Embedded heat pipe automotive thermoelectric generator and its structural optimization method

Abstract

This invention belongs to the field of automotive exhaust waste heat recovery technology, and particularly relates to an automotive thermoelectric generator with embedded heat pipes and its structural optimization method. The device includes: a heat exchanger, a collector, several heat spreaders, and a thermoelectric generator module. The heat spreaders have heat pipes on the side facing the heat exchanger; the collector has a spiderweb-like cross-section; after exhaust gas from the exhaust pipe enters the heat exchanger, the collector transfers the heat from the exhaust gas to the heat spreaders through the heat pipes. The heat spreaders heat the attachment end of the thermoelectric generator module to the heat spreader, causing the thermoelectric generator module to generate electricity. Utilizing the high heat transfer efficiency of the heat pipes, heat from the exhaust gas is conducted to the hot end surface of the thermoelectric generator module, increasing the temperature difference between the two ends of the module and improving the recovery rate of exhaust waste heat. The embedded heat pipe arrangement allows for the placement of more thermoelectric generator modules within a limited space, increasing the total output power of the device.

Description

Technical Field

[0001] This invention belongs to the field of automotive exhaust waste heat recovery technology, and particularly relates to an automotive thermoelectric generator with an embedded heat pipe and its structural optimization method. Background Technology

[0002] Energy conservation, environmental protection, and low carbon emissions have become global themes of exploration. With the proposal of "carbon peaking and carbon neutrality" goals and the emergence of the problem of low energy utilization in automobiles, researchers have gradually explored the recycling and treatment of vehicle exhaust and the utilization of waste. In traditional internal combustion engine vehicles, about 30% of the energy released by the combustion of petroleum fuel is utilized to convert into the kinetic energy of the vehicle, while about 40% of the energy is emitted into the atmosphere with the exhaust. This wastes most of the energy and causes serious environmental pollution.

[0003] Thermoelectric power generation is a novel, green, and environmentally friendly energy technology that utilizes the Seebeck effect to directly convert heat energy into electrical energy. It involves converting low-grade waste heat energy from exhaust gases into high-grade electrical energy, which can then be stored in car batteries or used for vehicle electrical systems. Specifically, the thermoelectric power generation device uses P-type and N-type semiconductors as thermoelectric materials. These two types of semiconductors are connected to form a PN thermoelectric arm. If a temperature difference exists between the two ends of the PN thermoelectric arm, holes in the P-type semiconductor move from the hot end to the cold end, and electrons in the N-type semiconductor move from the hot end to the cold end, thus generating an electric current.

[0004] However, although traditional thermoelectric power generation technology can convert heat energy into electrical energy, the high speed of automobile exhaust means that most of the heat in the exhaust cannot be fully utilized before it is discharged, resulting in low thermoelectric conversion efficiency and poor practical performance.

[0005] Therefore, there is an urgent need to design an automotive thermoelectric power generation device with an embedded heat pipe to solve the technical problem that most of the heat in the exhaust gas cannot be fully utilized before being discharged, resulting in low thermoelectric conversion efficiency and poor actual use effect.

[0006] This significantly improves thermoelectric conversion efficiency and enables the effective utilization of low-grade heat energy in automobile exhaust.

[0007] It should be noted that the information disclosed in this background section is only for understanding the background technology of this application concept, and therefore may include information that does not constitute prior art. Summary of the Invention

[0008] This disclosure provides at least one automotive thermoelectric generator with an embedded heat pipe and a method for optimizing its structure.

[0009] In a first aspect, embodiments of this disclosure provide an automotive thermoelectric generator with an embedded heat pipe, comprising: a heat exchanger, which is cylindrical and one end is connected to an exhaust pipe; A solar collector, which is installed inside a heat exchanger; Several heat exchange blocks are arranged circumferentially on the outside of the heat exchanger; Thermoelectric power generation module, which is attached to one side of the heat exchange block; The heat exchanger block has a heat pipe on the side facing the heat exchanger, with one end of the heat pipe inserted into the heat exchanger and connected to the heat collector. The cross-section of the solar collector is spider web-like, and its length direction is parallel to that of the heat exchanger. Furthermore, after the exhaust gas in the exhaust pipe enters the heat exchanger, it passes through the gap between the collectors. The collector transfers the heat of the exhaust gas to the heat exchange block through the heat pipe, and heats the thermoelectric power generation module attached to the heat exchange block through the heat exchange block, so that the thermoelectric power generation module generates electricity.

[0010] In one optional embodiment, the solar collector includes a plurality of solar collector ribs, which are evenly arranged circumferentially. Several fins are arranged between two adjacent heat collection ribs. The two ends of the fins are connected to the heat collection ribs respectively, and the fins are arranged at equal intervals from the inside to the outside along the radial direction. The heat-collecting ribs and fins are arranged alternately along the circumference to form a closed loop.

[0011] In one alternative embodiment, the collector has a hollow flow channel at its center, and the heat collection ribs are circumferentially distributed around the hollow flow channel. The heat collecting frame has several embedding holes along its thickness direction, and the heat pipe is inserted into the heat collecting frame along the embedding holes.

[0012] In one optional implementation, a radiator is provided on the side of the thermoelectric power generation module away from the heat exchange block; The gap between the radiator and the heat exchanger is set; The heat exchange block and the radiator form a hot end and a cold end on both sides of the thermoelectric power generation module, respectively, so that the thermoelectric power generation module can generate electrical energy.

[0013] In one alternative embodiment, the radiator has a flow channel inside, the path of which covers the heat exchange surface of the radiator. The side wall of the radiator has a water inlet and a water outlet.

[0014] In one alternative embodiment, both the collector and the heat exchanger are regular hexagonal prism structures.

[0015] In one optional embodiment, the thermoelectric power generation module includes several P-type thermoelectric arms, N-type thermoelectric arms, metal electrode plates, and two ceramic substrates. The P-type thermoelectric arms and N-type thermoelectric arms are arranged in an array, and the P-type thermoelectric arms and N-type thermoelectric arms are arranged alternately. The metal electrode plate is installed between two adjacent P-type thermoelectric arms and N-type thermoelectric arms; The two ceramic substrates are located on both sides of the P-type thermoelectric arm and the N-type thermoelectric arm, respectively, and are attached to the metal electrode plate.

[0016] In one optional embodiment, the heat exchanger is equipped with an inlet end cap and an outlet end cap at its front and rear ends, respectively.

[0017] Secondly, this disclosure also provides a method for optimizing the automotive thermoelectric power generation structure using an embedded heat pipe. This method is performed using the automotive thermoelectric power generation device with an embedded heat pipe as described above. The specific steps of the method for optimizing the automotive thermoelectric power generation structure with an embedded heat pipe include: A net power model is established to analyze the output performance of an automotive thermoelectric generator with integrated heat pipes, thereby determining the optimal number of heat pipes. N The length of the heat pipe embedded heat exchanger is L4-H2-D3; in, , Net power of the thermoelectric generator; Total output power of the thermoelectric generator. ,in The output voltage of each thermoelectric generator module, p i For the first i The output power of each thermoelectric power generation module This refers to the number of thermoelectric power generation modules in the device. Internal resistance of a single thermoelectric generator module; back pressure loss of the thermoelectric generator. ,in The pressure difference between the inlet of the air intake cap and the outlet of the air outlet cap (8) is the pressure difference between the inlet of the air intake cap and the outlet of the air outlet cap (8). The mass flow rate of the exhaust gas. To simulate exhaust gas density, hot air is used as the exhaust heat source to provide the hot-end operating temperature for the thermoelectric power generation system during simulation analysis; the density is based on air density. The pump power loss of the thermoelectric power generation device is also considered. ,in The flow rate of the cooling water. This is the cross-sectional area of ​​the cooling water inlet. This represents the pressure difference between the cooling water inlet and outlet.

[0018] In one optional implementation, the structure under different parameters is simulated using COMSOL multiphysics simulation software to obtain the corresponding output parameters. The boundary conditions are as follows: inlet temperature T of the air intake end cap. h Inlet flow velocity V0, outlet pressure is standard atmospheric pressure, cooling medium is water, inlet temperature TW The flow velocity is V W The outlet pressure is standard atmospheric pressure, and the current boundary condition is that the thermoelectric power generation module is connected to an external virtual resistor in the COMSOL multiphysics simulation software, with the external circuit virtual resistance value being R. L .

[0019] The beneficial effects of this invention are that by utilizing the high heat transfer efficiency of heat pipes, the heat in the exhaust gas is conducted to the hot end surface of the thermoelectric power generation module, thereby increasing the temperature difference between the two ends of the thermoelectric power generation module and improving the recovery and utilization rate of waste heat from the exhaust gas by the thermoelectric power generation device; the embedded arrangement of heat pipes allows the device to arrange more thermoelectric power generation modules in a limited space, thereby increasing the total output power of the device.

[0020] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention are realized and obtained in accordance with the structures particularly pointed out in the description, claims and drawings.

[0021] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0022] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0023] Figure 1 A schematic diagram of an automotive thermoelectric generator with an embedded heat pipe provided in an embodiment of this disclosure; Figure 2 A front view of an automotive thermoelectric generator with an embedded heat pipe provided in an embodiment of this disclosure; Figure 3 This is a schematic diagram of a heat exchanger structure provided in an embodiment of the present disclosure; Figure 4 This is a schematic diagram of a solar collector structure provided in an embodiment of the present disclosure; Figure 5 for Figure 4 A magnified view of a portion of point A in the middle; Figure 6 A schematic diagram of the structure and distribution of a heat pipe and a heat-spreading aluminum block is provided for an embodiment of this disclosure; Figure 7This is a schematic diagram of a thermoelectric power generation module structure provided in an embodiment of the present disclosure; Figure 8 This is a schematic diagram of a water-cooled radiator structure provided in an embodiment of this disclosure.

[0024] In the picture: 1. Heat exchanger; 2. Heat collector; 3. Heat pipe; 4. Heat spreader; 5. Thermoelectric generator module; 6. Radiator; 7. Inlet end cap; 8. Outlet end cap; 9. Embedded hole; 10. Fins; 11. Hollow flow channel; 12. Heat collector rib; 13. P-type thermoelectric arm; 14. N-type thermoelectric arm; 15. Metal electrode plate; 16. Ceramic substrate; 17. Flow channel. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] Research has revealed that thermoelectric power generation is a novel, green, and environmentally friendly energy technology that utilizes the Seebeck effect to directly convert heat energy into electrical energy. This involves converting low-grade waste heat energy from exhaust gases into high-grade electrical energy, which can then be stored in car batteries or used for vehicle electrical systems. Specifically, the thermoelectric power generation device uses P-type and N-type semiconductors as thermoelectric materials. These two types of semiconductors are connected to form a PN thermoelectric arm. If a temperature difference exists between the two ends of the PN thermoelectric arm, holes in the P-type semiconductor move from the hot end to the cold end, and electrons in the N-type semiconductor move from the hot end to the cold end, thus generating an electric current.

[0027] However, although traditional thermoelectric power generation technology can convert heat energy into electrical energy, the high speed of automobile exhaust means that most of the heat in the exhaust cannot be fully utilized before it is discharged, resulting in low thermoelectric conversion efficiency and poor practical performance.

[0028] Therefore, there is an urgent need to design an automotive thermoelectric power generation device with an embedded heat pipe to solve the technical problem that most of the heat in the exhaust gas cannot be fully utilized before being discharged, resulting in low thermoelectric conversion efficiency and poor actual use effect.

[0029] The shortcomings of the above solutions are the result of the inventor's practical experience and careful research. Therefore, the discovery process of the above problems and the solutions proposed in this disclosure below should be considered as the inventor's contribution to this disclosure.

[0030] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the embodiments and features described below can be combined with each other. Furthermore, in the accompanying drawings, the thickness of components may be exaggerated or reduced for the purpose of effectively describing the technical content.

[0031] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0032] Based on the above research, and referring to Figure 1 and Figure 2 This disclosure provides an automotive thermoelectric generator with an embedded heat pipe, comprising: a heat exchanger 1, a collector 2, a heat pipe 3, several heat spreaders 4, and a thermoelectric power generation module 5. The heat exchanger 1 is cylindrical, hollow inside, and open at both ends. One end of the heat exchanger 1 is adapted to be installed on an exhaust pipe so that high-temperature exhaust gas is introduced into the heat exchanger 1 when the vehicle exhausts. The collector 2 is installed inside the heat exchanger 1 and is adapted to absorb heat from the exhaust gas while ensuring that the exhaust gas can pass smoothly through the collector 2. Several heat spreaders 4 are arranged circumferentially on the outside of the heat exchanger 1, and the heat pipe 3 is installed between the heat spreaders 4 and the heat exchanger 1. Specifically, one end of the heat pipe 3 is inserted into the heat exchanger 1 and connected to the collector 2, and the other end of the heat pipe 3 is inserted into the heat spreader 4, thus making the heat pipe 3 a heat-conducting mechanism, i.e., the heat absorbed by the collector 2 is conducted to the heat spreader 4 through the heat pipe 3. Meanwhile, the heat exchanger 4 itself is a flat plate structure. After heat is introduced into the heat exchanger 4 through the heat pipe 3, it can spread along the surface of the plate, thus forming two heating surfaces (corresponding to the two larger planes of the heat exchanger 4). Thermoelectric power generation module 5 is attached to one side of the heat exchanger 4, that is, attached to the heating surface of the heat exchanger 4. Optionally, one thermoelectric power generation module 5 can be attached to each of the two heating surfaces of one heat exchanger 4. The side of the thermoelectric power generation module 5 that is in contact with the heating surface of the heat exchanger 4 continuously receives heat conducted by the heat exchanger 4, thus becoming the hot end. The side of the thermoelectric power generation module 5 that is away from the heat exchanger 4 is not heated, thus creating a relative temperature difference, becoming the cold end. The thermoelectric power generation module 5 utilizes the Seebeck effect to generate electrical energy from the heat energy under the action of the hot and cold ends.

[0033] Reference Figure 1 In at least one embodiment, both the collector 2 and the heat exchanger 1 are regular hexagonal prism structures. The collector 2 is fitted to the inner wall of the heat exchanger 1 from each of its inner corners to ensure optimal heat transfer efficiency. Simultaneously, six heat equalization blocks 4 are also arranged axially along the heat exchanger 1, with each heat equalization block corresponding to one side of the heat exchanger 1.

[0034] Reference Figure 2In some embodiments, an inlet end cover 7 and an outlet end cover 8 are respectively installed at the front and rear ends of the heat exchanger 1. The front ends of the inlet end cover 7 and the outlet end cover 8 are hollow cylinders, and the rear ends are hollow frustums, corresponding to the heat exchanger 1. The radius of the front end opening of the inlet end cover 7 and the outlet end cover 8 is R2, and the radius of the rear frustum is R3. The inlet end cover 7 and the outlet end cover 8 can serve as transition components for connecting to exhaust pipes and other subsequent optional components.

[0035] Reference Figure 4 In at least one embodiment, the heat collector 2 includes a plurality of heat collection ribs 12, which are uniformly arranged circumferentially. A plurality of fins 10 are disposed between adjacent heat collection ribs 12, with both ends of the fins 10 connected to the heat collection ribs 12 respectively, and the fins 10 are arranged radially from the inside out at equal intervals. The heat collection ribs 12 and fins 10 are arranged in a staggered manner along the circumferential direction, forming a closed loop. This arrangement creates a spiderweb-like structure between the fins 10 and the heat collection ribs 12, and the length directions of the fins 10 and the heat collection ribs 12 are parallel to the length direction of the heat exchanger 1, ensuring that, under smooth exhaust gas flow, the heat from the exhaust gas is absorbed by multiple layers of fins 10 and conducted to the heat collection ribs 12.

[0036] Reference Figure 3 and Figure 4 In at least one embodiment, the collector 2 has a hollow flow channel 11 at its center, and heat collection ribs 12 are circumferentially distributed around the hollow flow channel 11, with the hollow flow channel 11 handling the main exhaust gas. Furthermore, the heat collection ribs 12 have several embedding holes 9 along their thickness direction. Simultaneously, the heat exchanger 1 also has embedding holes 9 at corresponding positions on the heat collection ribs 12, and the heat pipe 3 is inserted into the heat collection ribs 12 along the embedding holes 9. Exhaust gas passing through the hollow flow channel 11 can also directly transfer heat to the heat collection ribs 12 and conduct it to the heat pipe 3.

[0037] Reference Figure 2 and Figure 6 In at least one embodiment, the heat spreader 4 is rectangular, with a length of L1, a width of W1, and a height of H2.

[0038] Reference Figure 4 In at least one embodiment, the heat collection rib 12 has a length of L3, a width of W2, and a height of H1.

[0039] Reference Figure 5 In at least one embodiment, the thickness of the fin 10 is δ1, and the spacing between the inner and outer fins 10 is D1. Optionally, the number of fins 10 between the two heat collection ribs 12 is 10.

[0040] Reference Figure 2In at least one embodiment, the distance between the heat exchanger block 4 and the heat exchanger 1 is D3, thereby avoiding direct heat transfer between the heat exchanger 1 and the heat exchanger block 4, which would cause heat to concentrate on the side of the heat exchanger block 4 facing the heat exchanger 1, resulting in uneven temperature distribution of the heat exchanger block 4.

[0041] Reference Figure 6 In at least one embodiment, the heat pipe 3 is a cylindrical structure with a length of L4 and a diameter of d1, and the length of the heat pipe 3 embedded in the heat spreader 4 is H2. Therefore, the length of the heat pipe 3 embedded in the heat collector rib 12 is L4-H2-D3. In addition, the distance between two adjacent heat pipes 3 on the same side of the heat exchanger 1 is D2.

[0042] Reference Figure 1 and Figure 2 In at least one embodiment, to further increase the relative temperature difference between the hot and cold ends of the thermoelectric generator module, a radiator 6 is provided on the side of the thermoelectric generator module 5 away from the heat spreader 4. The radiator 6 is a water-cooled radiator 6, and its interior is suitable for the flow of coolant. The radiator 6 is spaced apart from the heat exchanger 1. The heat spreader 4 and the radiator 6 form the hot end and cold end on both sides of the thermoelectric generator module 5, respectively, so that the thermoelectric generator module 5 can generate electrical energy.

[0043] Reference Figure 8 In at least one embodiment, the radiator 6 has a flow channel 17 inside, the path of which covers the heat exchange surface of the radiator 6. Specifically, with Figure 8 For example, the flow channel 17 has a continuously bent and rotating M-shaped structure to cover the heat exchange surface of the radiator 6 as much as possible, ensuring uniform heat dissipation and cooling. The side wall of the radiator 6 has an inlet and a drain for the flow of coolant. In some embodiments, the inlets and drains of each radiator 6 can be connected in series through pipes to achieve efficient and rapid heat exchange, and a main inlet and main drain can be installed on any one of the radiators 6 to connect to an external coolant source. The rated length of the radiator 6 is L7, the width is W3, and the height is H3. The diameter of the flow channel 17 is d2, and the gap between the radiator 6 and the heat exchanger 1 is also D3 to avoid heat exchange between the radiator 6 and the heat exchanger 1.

[0044] Reference Figure 7In at least one embodiment, the thermoelectric power generation module 5 includes a plurality of P-type thermoelectric arms 13, N-type thermoelectric arms 14, metal electrode plates 15, and two ceramic substrates 16. The P-type thermoelectric arms 13 and N-type thermoelectric arms 14 are arranged in an array and are staggered. The metal electrode plates 15 are installed between adjacent P-type thermoelectric arms 13 and N-type thermoelectric arms 14. The two ceramic substrates 16 are located on both sides of the P-type thermoelectric arms 13 and N-type thermoelectric arms 14, and are attached to the metal electrode plates 15. Preferably, there are 127 P-type thermoelectric arms 13, 127 N-type thermoelectric arms 14, and 254 metal electrode plates 15. The ceramic substrates 16 are square with a length of L5, and the metal electrode plates 15 have a length of L6.

[0045] Furthermore, this disclosure also provides a method for optimizing the automotive thermoelectric power generation structure using an embedded heat pipe. This method is implemented using the automotive thermoelectric power generation device with an embedded heat pipe as described above. The specific steps of the method for optimizing the automotive thermoelectric power generation structure with an embedded heat pipe include: A net power model is established to analyze the output performance of the automotive thermoelectric generator with integrated heat pipe 3, and then the optimal number of heat pipes 3 N and the length of heat pipe 3 embedded in heat exchanger 11 L4-H2-D3 are determined. in, , Net power of the thermoelectric generator; Total output power of the thermoelectric generator. ,in The output voltage of each thermoelectric generator module, p i For the first i The output power of each thermoelectric power generation module This refers to the number of thermoelectric power generation modules in the device. Internal resistance of a single thermoelectric generator module; back pressure loss of the thermoelectric generator. ,in The pressure difference between the inlet of the air intake cap and the outlet of the air outlet cap (8) is the pressure difference between the inlet of the air intake cap and the outlet of the air outlet cap (8). The mass flow rate of the exhaust gas. To simulate exhaust gas density, hot air is used as the exhaust heat source to provide the hot-end operating temperature for the thermoelectric power generation system during simulation analysis; the density is based on air density. The pump power loss of the thermoelectric power generation device is also considered. ,in The flow rate of the cooling water. This is the cross-sectional area of ​​the cooling water inlet. This represents the pressure difference between the cooling water inlet and outlet.

[0046] In one optional implementation, the structure under different parameters is simulated using COMSOL multiphysics simulation software to obtain the corresponding output parameters. The boundary conditions are as follows: inlet temperature T of the air inlet end cap 7. h Inlet flow velocity V0, outlet pressure is standard atmospheric pressure, cooling medium is water, inlet temperature T W The flow velocity is V W The outlet pressure is standard atmospheric pressure, and the current boundary condition is that the thermoelectric power generation module 5 is connected to an external virtual resistor in the COMSOL multiphysics simulation software, with the external circuit virtual resistance value being R. L .

[0047] At least one embodiment of the automotive thermoelectric generator with embedded heat pipes utilizes the high heat transfer efficiency of the heat pipes 3 to not only increase the temperature difference between the two ends of the thermoelectric generator module 5, but also allows for the arrangement of more thermoelectric generator modules 5 within a limited space by embedding them into the surface of the vertical heat exchanger 1, thereby increasing the total output power of the device. To maximize the gain brought by the heat pipes 3, the number of heat pipes 3 and the embedding length of the heat pipes 3 are optimized.

[0048] The following application examples illustrate this in detail: The above scheme was applied to the automotive thermoelectric generator, and the geometric parameters were set as shown in Table 1. The boundary conditions for the COMSOL simulation were shown in Table 2.

[0049] Table 1 Geometric parameters of automotive thermoelectric generator Table 2 Boundary conditions for COMSOL simulation Using COMSOL multiphysics simulation software, the number of heat pipes 3 on each side of heat exchanger 1 was simulated as N=5, and the embedding length of heat pipe 3 was L=5mm, 10mm, 15mm, 20mm, 25mm and 30mm respectively. The optimal embedding length was determined. Based on this, the number of heat pipes 3 was gradually increased from 2 to 8. The output power of each model is shown in Table 3 and Table 4.

[0050] Table 3 Output power at different heat pipe embedding lengths As shown in the table above, the total power increases with the increase of the heat pipe 3 embedding length, and the increase in total power continuously rises with the increase of the heat pipe 3 embedding length. The back pressure power loss also increases with the increase of the heat pipe 3 embedding length, but the pump power loss is small due to the simple flow channel and can be basically ignored. Although the power loss continuously increases with the increase of the heat pipe 3 embedding length, its net power still increases. In the six simulations, the maximum power was reached when the heat pipe 3 embedding length L=30mm.

[0051] Table 4 Output power with different numbers of heat pipes As shown in the table above, as the number of heat pipes increases, the total power increases and then stabilizes, reaching a saturation state. At this point, the back pressure power loss and pump power loss remain stable. When the number of heat pipes reaches 6, the system net power reaches its maximum of 154.2W. At this point, a heat pipe embedding length of 30mm and a number of 6 are the optimal choices.

[0052] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. Furthermore, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Based on the above-described ideal embodiments of the present invention, and through the above description, those skilled in the art can make various changes and modifications without departing from the technical spirit of the disclosed embodiments. The technical scope of the embodiments of this disclosure is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A thermoelectric generator for automobiles with an embedded heat pipe, characterized in that, include: The heat exchanger (1) is cylindrical and one end is connected to the exhaust pipe; The collector (2) is installed inside the heat exchanger (1); Several heat exchange blocks (4) are arranged circumferentially on the outside of the heat exchanger (1); Thermoelectric module (5) is attached to one side of heat spreader (4); The heat exchange block (4) has a heat pipe (3) on the side facing the heat exchanger (1), and one end of the heat pipe (3) is inserted into the heat exchanger (1) and connected to the collector (2). The cross-section of the collector (2) is spider web-shaped, and its length direction is parallel to that of the heat exchanger (1); Furthermore, after the exhaust gas in the exhaust pipe enters the heat exchanger (1), it passes through the gap between the collectors (2). The collectors (2) transfer the heat of the exhaust gas to the heat exchange block (4) through the heat pipe (3), and heat the thermoelectric power generation module (5) and the attachment end of the heat exchange block (4) through the heat exchange block (4) so ​​that the thermoelectric power generation module (5) generates electricity.

2. The automotive thermoelectric generator with embedded heat pipe as described in claim 1, characterized in that, The collector (2) includes a plurality of heat collection ribs (12), which are evenly arranged circumferentially; Several fins (10) are provided between two adjacent heat collection ribs (12). The two ends of the fins (10) are connected to the heat collection ribs (12) respectively, and each fin (10) is arranged at equal intervals from the inside to the outside in the radial direction. The heat-collecting ribs (12) and fins (10) are arranged alternately along the circumference to form a closed loop.

3. The automotive thermoelectric generator with embedded heat pipe as described in claim 2, characterized in that, The collector (2) has a hollow flow channel (11) at its center, and the heat collection ribs (12) are circumferentially distributed around the hollow flow channel (11); The heat collecting rib (12) has several embedding holes (9) along its thickness direction, and the heat pipe (3) is inserted into the heat collecting rib (12) along the embedding holes (9).

4. The automotive thermoelectric generator with embedded heat pipe as described in claim 1, characterized in that, The thermoelectric power generation module (5) is provided with a radiator (6) on the side away from the heat exchange block (4). The radiator (6) and the heat exchanger (1) are spaced apart; The heat exchange block (4) and the radiator (6) form a hot end and a cold end on both sides of the thermoelectric power generation module (5) respectively, so that the thermoelectric power generation module (5) generates electrical energy.

5. The automotive thermoelectric generator with an embedded heat pipe as described in claim 4, characterized in that, The radiator (6) has a flow channel (17) inside, and the path of the flow channel (17) covers the heat exchange surface of the radiator (6). The side wall of the radiator (6) has an inlet and an outlet.

6. The automotive thermoelectric generator with an embedded heat pipe as described in claim 1, characterized in that, Both the collector (2) and the heat exchanger (1) are regular hexagonal prism structures.

7. The automotive thermoelectric generator with an embedded heat pipe as described in claim 1, characterized in that, The thermoelectric power generation module (5) includes several P-type thermoelectric arms (13), N-type thermoelectric arms (14), metal electrode plates (15) and two ceramic substrates (16). The P-type thermoelectric arm (13) and N-type thermoelectric arm (14) are arranged in an array, and the P-type thermoelectric arm (13) and N-type thermoelectric arm (14) are staggered. The metal electrode plate (15) is installed between two adjacent P-type thermoelectric arms (13) and N-type thermoelectric arms (14); The two ceramic substrates (16) are located on both sides of the P-type thermoelectric arm (13) and the N-type thermoelectric arm (14), respectively, and are attached to the metal electrode plate (15).

8. The automotive thermoelectric generator with an embedded heat pipe as described in claim 1, characterized in that, The heat exchanger (1) is equipped with an inlet end cover and an outlet end cover (8) at its front and rear ends, respectively.

9. A method for optimizing the automotive thermoelectric power generation structure using an embedded heat pipe, wherein the method is performed using an automotive thermoelectric power generation device with an embedded heat pipe as described in any one of claims 1-7, characterized in that, The optimization method for the automotive thermoelectric power generation structure using embedded heat pipes specifically includes the following steps: A net power model was established to analyze the output performance of the automotive thermoelectric generator with integrated heat pipe (3), and then the optimal number of heat pipes N and the length of heat pipe embedded heat exchanger (1) L4-H2-D3 were determined. in, , Net power of the thermoelectric generator; Total output power of the thermoelectric generator. ,in The output voltage of each thermoelectric generator module, p i For the first i The output power of each thermoelectric power generation module This refers to the number of thermoelectric power generation modules in the device. Internal resistance of a single thermoelectric generator module; back pressure loss of the thermoelectric generator. ,in The pressure difference between the inlet of the air intake cap and the outlet of the air outlet cap (8) is the pressure difference between the inlet of the air intake cap and the outlet of the air outlet cap (8). The mass flow rate of the exhaust gas. To simulate exhaust gas density, hot air is used as the exhaust heat source to provide the hot-end operating temperature for the thermoelectric power generation system during simulation analysis; the density is based on air density. The pump power loss of the thermoelectric power generation device is also considered. ,in The flow rate of the cooling water. This is the cross-sectional area of ​​the cooling water inlet. This represents the pressure difference between the cooling water inlet and outlet.

10. The method for optimizing the automotive thermoelectric power generation structure with embedded heat pipes as described in claim 9, characterized in that, The structure under different parameters was simulated using COMSOL multiphysics simulation software to obtain the corresponding output parameters. The boundary conditions are as follows: inlet end cap (7) inlet temperature T h Inlet flow velocity V0, outlet pressure is standard atmospheric pressure, cooling medium is water, inlet temperature T W The flow velocity is V W The outlet pressure is standard atmospheric pressure, and the current boundary condition is that the thermoelectric power generation module (5) is connected to an external virtual resistor in the COMSOL multiphysics simulation software, and the resistance value of the external circuit virtual resistor is R. L .

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