Experimental investigation on working parameters of a Thermoelectric Generator-based system

In the text, the investigastion and optimization of a Thermoelectric generator-based system, under different conditions, has been studied. The investigation aim is to obtain the characteristic parameters of the system: the Seebeck coeff.(α), the Thomson coeff. (τ), the Heat transferred to the Thermoelectric generators (Qh) and the electrical conversion (η). The system is built using four resistive elements as heating system, fed by a controllable generator, and forced circulating air as heat sink. The heat flow, from the source to the sink, passes through a hot heat exchanger, the thermoelectric generators, and the cold heat exchanger. The two heat exchangers are designed in order to have the best heat exchange at each surface; this is obtained by creating a planar and compact are where the heat flow is primarly conduction-type, and providing a finned and wide surface where the heat flow is primarly convection-type. The circulation of air at the heat sink is obtained through the utilization of two fans. Utilizing the open-circuit data, the Seebeck coefficient, the Peltier coefficient, and the Thomson coefficient have been calculated, obtaining values of 187.7 μV/K,0.065 W/A,-0.043 V/K, respectively, at an average temperature of 345.731 K and temperature difference of 72.486 K. It’s been shown that the temperature range, explored with the system built, does cover the point in which the Seebeck effect has its max-value and, following, that such point does not match with the max efficiency point. Utilizing the controllable load-test data, macroscopic thermoelectric parameters as heat flows, electrical otuput power and electrical conversion efficiency, have been calculated. In the best condition occured, results as 144.538 W, 1.829 W,1.265 % have been measured for Qh, Pout, η, respectively, at an average temperature of 367.078 K and temperature difference of 103.418 K. All graphs show that the results are in strong agreement with the reported literature.