CN103644016B - The finned automobile exhaust thermoelectric generating device of the straight plate of cylindrical shell - Google Patents

Abstract

The invention discloses a cylindrical shell straight plate fin type automobile exhaust thermoelectric power generation device, wherein two semi-cylindrical shells with identical structures are butted on the exhaust pipe and fixed by fastening bolts and welding; the heat conducting fins It is installed on the semi-cylindrical shell through the assembly groove reserved on it, and a certain number of thermoelectric power generation modules are closely attached on both sides of the fin; a group of thermoelectric power generation modules on each side of the fin is arranged with a separate rectangular cross-section thin wall The cooling pipe is fixed and installed through the supporting discs at both ends with the fastening device; heat insulating gaskets are installed at different positions of the supporting discs to reduce the influence on the temperature of the cooling liquid in the cooling channel. The cylindrical shell, straight plate and fin type automobile exhaust thermoelectric power generation device has the advantages of simple and compact structure, high working reliability, and good heat conduction effect. Gas back pressure, suitable for large-scale promotion and application.

Description

Cylindrical Shell Straight Plate Fin Type Automobile Exhaust Thermoelectric Power Generation Device

technical field

The invention relates to the technical field of thermoelectric power generation, and belongs to a novel form of engine waste heat recovery and utilization, in particular to a cylindrical shell straight plate fin type automobile exhaust thermoelectric power generation device.

Background technique

The automobile industry accounts for a very high proportion in my country's national economy. Since the beginning of the 21st century, the automobile industry has developed rapidly, and the corresponding energy required by automobiles has also increased day by day. The development of automobile energy-saving technology has attracted much attention. At present, the conversion efficiency of the energy generated by fuel combustion in automobile engines is only about 40%, which means that more than 60% of the energy in the fuel is not effectively utilized and is discharged into the atmosphere. In this 60% of the energy, the exhaust gas from the engine takes away about 30% to 45% of the total energy, and about 30% of the energy is used for cooling, most of which are in the form of waste heat. Distributed in the air, a large amount of energy is inevitably wasted, causing very serious air pollution. Thermoelectric power generation technology uses the Seebeck effect to directly convert heat energy into electrical energy. It has the advantages of no moving parts, no noise, no pollution, reliable operation, and long service life. It has been widely used in the field of industrial waste heat recovery, and in engine waste heat recovery. , thermoelectric power generation technology is also considered to be a new technology that has the potential to replace traditional automobile generators. The thermoelectric power generation system can not only effectively recover the waste heat of the engine, reduce energy waste and discharge harmful substances, but also store the converted electric energy in the vehicle battery or other energy storage devices through the external circuit for the use of automotive electronic equipment, effectively Improve the fuel efficiency of the car.

Contents of the invention

Aiming at the deficiencies of the traditional automobile exhaust pipe thermoelectric power generation device, such as large changes in the exhaust structure, single power generation, insufficient contact of the power generation device, and influence on the exhaust back pressure of the engine, a cylindrical shell straight plate fin type automobile exhaust is proposed. Gas thermoelectric power generation device. The device can be arranged between the automobile exhaust catalytic converter and the muffler, and effectively recovers the waste heat of the engine to convert electric energy. The two semi-cylindrical shells directly contact the exhaust pipe and are connected by fastening bolts to support the heat conducting fins, the thermoelectric power generation module, and the cooling pipe support disc, etc. The semi-cylindrical shell is in direct contact with the exhaust pipe for heat conduction, which avoids the structural modification of the exhaust pipe to adapt to the size of the thermoelectric power generation module, and will not have any impact on the exhaust back pressure of the engine. The cooling pipe introduces the coolant flow through the branch of the engine cooling system to cool the cold end of the thermoelectric power generation module. The cooling pipe is designed as a flat rectangular cross-section channel with uniform specifications and convenient interfaces. A cooling pipe support disc is arranged at both ends of the semi-cylindrical shell and is connected with the semi-cylindrical shell by bolts, so that the structure of the whole thermoelectric power generation device is stable and reliable.

In order to further achieve the purpose of the present invention and improve the efficiency of thermoelectric power generation, the semi-cylindrical shell directly in contact with the exhaust pipe adopts a stainless steel structure, which has stable heat conduction and reliable structure, and can meet the requirements of the exhaust temperature for the heat exchanger (automotive three-way catalysis The exhaust temperature near the converter is about 770K). The heat conduction fins are made of aluminum alloy, which has a good heat conduction effect, can provide a higher temperature for the hot end of the thermoelectric power generation module, and increase the temperature difference between the two ends of the thermoelectric power generation module to increase the power generation. Apply a certain amount of thermal conductive silicone grease between the thermal fins and the hot end of the thermoelectric power generation module to reduce the contact thermal resistance caused by the rough surface and further improve the thermal conductivity. The cooling pipe is also made of aluminum alloy, and its structure adopts straight channel and thin-walled rectangular section, which can be directly processed and welded by aluminum alloy plate, which is convenient for production. The aluminum alloy cooling pipe is fixed with the fastening device through the supporting discs at both ends and is in close contact with the thermoelectric power generation module, and forms a certain pre-tightening force, so that the thermoelectric power generation module and the heat conduction fins, as well as the thermoelectric power generation module and the cooling pipe are tightly connected. fit. Between the support disc and the exhaust pipe and around the connecting bolts between the support disc and the semi-cylindrical shell, heat insulating gaskets made of heat insulating materials are arranged to minimize the influence of the support disc on the temperature of the coolant in the cooling pipe due to the heating of the support disc.

The advantages of the present invention are:

(1) This device has high heat conduction efficiency and relatively small thermal resistance. Compared with the traditional automobile exhaust pipe thermoelectric power generation device, it improves the recovery efficiency of exhaust waste heat and is suitable for large-scale mass production.

(2) The structure of the device is compact and simple, no modification of the exhaust pipe is required, the installation and maintenance are convenient, and the work reliability is high.

Description of drawings

Fig. 1 is the structural representation of automobile exhaust thermoelectric power generation device of the present invention;

Fig. 2 is the left view of Fig. 1;

FIG. 3 is a sectional view along line A-A of FIG. 1 .

In the picture:

1. Exhaust pipe; 2. Support disc A; 3. Fastening device; 4. Cooling pipe; 5. Assembly boss;

6. Fastening bolts; 7. Heat conduction fins; 8. Support disc B; 9. Thermoelectric power generation module; 10. Semi-cylindrical shell;

11. Connecting bolts; 12. Insulation washer A; 13. Insulation washer B.

detailed description

The present invention will be further described below in conjunction with the accompanying drawings.

The present invention provides a cylindrical shell straight plate fin type automobile exhaust thermoelectric power generation device, as shown in Fig. Disc A2, support disc B8, insulating washer A12 and insulating washer B13.

The device provided by the invention is located on the exhaust pipe 1 between the three-way catalytic converter and the muffler of the automobile. Referring to Figures 1 and 3, two identical semi-cylindrical shells 10 are tightly connected through the fastening bolts 6 on the assembly boss 5 (preferably, 11 fastening bolts 6 are set on one side of the assembly boss, A total of 22 fastening bolts 6) on both sides, and the semi-cylindrical shell 10 can also be welded on the exhaust pipe 1 by welding to improve its structural stability and ensure the connection between the two semi-cylindrical shells 10 and the exhaust pipe 1. close contact between. Install the heat conduction fins 7 on the fitting grooves of the semi-cylindrical shell 10 . On the surface of the semi-cylindrical shell 10, a number of assembly grooves with the same specifications and evenly distributed along the circumferential direction are reserved, the length of the assembly groove is equal to the axial length of the semi-cylindrical shell 10, and the axis of the assembly groove is parallel to the axis of the cylindrical shell; the groove of the assembly groove The depth should not exceed 20% of the axial thickness of the semi-cylindrical shell 10. The number of heat conduction fins 7 can be adjusted arbitrarily within the number of reserved assembly slots to meet different power generation requirements. As shown in Figure 3, 8 separate heat conduction fins are installed. fin7. Apply a certain amount of heat-conducting silicone grease in the assembly groove and the contact surface between the heat-conducting fin 7 and the assembly groove to improve the heat-conducting capacity. Both ends of the heat-conducting fin 7 and the two ends of the assembly groove are reserved at the same positions for connecting bolt holes, and fastened. Bolt on. The heat conduction fins 7 may also be formed integrally with the semi-cylindrical shell 10 and evenly arranged on the outer surface of the cylindrical shell 10 . On the cylindrical shell formed by the two semi-cylindrical shells 10 , the number of heat conducting fins 7 is an even number, and the assembled position of the heat conducting fins 7 is perpendicular to the tangent direction of the semi-cylindrical shell 10 . On both sides of each heat conduction fin 7, a thermoelectric power generation module 9 is installed and fixed by welding, and the contact surface is evenly coated with high temperature resistant heat conduction silicone grease to improve the thermal conductivity. Preferably, six thermoelectric power generation modules 9 are respectively installed on two sides of each heat conduction fin 7 . The thermoelectric power generation module 9 can adopt the HZ20 series thermoelectric power generation chips produced by Hi-Z Company, and the power generation of a single chip can reach about 19W. All the thermoelectric modules 9 on each heat conduction fin are electrically connected in series and output externally through a DC-DC conversion circuit. The cold ends of several thermoelectric power generation modules 9 on each side are uniformly attached to a cooling pipe 4, fixed by welding and coated with heat-conducting silicone grease. The engine cooling system leads out a branch circuit, and injects coolant into each cooling pipe 4 through a pressure regulating valve, so that the flow rate and pressure of the coolant in each cooling pipe 4 are kept consistent, ensuring that the cooling effect of all thermoelectric power generation modules 9 is uniform, and the cooling The liquid flow direction is parallel to but opposite to the engine exhaust flow direction. The coolant flows through each cooling pipe 4 and then gathers, and is adjusted to the pressure of the engine cooling system through a pressure regulating valve, and flows into the engine cooling pipe to form a cycle. Put the heat insulating gasket B13 on the exhaust pipe 1 at both ends of the assembled semi-cylindrical shell 10 at equal distances, and install the same two pieces of cooling channel support discs A2 and B8 on the heat insulating gasket B13, and support the discs A2 and B8 The connection method similar to the semi-cylindrical shell 10 can be adopted, that is, it is formed by splicing and welding two semi-circular discs, and the support disc A2 and the support disc B8 are processed with grooves that match the size of the cooling pipe 4, and each cooling The pipeline 4 is clamped and fixed by the fastening device 3 , as shown in FIG. 2 , and a certain pre-tightening force is applied to ensure that the thermoelectric power generation module 9 is closely attached to the cooling pipeline 4 and the heat conduction fins 7 . A certain number of screw holes are reserved on both end surfaces of the semi-cylindrical shell 10, through which a series of slender connecting bolts 11 connect the semi-cylindrical shell 10 with the support discs A2 and B8, but do not touch. A series of heat insulating washers A12 are arranged between the connecting bolts 11 and the supporting discs A2 and B8 to minimize the temperature rise of the supporting discs A2 and B8 caused by the heat conduction of the connecting bolts 11, while affecting the cooling liquid temperature in the cooling pipe 4 Impact. An insulating gasket B13 is arranged between the support disks A2 and B8 and the exhaust pipe 1 to prevent the heat of the exhaust pipe 1 from being conducted to the cooling pipe 4 through the support disks A2 or B8. Both the heat insulating gaskets A12 and B13 can be made of elastic heat insulating materials such as rubber, and can form a certain supporting force after being heated and expanded.

Claims (6)

1. the finned automobile exhaust thermoelectric generating device of the straight plate of cylindrical shell, between Three-component Catalytic Converters for Automobiles and silencerBlast pipe on; It is characterized in that: described device comprises semicolumn shell, heat transmission fin, thermoelectric generation module, cooling tubeRoad, support disk A, support disk B, heat-insulating washer A and heat-insulating washer B; Two identical semicolumn valve jackets existOn blast pipe, semicolumn shell outer surface arranges heat transmission fin, on the two sides of each heat transmission fin, thermoelectric generation module is installed, everyThe some thermoelectric generation module cold junctions of one side are unified to be fitted tightly with cooling pipe, phase on the blast pipe at the two ends of semicolumn shellThe equidistant heat-insulating washer B that puts, and identical two support disk A and B are installed on heat-insulating washer B, each coolingThe two ends of pipeline are clamped and are fixed on by fastener in two described support disk; Described support disk is by connectingBolt is connected on two end faces of semicolumn shell, between described connecting bolt and two support disk, arranges heat-insulating washer;Described heat-insulating washer A and heat-insulating washer B all adopt the manufacture of elasticity heat-insulating material; Two described semicolumn shells are by eachFrom mounting boss on fastening bolt be closely connected on blast pipe; Or by welding manner, semicolumn shell is welded on to rowOn tracheae; Described heat transmission fin is evenly arranged in the outer surface of cylindrical shell, is arranged on the fitting recess of semicolumn shell, fasteningBolt is fixed, or with the machine-shaping of semicolumn shell one.

2. the finned automobile exhaust thermoelectric generating device of the straight plate of a kind of cylindrical shell according to claim 1, is characterized in that: instituteThe length of the fitting recess of stating and semicolumn columella are to equal in length, and groove depth is no more than 20% of semicolumn shell axial width.

3. the finned automobile exhaust thermoelectric generating device of the straight plate of a kind of cylindrical shell according to claim 1, is characterized in that:In described fitting recess and heat transmission fin and fitting recess contact surface smear heat-conducting silicone grease; Importing fin and thermoelectric power generation mouldOn the contact-making surface of piece, be coated with heat-conducting silicone grease.

4. the finned automobile exhaust thermoelectric generating device of the straight plate of a kind of cylindrical shell according to claim 1, is characterized in that: instituteThe thermoelectric generation module of stating adopts HZ20 series thermoelectric power generation sheet, and monolithic generated output reaches 19W.

5. the finned automobile exhaust thermoelectric generating device of the straight plate of a kind of cylindrical shell according to claim 1, is characterized in that: instituteIn the cooling pipe of stating, cooling fluid is drawn branch road by engine-cooling system, and by pressure regulator valve, cooling fluid is injected to each cooling tubeIn road, flow velocity and the pressure of cooling fluid in each cooling pipe are consistent, coolant flow direction and engine exhaustFlow direction is parallel but contrary, and cooling fluid is flowed through after each cooling pipe and collected, and is adjusted to engine cool system by pressure regulator valveThe pressure of system, flows in engine cool pipeline and forms and circulate.

6. the finned automobile exhaust thermoelectric generating device of the straight plate of a kind of cylindrical shell according to claim 1, is characterized in that: instituteThe cooling pipe cross section of stating is rectangle.