Wei Shuhuan, Feng Huijun, Chen Lingen, Ge Yanlin
Institute of Thermal Science and Power Engineering, Wuhan Institute of Technology, Wuhan 430205, China.
School of Mechanical & Electrical Engineering, Wuhan Institute of Technology, Wuhan 430205, China.
Entropy (Basel). 2020 Oct 25;22(11):1206. doi: 10.3390/e22111206.
With the aid of constructal theory and entransy theory, a Tau-shaped fin (TAUSF) is investigated in this paper, and the widths of the bend end and elemental fins are assumed to be different. The construct of the TAUSF is optimized by the minimum equivalent thermal resistance (ETR) obtained by entransy dissipation rate. The constraints of total enveloping volume and fin material volume are considered. The results show that in the specified range of width ratio, the twice minimum ETR of the TAUSF can be yielded by an optimal width ratio and an optimal length ratio. In addition, comparing the optimal performance of the TAUSF with the counterpart of a T-shaped fin, the former sacrifices a small amount of heat transfer performance and its stiffness increases due to its structure with the bend end. The optimal structure of the TAUSF yielded from ETR minimization is conspicuously different with the counterpart yielded from maximum thermal resistance minimization. Comparing the thermal performances of the two optimal constructs, the ETR of the former optimal construct is declined by 10.58%, whereas the maximum thermal resistance is augmented by 5.22%. The former optimal construct can lead to the uniformity of temperature gradient and the reduction in thermal stress, and can guide the engineering designs of practical fins.
借助建构理论和传递熵理论，本文对一种Tau形翅片（TAUSF）进行了研究，并假设弯曲端和单元翅片的宽度不同。通过传递熵耗散率得到的最小等效热阻（ETR）对TAUSF的结构进行了优化。考虑了总包围体积和翅片材料体积的约束。结果表明，在特定的宽比范围内，TAUSF通过最优宽比和最优长比可产生两次最小ETR。此外，将TAUSF的最优性能与T形翅片的对应性能进行比较，前者牺牲了少量的传热性能，并且由于其带有弯曲端的结构，其刚度增加。由ETR最小化得到的TAUSF的最优结构与由最大热阻最小化得到的对应结构明显不同。比较两种最优结构的热性能，前者最优结构的ETR下降了10.58%，而最大热阻增加了5.22%。前者最优结构可导致温度梯度的均匀性和热应力的降低，并可为实际翅片的工程设计提供指导。
