A novel numerical case-study for thermoelectric module with hollow semiconductor

Abstract

Most recently, some researchers proved that the hollow structure for p-type and n-type semiconductor of thermoelectric can improve its performance. However, the impact of the inner to outer radius (as the most important geometric parameter of hollow leg) for all thermal, mechanical, exergetic and economic characteristics have not been properly clarified. Hence, in this case-study, attempts are made to evaluate a thermoelectric generator with hollow semiconductor under different values of ITO (the ratio of inner radius to the outer radius of semiconductor) from all aforementioned viewpoints. Based on the results, although larger ITO generates significantly higher power, its mechanical reliability is diminished. Indeed, a critical value of ITO was recognized after which the mechanical stress passes yield stress and makes failure in the legs. Increment of ITO 2 from 0.1 to 0.8 increases the output power from around 0.01 to around 0.025 which means 2.5 times higher. Besides, a remarkable 100% reduction in $/Watt and 20% improvement in exergetic efficiency are observed due to the reduction in the used material in hollow semiconductor. However, the ITO should be selected considering the mentioned critical value to avoid the passing from yield stress. The impact level of ITO on each parameter is different with each other as reported in this research.