Optimization of the Heat Transfer Aspect of the Thermoelectric Power Generation System

Abstract

A combined type thermoelectric power generation system is proposed to improve the conversion efficiency of thermal energy. In that system, thermoelectric elements are directly attached to the outer wall of the channel of a working fluid without a heat transfer block in order to reduce the thermal resistance; but on the contrary, high performance heat transfer pipes can not be used. Therefore, the effective heat transfer rate of a working fluid is increased by using a larger diameter channel to increase the contact area of the fluid to the channel. The performance of the combined type power generator is experimentally and theoretically investigated and compared with that of the conventional separated type generator. The optimum condition for power generation is also discussed. It is clarified that the maximum efficiency of the combined type generator becomes higher and its optimum R_e number becomes larger compared with those of the conventional type. It is also made clear that the effect of the turbulence promoter on the maximum power output is negligible in the case of a generator having a large channel diameter.