端部热导分配对半导体器件制冷性能的影响

Influence on performance of thermoelectric cooling devices of thermal conductance distribution between hot and cold ends

端部散热设计和优化是改善半导体制冷器件性能和推广其应用的关键环节。针对半导体器件,研究冷端、热端热导分配对制冷性能的影响,通过引入冷端热导在冷、热端总热导中的分配比参数,利用一维解析方法求解获得了半导体器件制冷性能参数与分配比的关系。在此基础上,分析了在不同工作电流、热电臂结构、外流体温度及总热导等情况下,最大制冷量和最高制冷系数对应的最佳分配比。结果表明:存在最佳分配比在0.35~0.45之间使得半导体制冷器件的制冷性能达到最优,且随着工作电流的增加,最佳分配比减小;冷热端流体温差越大,最佳分配比越小;热电臂几何参数和制冷片冷热端总热导对最佳分配比影响可忽略。

Heat dissipation design and optimization of cold and hot end is a key link to improve the performance of thermoelectric cooling devices and promote their application.This paper focuses on the thermoelectric cooling device,and studies the influence of the thermal conductance distribution between the cold and hot end on the cooling performance.In order to comprehensively consider the influence of various physical factors of heat,electricity and its conversion process,the distribution ratio parameter of the thermal conductance of the cold end in the total thermal conductance(w)is introduced,and the relationship between the cooling performance parameters of the thermoelectric cooling device and the distribution ratio are solved using the one-dimensional analytical method.On this basis,the optimal distribution ratio corresponding to the maximum cooling capacity and the highest cooling coefficient of performance(COP)under different operating currents,thermoelectric arm structure,external fluid temperature and total thermal conductance is analyzed.The result show that there is an optimal w between 0.35 and 0.45 that the cooling performance of the thermoelectric cooling device reaches the optimal.The cooling capacity and COP always have the same trend and will firstly increase,and reach up to the maximum,and then decrease with the increase of w,and there is an optimal w so that the cooling performance of the thermoelectric cooling device is optimized.The change of operating current has the greatest influence on the optimal w,and as the operating current increases,the optimal w decreases.The greater the temperature difference between the hot and cold fluids,the smaller the optimal w.The geometrical parameters of the thermoelectric arm and the total thermal conductance of the cold and hot ends of the thermoelectric cooling device have negligible influence on the optimal w.