Research On Performance Of Automobile Waste Heat Recovery System Based On Thermoelectric Generator

In recent years,with the rapid development of the world economy,people have paid more and more attention to the energy crisis and environmental issues,and the development and utilization of renewable energy has been widely valued by various countries.As a new energy technology in recent years,thermoelectric power generation technology can not only improve the utilization efficiency of traditional energy,but also can be used for the acquisition of renewable energy.It has received extensive attention from researchers.After years of development and utilization,thermoelectric power generation technology has been widely used in various fields,and there is a wide range of applications in the field of vehicle engineering.This article mainly focuses on how to improve the thermoelectric efficiency of thermoelectric module.The application of thermoelectric power generation technology in the circuit of automobile engine cooling system was researched and discussed.The main research work of this paper is as follows:(1)The thermoelectric performance of thermoelectric module based on porous heat collector,as opposed to the traditional heat collector,were comprehensively studied.The influence of hot side temperature uniformity on thermoelectric performance was discussed.Under various hot side temperatures,the thermal load distribution,load current,load voltage,and load power of two types of collector plates were tested using the method of control variables.In addition to the experimental tests,the temperature distribution of the collector plates as well as the performance of thermoelectric module were numerically simulated and tested.The results showed that the thermoelectric performance estimated by the numerical simulation was consistent with that obtained from the experimental tests.The thermoelectric performance of thermoelectric module with a uniform hot side load distribution was noticeable better than of that with a non-uniform hot side load distribution.The thermoelectric module based on a porous heat collector achieved a better thermoelectric performance output.(2)The thermoelectric performance of thermoelectric module based on various heat transfer medium and pressure loads were comprehensively studied.The influence of contact thermal resistance on thermoelectric performance was discussed.Perform experimental tests on the load current,load voltage and load power of the thermoelectric module under different temperature difference,heat transfer medium and pressure loads.The results showed that different heat transfer medium and different pressure loads have a great impact on the thermoelectric performance of thermoelectric module.Compared with the thermoelectric module without heat transfer medium,a suitable heat transfer medium can effectively reduce the contact thermal resistance and improve the thermoelectric performance.Among them,the thermal conductive grease is better than graphite paper,and the thermal conductive grease with high thermal conductivity is the best.At the same time,in all working conditions of the medium,the thermoelectric performance of thermoelectric module increases with the increase of pressure load,and its growth rate gradually decreases.(3)A waste heat recovery thermoelectric device applied to the loop of the automobile cooling system was designed.It has conducted heat transfer simulation and thermoelectric power generation simulation.Among them,a variety of internal structure designs are carried out on the heat collector.In order to maximize the thermoelectric performance of thermoelectric module without affecting the original work of the automobile engine cooling system.The simulation results show that the appropriate size and internal diversion structure of the heat collector can minimize the reduction in the flow rate of the inlet and outlet coolant flow rate.At the same time,the hot side surface of thermoelectric module has good temperature uniformity.It can not only ensure the normal operation of the automobile cooling system,but also maximize the thermoelectric performance of thermoelectric module.