hole and is sealed and connected to the sealing plate. The insulated piston, the insulated cylinder and the sealing plate form cavity B2. The insulated piston rod passes through the second through hole and extends into the sealing box in a sliding seal manner.

[0015] The sealed chamber is filled with a heat exchange working gas.

[0016] In one feasible embodiment, a guide plate is also installed on the mounting bracket. The guide plate is provided with a first guide hole and a second guide hole that are coaxial with the first through hole and the second through hole, respectively. The heat dissipation piston rod passes through the first guide hole, and the heat insulation piston rod passes through the second guide hole.

[0017] In one feasible solution, the outer wall of the heat dissipation cylinder is provided with several fin structures for heat dissipation.

[0018] In one feasible embodiment, a plurality of first fins extending toward the ends are provided on both sides of the heat dissipation piston, and a plurality of second fins extending toward the heat dissipation piston are provided at both ends of the internal cavity of the heat dissipation cylinder; the first fins on the same side of the heat dissipation piston are interspersed in the intervals of the second fins on the corresponding side.

[0019] In one feasible solution, a first check valve is installed on the first branch, which allows unidirectional flow from chamber B1 to chamber A1; a second check valve is installed on the second branch, which allows unidirectional flow from chamber B2 to chamber A2.

[0020] In one feasible embodiment, the heat exchange assembly further includes a first regenerator and a second regenerator; the first regenerator is disposed on the pipeline connecting the first absorber and the A1 cavity, and the second regenerator is disposed on the pipeline connecting the second absorber and the A2 cavity.

[0021] In one feasible embodiment, the phase angle of the second link leads the phase angle of the first link by 90°.

[0022] In one feasible embodiment, the output assembly also includes a flywheel mounted on the end of the output shaft away from the power generation device.

[0023] In one feasible solution, at least one openable and closable first working fluid supply port is provided in the heat dissipation cylinder, the insulation cylinder, the first heat absorber, the second heat absorber, and the connecting pipeline.

[0024] In one feasible solution, a second working fluid supply port that can be opened and closed is provided on the sealed housing.

[0025] In one feasible embodiment, the heat-work conversion device further includes a control device, a gas working fluid supply device, and a pressure sensor. The gas working fluid supply device is connected to a second working fluid supply port. The pressure sensor is mounted on the sealed housing and used to measure the pressure in the sealed housing. The control device is electrically connected to the gas working fluid supply device and the pressure sensor. A comparison pressure T0 is preset in the control device.

[0026] Methods for regulating the pressure in a sealed enclosure include:

[0027] The control device controls the pressure sensor to collect the real-time pressure T1 in the sealed box according to the set period;

[0028] The control device determines the magnitude of the real-time pressure T1 and the comparison pressure T0;

[0029] If the real-time pressure T1 is greater than or equal to the comparison pressure T0, then maintain the current state;

[0030] If the real-time pressure T1 is less than the comparison pressure T0, the control device controls the gas working medium supply device to replenish the heat exchange gas working medium into the sealed box until the real-time pressure T1 is greater than or equal to the comparison pressure T0.

[0031] Secondly, a waste heat recovery system for an internal combustion engine is also provided, including an internal combustion engine and the aforementioned heat-power conversion device, wherein the exhaust port of the internal combustion engine is connected to the heat source inlet of the heat exchanger of the heat-power conversion device.

[0032] Compared with the prior art, the beneficial effects of this application include at least the following: the heat-to-work conversion device of this application solves the problems of low waste heat recovery and utilization efficiency, inability to output electrical energy, easy leakage and vibration during equipment operation and high failure rate in the prior art through the structural design and coordinated cooperation of each component, while enabling the device to have stable heat-to-work conversion capability and achieving good application results.

[0033] Specifically, the device sets both the heat dissipation cylinder and the adiabatic cylinder as double-acting cylinders, and fills the heat dissipation cylinder body, the adiabatic cylinder body, the first heat absorber, the second heat absorber, and all connecting pipes with the same heat exchange working gas. This ensures that both sides of the heat dissipation piston and the adiabatic piston use the same heat exchange working gas, effectively reducing the pressure difference between the two sides of the piston. This improves the problem of excessive pressure difference caused by different media on both sides of the piston in the prior art, thereby reducing the possibility of working gas leakage. At the same time, it alleviates the vibration phenomenon during equipment operation, reduces the failure rate of the device, and improves the overall operational stability.

[0034] The device's output assembly incorporates an integrated power generation unit, which functions as both an electric motor and a generator. During startup, it provides initial starting kinetic energy to the output shaft in the form of an electric motor, driving the output shaft and its connecting rods and piston rods. This eliminates the need for an additional starting mechanism, simplifying the device's structure. Once the device is operating normally, the power generation unit switches to generator mode, driven by the output shaft to convert mechanical energy into electrical energy. This successfully solves the problem in existing technologies where the mechanical energy converted from waste heat can only be utilized internally and cannot be output as electrical energy. It achieves the dual conversion and external supply of high-temperature waste heat into both mechanical and electrical energy, improving the overall utilization efficiency of energy after fuel combustion and reducing energy waste.

[0035] The first and second crankshaft sections on the output shaft, in conjunction with the first and second connecting rods, form a phase difference of 80° to 120°. This ensures precise timing coordination between the reciprocating motions of the cooling piston and the adiabatic piston, allowing for the orderly connection of the heat absorption, work, and reflux processes of the working fluid in the cooling cylinder and the adiabatic cylinder. This guarantees the continuity of the heat-work conversion cycle and improves the discontinuous waste heat recovery process in existing technologies. Simultaneously, the first and second absorbers in the heat exchange assembly are connected in parallel with the unidirectional first and second branches, respectively, achieving directional reflux of the heat exchange gas working fluid from the adiabatic cylinder to the cooling cylinder. This prevents reverse flow of the working fluid, enabling it to form a closed loop between the cooling cylinder, heat exchanger, and adiabatic cylinder, continuously completing the heat-work conversion process of heat absorption, work, and heat dissipation, thus improving the efficiency of high-temperature waste heat recovery. Furthermore, since the adiabatic piston can perform work in both directions, it can achieve nearly double the energy output, thereby achieving superior waste heat utilization capabilities.

[0036] Overall, the device achieves synchronous circulation and work of the dual working fluids through a compact structural design, with all components working in coordination. While solving many problems of existing technologies, it enables the device to recover and convert high-temperature waste heat in a stable manner over a long period of time. Attached Figure Description

[0037] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0038] Figure 1 This is a schematic diagram illustrating the composition of a heat-work conversion device according to an embodiment of this application.

[0039] Figure 2 This is a schematic diagram illustrating the composition of another heat-work conversion device according to an embodiment of this application.

[0040] In the diagram: 1. Sealing cover; 101. First working fluid supply port; 102. Second working fluid supply port; 2. Sealing plate; 21. First through hole; 22. Second through hole; 3. Output assembly; 31. Mounting bracket; 32. Output shaft; 33. Generator; 331. First crankshaft section; 332. Second crankshaft section; 34. First connecting rod; 35. Second connecting rod; 36. Guide plate; 37. Flywheel; 4. Cooling cylinder; 41. Cooling cylinder body; 411. Fin structure; 42. Cooling piston; 421. First fin; 422. Second fin; 43. Heat dissipation piston rod; 5. Insulating cylinder; 51. Insulating cylinder body; 52. Insulating piston; 53. Insulating piston rod; 6. Heat exchanger; 601. Heat source inlet; 602. Heat source outlet; 61. First absorber; 611. First branch; 612. First check valve; 62. Second absorber; 621. Second branch; 622. Second check valve; 7. First regenerator; 8. Second regenerator; 9. Gas working fluid supply device; 91. Pressure sensor; 10. Control device. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0042] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0043] like Figure 1 As shown, this application provides an embodiment of a heat-to-work conversion device, including a heat dissipation cylinder 4, an adiabatic cylinder 5, an output component 3, and a heat exchange component.

[0044] Both the cooling cylinder 4 and the adiabatic cylinder 5 are double-acting cylinders. The cooling cylinder 4 includes a cooling cylinder body 41, a cooling piston 42, and a cooling piston rod 43 connected to the cooling piston 42. The inner cavity of the cooling cylinder 4 is divided into chamber A1 and chamber A2 by the cooling piston 42, and the cooling piston rod 43 extends from one side of chamber A2. The adiabatic cylinder 5 includes an adiabatic cylinder body 51, an adiabatic piston 52, and an adiabatic piston rod 53 connected to the adiabatic piston 52. The inner cavity of the adiabatic cylinder 5 is divided into chamber B1 and chamber B2 by the adiabatic piston 52, and the adiabatic piston rod 52 extends from one side of chamber B2.

[0045] The output assembly 3 includes a mounting bracket 31, an output shaft 32, a connecting rod, and a power generation device 33. The mounting bracket 31 is fixedly mounted, and the output shaft 32 is rotatably mounted on the mounting bracket 31. One end of the output shaft 32 is connected to the main shaft of the power generation device 33 for synchronous rotation. A first crankshaft portion 331 and a second crankshaft portion 332 are respectively provided on the output shaft 32. The connecting rod includes a first connecting rod 34 and a second connecting rod 35. The two ends of the first connecting rod 34 are rotatably connected to the first crankshaft portion 331 and the end of the heat dissipation piston rod 43, respectively. The two ends of the second connecting rod 35 are rotatably connected to the second crankshaft portion 332 and the end of the heat-insulating piston rod 53, respectively. The phase angle of the second connecting rod 35 leads the phase angle of the first connecting rod 34 by 80° to 120°, preferably by 90°.

[0046] The heat exchange assembly includes a heat exchanger 6 with a heat source inlet 601 and a heat source outlet 602. A first heat absorber 61 and a second heat absorber 62 are arranged inside the heat exchanger 6. The two ends of the first heat absorber 61 are respectively connected to chamber A1 and chamber B1 through pipes, and a first branch 611 with unidirectional conduction from chamber B1 to chamber A1 is connected in parallel with the first heat absorber 61. The two ends of the second heat absorber 62 are respectively connected to chamber A2 and chamber B2 through pipes, and a second branch 621 with unidirectional conduction from chamber B2 to chamber A2 is connected in parallel with the second heat absorber 62.

[0047] The heat exchange working fluid is filled in the heat dissipation cylinder 61, the heat insulation cylinder 51, the first heat absorber 61, the second heat absorber 62, and the connecting pipes.

[0048] It should be noted that the power generation device 33 can function as either a generator or an electric motor. When the heat-power conversion device of this application is started, the power generation device 33 is controlled to rotate as an electric motor, driving the output shaft 32 to rotate. After the heat-power conversion device is working, the power generation device 33 functions as a generator, driven by the output shaft 32 to generate electricity.

[0049] In some specific embodiments, such as Figure 1 As shown, the outer wall of the heat dissipation cylinder 41 is provided with several fin structures 411 for heat dissipation.

[0050] After the heat-work conversion device in this embodiment is integrated, a certain pressure of heat exchange gas working medium is first introduced into the heat dissipation cylinder 41, the insulation cylinder 51, the first heat absorber 61, the second heat absorber 62 and each connecting pipeline to lay the medium foundation for the device's cyclic operation.

[0051] The high-temperature exhaust gas heat source enters the heat exchanger 6 through the heat source inlet 601, heating the first heat absorber 61 and the second heat absorber 62 inside, so that the heat exchange working gas inside the two heat absorbers completes the initial temperature rise; at this time, the control generator 33 works in the form of an electric motor, providing initial starting kinetic energy for the output shaft 32, driving the output shaft 32 to rotate. The output shaft 32 drives the first connecting rod 34 and the second connecting rod 35 to move through the first crankshaft part 331 and the second crankshaft part 332 respectively, thereby driving the heat dissipation piston rod 43 and the adiabatic piston rod 53 to reciprocate. The phase angle of the second connecting rod 35 leads the phase angle of the first connecting rod 34 by 80°~120°, realizing the coordinated movement of the two piston rods.

[0052] When the second connecting rod 35 drives the adiabatic piston rod 53 to position the adiabatic piston 52 at the upper part of the adiabatic cylinder 5 (that is, compressing the B1 chamber), the first crankshaft part 331 drives the first connecting rod 34 and the cooling piston rod 43, causing the cooling piston 42 to move upward. At this time, the gas in the A1 chamber of the cooling cylinder 4 is compressed and heat dissipation is completed. The A2 chamber of the cooling cylinder 4 draws in the heat exchange working fluid that returns from the adiabatic cylinder 5 through the first branch 611. The pressure in the B1 chamber of the adiabatic cylinder 5 gradually increases as the working fluid is filled, while the pressure in the B2 chamber decreases synchronously.

[0053] Subsequently, under the continuous drive of the output shaft 32, the adiabatic piston 52 begins to move downward, while the heat dissipation piston 42 remains in an upward state. The heat exchange working gas in the A1 chamber of the heat dissipation cylinder 4 flows through the pipeline and enters the first heat absorber 61 to complete heat absorption. After absorbing the heat energy of the high-temperature exhaust gas, the working gas converts it into its own internal energy, achieving a synchronous increase in temperature and pressure. The heated and pressurized working gas enters the B1 chamber of the adiabatic cylinder 5 to provide energy for subsequent work.

[0054] Driven by the crankshaft of the output shaft 32, the adiabatic piston 52 continues to move downward. The heat exchange working gas in the B1 chamber of the adiabatic cylinder 5 undergoes adiabatic expansion, pushing the adiabatic piston 52 to do work. This mechanical energy is transmitted to the output shaft 32 through the adiabatic piston rod 53 and the second connecting rod 35. At this time, the power generation device 33 switches to the form of a generator, driven by the output shaft 32 to realize the conversion of mechanical energy into electrical energy, completing the process of outputting mechanical energy or electrical energy. During this process, the B2 chamber of the adiabatic cylinder 5 continuously exhausts gas, while the cooling piston 42 remains almost stationary at the upper part of the cooling cylinder 4 (not that the piston stops moving completely, but that the piston is in the transition stage of reversing the movement).

[0055] Driven by the output shaft 32, the adiabatic piston 52 moves to the lower part of the adiabatic cylinder 5 and remains nearly stationary (not that the piston stops moving completely, but that the piston is in the transition phase of reversal), while the cooling piston 42 begins to move downwards. Afterwards, the heat exchange working gas in chamber B1 of the adiabatic cylinder 5 flows back to chamber A1 of the cooling cylinder 4 through the first branch 611, causing the pressure in chamber B1 to decrease. Meanwhile, the gas in chamber A2 of the cooling cylinder 4 is compressed under the pressure of the cooling piston 42, and the pressure gradually increases, preparing for subsequent heat absorption.

[0056] Then, under the action of the output shaft 32, the adiabatic piston 52 begins to move upward, while the heat dissipation piston 42 remains in a downward state. The heat exchange working gas in the A2 chamber of the heat dissipation cylinder 4 flows through the pipeline into the second heat absorber 62 to complete heat absorption. The heat energy of the external high-temperature exhaust gas is converted into the internal energy of the working gas. After the working gas is heated and pressurized, it enters the B2 chamber of the adiabatic cylinder 5.

[0057] Under the action of the output shaft 32, the adiabatic piston 52 continues to move upward. The working fluid in chamber B1 of the adiabatic cylinder 5 continuously flows back to chamber A1 of the cooling cylinder 4 through the first branch 611. At the same time, the heat exchange gas working fluid in chamber B2 undergoes adiabatic expansion, pushing the adiabatic piston 52 to do work again. The mechanical energy is transmitted to the output shaft 32 through the adiabatic piston rod 53 and the second connecting rod 35, continuing to drive the power generation device 33 to generate electricity, until the adiabatic piston 52 moves to the upper part of the adiabatic cylinder 5, thus completing a complete heat-work conversion cycle. Subsequent devices will continue to cycle in this manner to achieve continuous recovery of waste heat from high-temperature exhaust gas and stable output of mechanical and electrical energy.

[0058] Throughout the entire cycle, the second branch 621, which is connected in parallel next to the second absorber 62, simultaneously realizes the directional reflux of the working fluid from the adiabatic cylinder 5B2 chamber to the heat dissipation cylinder 4A2 chamber. This, together with the first branch 611, ensures the orderly reflux of the working fluid, enabling the heat exchange working fluid to circulate between the heat dissipation cylinder 4 and the adiabatic cylinder 5, continuously completing the entire process of heat absorption, work, heat dissipation, and reflux, maximizing the utilization of the waste heat energy of the high-temperature exhaust gas.

[0059] Based on the above working principle, the heat-to-work conversion device of this application, through the structural design and coordinated operation of its components, specifically addresses the problems of low waste heat recovery efficiency, inability to output electrical energy, and high failure rate and leakage during equipment operation in existing technologies. Simultaneously, it enables the device to possess stable heat-to-work conversion capabilities, achieving excellent application results. The device configures both the cooling cylinder 4 and the adiabatic cylinder 5 as double-acting cylinders, and fills the cooling cylinder 41, adiabatic cylinder 51, first absorber 61, second absorber 62, and all connecting pipes with the same heat exchange working gas. This ensures that both sides of the cooling piston 42 and the adiabatic piston 52 use the same heat exchange working gas, effectively reducing the pressure difference between the two sides of the piston. This improves upon the problem of excessive pressure difference caused by different media on both sides of the piston in existing technologies, thereby reducing the possibility of working gas leakage and mitigating vibration during equipment operation, reducing the device's failure rate, and improving overall operational stability. Furthermore, since the adiabatic piston 52 can perform work in both directions, it can achieve nearly double the energy output, thus achieving superior waste heat utilization capabilities.

[0060] The output component 3 of the device is equipped with an integrated power generation device 33, which can function as both an electric motor and a generator. During the start-up phase, it provides initial starting kinetic energy to the output shaft 32 in the form of an electric motor, driving the output shaft 32 and each connecting rod and piston rod to move. No additional starting mechanism is required, which simplifies the device structure. After the device is working normally, the power generation device 33 switches to generator mode and is driven by the output shaft 32 to realize the conversion of mechanical energy into electrical energy. This successfully solves the problem in the prior art that the mechanical energy converted from waste heat can only be used internally and cannot be output as electrical energy. It realizes the dual conversion and external supply of high-temperature waste heat into mechanical energy and electrical energy, improves the comprehensive utilization efficiency of energy after fuel combustion, and reduces energy waste.

[0061] The first crankshaft section 331 and the second crankshaft section 332 on the output shaft 32, together with the first connecting rod 34 and the second connecting rod 35, form a phase difference of 80°~120°. This allows the reciprocating motion of the cooling piston 42 and the adiabatic piston 52 to achieve precise timing coordination, ensuring that the heat absorption, work, and reflux processes of the working fluid in the cooling cylinder 4 and the adiabatic cylinder 5 are orderly connected. This guarantees the continuity of the heat-work conversion cycle and improves the problem of discontinuous waste heat recovery in the prior art. At the same time, the first heat absorber 61 and the second heat absorber 62 in the heat exchange assembly are connected in parallel with the unidirectional first branch 611 and the second branch 621, respectively. This realizes the directional reflux of the heat exchange working fluid from the adiabatic cylinder 5 to the cooling cylinder 4, avoiding reverse flow of the working fluid. This allows the working fluid to form a closed loop between the cooling cylinder 4, the heat exchanger 6, and the adiabatic cylinder 5, continuously completing the heat-work conversion process of heat absorption, work, and heat dissipation, and improving the efficiency of high-temperature waste heat recovery.

[0062] Overall, the device achieves synchronous circulation and work of the dual working fluids through a compact structural design. The components work in coordination, solving many problems of existing technologies while enabling the device to recycle and convert high-temperature exhaust heat stably over a long period of time. It provides a practical way to recover and utilize waste heat from internal combustion engines and has good application value.

[0063] In some cases, because one end of the piston rod is connected to the piston and the other end extends outside the cylinder, the sliding seal of the piston rod may leak during long-term reciprocating motion, leading to leakage and reduction of the heat exchange medium, affecting the circulation efficiency, and causing the preheating and utilization circulation device to malfunction and shut down.

[0064] Therefore, in some embodiments, such as Figure 1 As shown, the heat-power conversion device also includes a sealed housing, which includes a sealing cover 1 with an upper opening and a sealing plate 2 covering the opening of the sealing cover 1. The sealing plate 2 has a first through hole 21 and a second through hole 22. The output component 3 is fixedly installed in the sealed housing, and the power generation device 33 is provided with a wire leading out to the outside of the sealed housing.

[0065] One end of the heat dissipation cylinder 41 is open, with the open end facing the first through hole 21 and sealed to the sealing plate 2. The heat dissipation piston 42, the heat dissipation cylinder 41, and the sealing plate 2 form cavity A2. The heat dissipation piston rod 43 passes through the first through hole 21 and extends into the sealed housing in a sliding seal manner. One end of the heat insulation cylinder 51 is open, with the open end facing the second through hole 22 and sealed to the sealing plate 2. The heat insulation piston 52, the heat insulation cylinder 51, and the sealing plate 2 form cavity B2. The heat insulation piston rod 53 passes through the second through hole 22 and extends into the sealed housing in a sliding seal manner. The sealed housing is filled with a heat exchange working gas.

[0066] In the heat-work conversion device of this embodiment, to improve the problem of working fluid leakage that easily occurs during long-term reciprocating motion of the piston rod sliding seal, a sealed box structure is added to the device. The heat dissipation piston 42, the heat dissipation cylinder 41, and the sealing plate 2 together form cavity A2, and the heat insulation piston 52, the heat insulation cylinder 51, and the sealing plate 2 together form cavity B2. At the same time, the inside of the sealed box is also filled with heat exchange gas working fluid, so that both sides of the sliding seal of the heat dissipation piston rod 43 and the heat insulation piston rod 53 are in the environment of heat exchange gas working fluid. This reduces the internal and external pressure difference at the sliding seal of the heat dissipation piston rod 43 and the heat insulation piston rod 53, reduces the probability of working fluid leakage at the piston rod sliding seal, and helps to extend the service life of the sliding seal.

[0067] Meanwhile, even if leakage occurs at the sliding seal of the heat dissipation piston rod 43 and the heat insulation piston rod 53, the normal circulation of the device can be maintained as long as the heat exchange working medium inside the sealed box can maintain a relatively high pressure (for example, close to the pressure in chamber A2 and / or chamber B2).

[0068] In some embodiments, such as Figure 1 As shown, a guide plate 36 can also be installed on the mounting bracket 31. The guide plate 36 is provided with a first guide hole and a second guide hole that are coaxial with the first through hole 21 and the second through hole 22, respectively. The heat dissipation piston rod 43 passes through the first guide hole, and the heat insulation piston rod 53 passes through the second guide hole. This ensures the precise movement position of the heat dissipation piston rod 43 and the heat insulation piston rod 53, reduces unnecessary shaking, and thus improves the stability of the sliding seal of the heat dissipation piston rod 43 and the heat insulation piston rod 53.

[0069] In some embodiments, such as Figure 1 As shown, both sides of the heat dissipation piston 42 can be provided with a plurality of first fins 421 extending toward the end, and both ends of the internal cavity of the heat dissipation cylinder 41 are provided with a plurality of second fins 422 extending toward the heat dissipation piston 42; the first fins 421 on the same side of the heat dissipation piston 42 are interspersed in the intervals of the second fins 422 on the corresponding side, so as to significantly improve the heat exchange efficiency.

[0070] In some embodiments, such as Figure 1 As shown, a first check valve 612 is provided on the first branch 611, which allows unidirectional flow from chamber B1 to chamber A1. A second check valve 622 is provided on the second branch 621, which allows unidirectional flow from chamber B2 to chamber A2.

[0071] It should be noted that, because the internal resistance of the first absorber 61 is much greater than the resistance in the first branch 611, when the B1 chamber is unidirectionally connected to the A1 chamber via the first one-way valve 612, the gaseous working fluid will hardly flow through the interior of the first absorber 61. Similarly, because the internal resistance of the second absorber 62 is much greater than the resistance in the second branch 621, when the B2 chamber is unidirectionally connected to the A2 chamber via the second one-way valve 622, the gaseous working fluid will hardly flow through the interior of the second absorber 62.

[0072] In some embodiments, such as Figure 1 As shown, the heat exchange assembly also includes a first regenerator 7 and a second regenerator 8. The first regenerator 7 is disposed on the pipeline connecting the first absorber 61 and cavity A1, specifically on the pipeline from the intersection of the first branch 611 and the first absorber 61 to cavity A1. The second regenerator 8 is disposed on the pipeline connecting the second absorber 62 and cavity A2, specifically on the pipeline from the intersection of the second branch 621 and the second absorber 62 to cavity A2.

[0073] In the heat-to-work conversion device of this embodiment, the arrangement of the first regenerator 7 and the second regenerator 8, in conjunction with other components of the heat exchange assembly, completes the heat exchange and energy utilization of the working fluid, further optimizing the energy utilization efficiency of the heat-to-work conversion. During the heat-to-work conversion cycle of the device, the heat exchange working fluid flowing back from the B1 chamber of the adiabatic cylinder 5 to the A1 chamber via the first branch 611 will first flow through the first regenerator 7, and the heat exchange working fluid flowing back from the B2 chamber of the adiabatic cylinder 5 to the A2 chamber via the second branch 621 will first flow through the second regenerator 8. The recirculated working fluid completes heat release in the regenerator, while the working fluid to be absorbed flowing out of the A1 and A2 chambers of the heat dissipation cylinder 4 and heading to the first absorber 61 and the second absorber 62 will also flow through the first regenerator 7 and the second regenerator 8 respectively, absorbing the heat released by the recirculated working fluid to achieve preheating. This process allows for the full recovery and utilization of the waste heat of the return working fluid, reducing energy waste caused by direct heat loss. It ensures that the working fluid to be absorbed has a certain temperature before entering the first heat absorber 61 and the second heat absorber 62, enabling it to achieve faster temperature and pressure increases when absorbing heat energy from high-temperature waste gas. This improves the heat absorption efficiency and energy conversion efficiency of the working fluid, while also making the temperature change of the heat exchange gas working fluid more gradual. This reduces the thermal shock to pipelines and components caused by sudden temperature changes, extends the service life of pipelines and heat exchange components, and makes the heat-work conversion cycle of the device more efficient and stable.

[0074] The regenerator used in this embodiment is a heat exchange component that uses the temperature difference between working fluids to achieve heat transfer. In the application scenario of this device, specific structures such as partition regenerator, regenerative regenerator, and plate regenerator can be selected according to the actual heat exchange requirements and installation space. As long as the heat exchange between the working fluid to be absorbed and the return working fluid in the device can be realized, and the preheating of the working fluid to be absorbed and the release of the waste heat of the return working fluid can be used as specific implementation methods of this regenerator.

[0075] In some embodiments, such as Figure 1 As shown, the output component 3 may also include a flywheel 37, which is mounted on the end of the output shaft 32 away from the power generation device 33.

[0076] In the heat-to-work conversion device of this embodiment, a flywheel 37 is added to the output component 3. The flywheel 37 is installed at the end of the output shaft 32 away from the power generation device 33 and can rotate synchronously with the output shaft 32. When the device is running, the adiabatic piston 52 does work to drive the output shaft 32 to rotate. The flywheel 37 stores rotational inertial kinetic energy as it rotates. When the device is in the piston reversal stage of the heat-to-work conversion cycle, and the kinetic energy transmitted to the output shaft 32 fluctuates or the speed is prone to change, the flywheel 37 will release the stored inertial kinetic energy, driving the output shaft 32 to maintain a stable and continuous rotation state. This avoids the output shaft 32 from experiencing sudden changes in speed or jamming, allowing the power generation device 33 to generate electricity continuously and stably, ensuring the uniformity of power output. At the same time, the inertial speed stabilization effect of the flywheel 37 can also alleviate the transmission impact between the connecting rod and the crankshaft during the reversal stage, reduce the wear of various transmission components of the output component 3, extend the service life of the components, make the power transmission of the device smoother, and further improve the overall stability and reliability of operation.

[0077] In some embodiments, such as Figure 1 As shown, at least one openable and closable first working fluid supply port 101 is provided in the heat dissipation cylinder 41, the heat insulation cylinder 51, the first heat absorber 61, the second heat absorber 62, and the connecting pipeline.

[0078] In some embodiments, such as Figure 1 As shown, a second working fluid supply port 102 that can be opened and closed is provided on the sealed box.

[0079] In the heat-to-work conversion device of this embodiment, during long-term operation, the heat exchange working gas may experience a decrease in quantity due to minor leakage at the seal and operating losses. In this case, the working gas can be replenished into the pipelines of the heat dissipation cylinder 41, the insulation cylinder 51, and the heat exchange components by opening the first working gas supply port 101, and into the sealed box by opening the second working gas supply port 102. This ensures that the working gas pressure and quantity required for heat-to-work conversion are always maintained in each chamber, pipeline, and sealed box of the device, avoiding a decrease in the efficiency of the heat-to-work conversion cycle due to insufficient working gas, preventing the device from shutting down due to lack of working gas, and allowing the device to stably complete waste heat recovery and conversion for a long time. At the same time, the working gas can be filled through the two supply ports during the initial commissioning and maintenance restart of the device, improving the convenience of device operation and maintenance.

[0080] In some embodiments, the pressure of the heat exchange working gas inside the sealed housing can be greater than the pressure outside the sealed housing. The pressures in the heat dissipation cylinder 41, the adiabatic cylinder 51, the first absorber 61, the second absorber 62, and the connecting pipes are also generally greater than the pressure outside the sealed housing. Furthermore, the positive pressure environment inside the sealed housing and the working gas pressures in the various components of the device form a more balanced pressure field, reducing additional wear on the piston rod sliding seal structure caused by excessive pressure differences, extending the service life of the sealing components, reducing the maintenance frequency of the device, and enabling the entire heat-power conversion device to complete the recovery and conversion of high-temperature exhaust heat from the internal combustion engine in a long-term and stable manner.

[0081] In some embodiments, such as Figure 2 As shown, the heat-to-work conversion device may also include a control device 10, a gas supply device 9, and a pressure sensor 91. The gas supply device 9 is connected to the second working fluid supply port 102. The pressure sensor 91 is installed on the sealed housing and is used to measure the pressure in the sealed housing. The control device 10 is electrically connected to the gas supply device 9 and the pressure sensor 91. A comparison pressure T0 is preset in the control device 10.

[0082] Methods for regulating the pressure in a sealed enclosure include:

[0083] Control device 10 controls pressure sensor 81 to collect real-time pressure T1 in the sealed box according to a set cycle;

[0084] Control device 10 determines the magnitude of real-time pressure T1 and comparison pressure T0;

[0085] If the real-time pressure T1 is greater than or equal to the comparison pressure T0, then maintain the current state;

[0086] If the real-time pressure T1 is less than the comparison pressure T0, the control device 10 controls the gas working medium supply device 9 to replenish the heat exchange gas working medium into the sealed box until the real-time pressure T1 is greater than or equal to the comparison pressure T0.

[0087] In the heat-work conversion device of this embodiment, a control device 10, a gas working fluid supply device 9, and a pressure sensor 91 are added. The gas working fluid supply device 9 is connected to the second working fluid supply port 102 on the sealed box. The pressure sensor 91 is installed on the sealed box to detect the internal pressure. The control device 10 is electrically connected to the gas working fluid supply device 9 and the pressure sensor 91. The control device 10 is preset with the target comparison pressure T0 of the sealed box. During operation, the control device 10 controls the pressure sensor 91 to collect the real-time pressure T1 in the sealed chamber according to a set cycle. It then automatically compares T1 with the preset T0. If the real-time pressure T1 is not lower than T0, the control device 10 maintains the current state of all components without requiring additional working fluid. If the real-time pressure T1 is lower than T0, it indicates a slight leakage of working fluid within the sealed chamber, leading to insufficient pressure. The control device 10 immediately activates the gas working fluid replenishment device 9, replenishing the heat exchange working fluid into the sealed chamber through the second working fluid replenishment port 102 until the real-time pressure T1 detected by the pressure sensor 91 reaches or exceeds T0. The control device 10 then stops the gas working fluid replenishment device 9. This structure achieves automatic monitoring and pressure replenishment of the internal pressure of the sealed chamber without the need for manual real-time monitoring and control. It continuously maintains a positive pressure environment in the sealed chamber, ensuring the sealing effect at the piston rod sliding seal, reducing working fluid leakage, stabilizing the efficiency of the heat-work conversion cycle, reducing manual maintenance costs, improving the automation and intelligence level of the device's operation, and making the pressure control of the device more precise and timely.

[0088] In this embodiment, the pressure sensor 91 can be a piezoresistive, piezoelectric, or strain gauge pressure sensor, the gas working fluid supply device 9 can be a gas booster pump, a working fluid storage cylinder, and a delivery valve group, and the control device 10 can be a PLC controller, a microcontroller, or an embedded control module.

[0089] It should be noted that when the real-time pressure T1 is not lower than the comparison pressure T0, the pressure difference between cavity A2 and the sealed housing, and the pressure difference between cavity B2 and the sealed housing can be reduced. This ensures that the internal and external pressure differences at the sliding seal of the heat dissipation piston rod 43 and the heat insulation piston rod 53 are within a relatively small range, thereby protecting the lifespan of the sliding seal. In a specific embodiment, the value of the comparison pressure T0 can be equal to the median pressure in cavity A2, or equal to the median pressure in cavity B2, or the average of the medians of cavities A2 and B2, etc.

[0090] In addition, this application also provides an internal combustion engine waste heat recovery system, including an internal combustion engine and the aforementioned heat conversion device. The exhaust port of the internal combustion engine is connected to the heat source inlet 601 of the heat exchanger 6 of the heat conversion device, so as to realize the waste heat recovery and utilization of the high temperature exhaust gas of the internal combustion engine.

[0091] In some embodiments, the internal combustion engine waste heat recovery system may further include an energy storage battery, which is electrically connected to the power generation device 33 for storing the electrical energy generated by the power generation device 33.

[0092] The above description is only a partial embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A heat-to-work conversion device, characterized in that, It includes a cooling cylinder (4), an insulating cylinder (5), an output component (3), and a heat exchange component; Both the heat dissipation cylinder (4) and the heat insulation cylinder (5) are double-acting cylinders; The cooling cylinder (4) includes a cooling cylinder body (41), a cooling piston (42) and a cooling piston rod (43) connected to the cooling piston (42). The inner cavity of the cooling cylinder (4) is divided into a cavity A1 and a cavity A2 by the cooling piston (42). The cooling piston rod (43) extends out from one side of the cavity A2. The insulated cylinder (5) includes an insulated cylinder body (51), an insulated piston (52), and an insulated piston rod (53) connected to the insulated piston (52). The inner cavity of the insulated cylinder (5) is divided into a B1 cavity and a B2 cavity by the insulated piston (52), and the insulated piston rod (52) extends out from one side of the B2 cavity. The output assembly (3) includes a mounting bracket (31), an output shaft (32), a connecting rod, and a power generation device (33). The mounting bracket (31) is fixedly installed, and the output shaft (32) is rotatably mounted on the mounting bracket (31). One end of the output shaft (32) is connected to the main shaft of the power generation device (33) for synchronous rotation. A first crankshaft portion (331) and a second crankshaft portion (332) are respectively provided on the output shaft (32). The connecting rod includes a first connecting rod (34) and a second connecting rod (35). The two ends of the first connecting rod (34) are rotatably connected to the ends of the first crankshaft portion (331) and the heat dissipation piston rod (43), respectively. The two ends of the second connecting rod (35) are rotatably connected to the ends of the second crankshaft portion (332) and the heat insulation piston rod (53), respectively. The phase angle of the second connecting rod (35) leads the phase angle of the first connecting rod (34) by 80°~120°. The heat exchange assembly includes a heat exchanger (6) with a heat source inlet (601) and a heat source outlet (602). A first heat absorber (61) and a second heat absorber (62) are provided inside the heat exchanger (6). The two ends of the first heat absorber (61) are respectively connected to the A1 cavity and the B1 cavity through pipelines, and a first branch (611) with unidirectional conduction from the B1 cavity to the A1 cavity is connected in parallel with the first heat absorber (61). The two ends of the second heat absorber (62) are respectively connected to the A2 cavity and the B2 cavity through pipelines, and a second branch (621) with unidirectional conduction from the B2 cavity to the A2 cavity is connected in parallel with the second heat absorber (62). The heat dissipation cylinder (61), the heat insulation cylinder (51), the first heat absorber (61), the second heat absorber (62), and the connecting pipeline are filled with heat exchange working gas.

2. The heat-to-work conversion device according to claim 1, characterized in that, The sealing box includes a sealing cover (1) with an upper opening and a sealing plate (2) covering the opening of the sealing cover (1). The sealing plate (2) has a first through hole (21) and a second through hole (22). The output component (3) is fixedly installed in the sealed box, and the power generation device (33) is provided with a wire leading out to the outside of the sealed box; The heat dissipation cylinder (41) has an opening at one end, and the opening end of the heat dissipation cylinder (41) faces the first through hole (21) and is sealed to the sealing plate (2). The heat dissipation piston (42), the heat dissipation cylinder (41) and the sealing plate (2) form the A2 cavity. The heat dissipation piston rod (43) passes through the first through hole (21) and extends into the sealing box in a sliding seal manner. The insulated cylinder (51) has an opening at one end, the opening of the insulated cylinder (51) faces the second through hole (22) and is sealed to the sealing plate (2). The insulated piston (52), the insulated cylinder (51) and the sealing plate (2) form the B2 cavity. The insulated piston rod (53) passes through the second through hole (22) and extends into the sealing box in a sliding seal manner. The sealed box is filled with a heat exchange working gas.

3. The heat-to-work conversion device according to claim 2, characterized in that, The mounting bracket (31) is also equipped with a guide plate (36). The guide plate (36) is provided with a first guide hole and a second guide hole that are coaxial with the first through hole (21) and the second through hole (22), respectively. The heat dissipation piston rod (43) passes through the first guide hole, and the heat insulation piston rod (53) passes through the second guide hole.

4. The heat-to-work conversion device according to claim 1, characterized in that, The outer wall of the heat dissipation cylinder (41) is provided with a number of fin structures (411) for heat dissipation.

5. The heat-work conversion device according to claim 4, characterized in that, Both sides of the heat dissipation piston (42) are provided with a plurality of first fins (421) extending toward the end, and both ends of the internal cavity of the heat dissipation cylinder (41) are provided with a plurality of second fins (422) extending toward the heat dissipation piston (42); the first fins (421) on the same side of the heat dissipation piston (42) are interspersed in the intervals of the second fins (422) on the corresponding side.

6. The heat-work conversion device according to claim 1, characterized in that, A first check valve (612) is provided on the first branch (611), and the first check valve (612) is unidirectionally open from the B1 chamber to the A1 chamber; A second one-way valve (622) is provided on the second branch (621), and the second one-way valve (622) is unidirectionally open from the B2 chamber to the A2 chamber.

7. The heat-work conversion device according to claim 1, characterized in that, The heat exchange assembly also includes a first regenerator (7) and a second regenerator (8); The first regenerator (7) is installed on the pipeline connecting the first absorber (61) and the A1 cavity, and the second regenerator (8) is installed on the pipeline connecting the second absorber (62) and the A2 cavity.

8. The heat-to-work conversion device according to any one of claims 1 to 7, characterized in that, The phase angle of the second link (35) leads the phase angle of the first link (34) by 90°.

9. The heat-to-work conversion device according to any one of claims 1 to 7, characterized in that, The output assembly (3) also includes a flywheel (37) mounted on the end of the output shaft (32) away from the power generation device (33).

10. The heat-to-work conversion device according to any one of claims 1 to 7, characterized in that, At least one openable first working fluid supply port (101) is provided in the heat dissipation cylinder (41), the heat insulation cylinder (51), the first heat absorber (61), the second heat absorber (62) and the connecting pipeline.

11. The heat-to-work conversion device according to claim 2, characterized in that, The sealed housing is provided with a second working fluid supply port (102) that can be opened and closed.

12. The heat-to-work conversion device according to claim 11, characterized in that, It also includes a control device (10), a gas working medium supply device (9), and a pressure sensor (91). The gas working medium supply device (9) is connected to the second working medium supply port (102). The pressure sensor (91) is installed on the sealed box and is used to measure the pressure in the sealed box. The control device (10) is electrically connected to the gas working medium supply device (9) and the pressure sensor (91). A comparison pressure T0 is preset in the control device (10). The methods for regulating the pressure in the sealed enclosure include: The control device (10) controls the pressure sensor (81) to collect the real-time pressure T1 in the sealed box according to a set cycle; The control device (10) determines the magnitude of the real-time pressure T1 and the comparison pressure T0; If the real-time pressure T1 is greater than or equal to the comparison pressure T0, then maintain the current state; If the real-time pressure T1 is less than the comparison pressure T0, the control device (10) controls the gas working medium supply device (9) to supply heat exchange gas working medium to the sealed box until the real-time pressure T1 is greater than or equal to the comparison pressure T0.

13. A waste heat recovery system for an internal combustion engine, characterized in that, It includes an internal combustion engine and a heat-to-work conversion device as described in any one of claims 1 to 12, wherein the exhaust port of the internal combustion engine is connected to the heat source inlet (601) of the heat exchanger (6) of the heat-to-work conversion device.

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