Effect of core flow heat transfer enhancement on power generation characteristics of thermoelectric generators with different performances

Abstract

In this study, the effect of enhancing the core flow heat transfer with metal foam on the performance of thermoelectric generators with different power generation characteristics is studied experimentally. Filling the core flow area of the gas channel in a thermoelectric generator with metal foam can greatly improve the heat transfer capacity of the gas channel with a small pressure loss, thereby improving the power generation efficiency. The results show that, first, the heat transfer enhancement achieved by partially filling the core area of the gas channel with metal foam can significantly improve the performance of thermoelectric generators, the maximum output power is about 1.5 times higher than that of the unfilled channel. Second, for a thermoelectric generator with different modules, the friction coefficient for different filling ratios increases by about 16 times at most, while the Nu value increases by only three times at most, and according to the PEC of the gas channel, metal foam with high filling rate and low pore density is more suitable for the thermoelectric generator. Third, it is more appropriate to use the thermoelectric module with a high figure of merit as the selection criterion for deciding whether to adopt the technique of enhancing heat exchange through the gas channel. The maximum output power and efficiency of the thermoelectric generator using the high figure of merit module are 300% and 160% higher than those of the thermoelectric generator using the low figure of merit module, respectively.