Development of Thermoelectric Conversion System for Waste Heat Recovery of Automobile Engine Exhaust Gas

Abstract

In the viewpoint of energy reutilization, this study combined high efficiency heat transfer with thermoelectric conversion technology to construct an efficiency testing platform for the waste heat recovering thermoelectric conversion system for real vehicles. A Toyota 2200c.c. vehicle with four-cylinder four-cycle engine was used for vehicle test to discuss the influence of the vehicle's engine speed and external cooling air flow on the energy output of the waste heat recovering thermoelectric conversion system. This study found that the energy output increases with the engine speed. However, if the engine speed is too high (exceeding 2500rpm), the thermoelectric generator can be overheated and damaged, which should be avoided. In addition, there is an optimal external cooling air flow generating the maximum energy output. The optimal external cooling air flow is 0.04 m3/sec in this study. At present, the 6 thermoelectric generator modules connected in series have the maximum electric power (P) output about 16W when the blowing air flow is 0.04 m3/sec and the engine speed is 2500 rpm.