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 ITO² 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.

最近，一些研究人员证明，热电的p型和n型半导体的中空结构可以提高其性能。然而，内到外半径（作为空心腿最重要的几何参数）对所有热、机械、火用和经济特性的影响尚未得到适当阐明。因此，在本案例研究中，尝试从上述所有观点评估不同 ITO 值（半导体内半径与外半径之比）下具有空心半导体的热电发电机。根据结果​​，虽然较大的 ITO 会产生显着更高的功率，但其机械可靠性会降低。事实上，ITO 的临界值已被识别，之后机械应力通过屈服应力并在腿中产生故障。²从 0.1 到 0.8 将输出功率从大约 0.01 增加到大约 0.025，这意味着高出 2.5 倍。此外，由于减少了中空半导体中使用的材料，观察到 $/Watt 显着降低了 100%，火用效率提高了 20%。但是，在选择 ITO 时应考虑到提到的临界值，以避免传递屈服应力。正如本研究报告的那样，ITO 对每个参数的影响程度彼此不同。