In order to meet the cooling demand of a medium-wave infrared detector, a coaxial pulse tube cryocooler (PTC) working at temperature around 90 K has been designed. The cooling capacity is requested to exceed 7 W at 90 K with an input electric power of 100 W. The compressor is made based on an engineering prototype which has been successfully applied in space. Experimental studies have been carried out to improve the performance of the cold finger from the aspects of inertance tube, cold-side heat exchange, hot-side flow straightener. By carrying out these optimizations the PTC can achieve a 7.64 W cooling capacity at 90 K when the input electric power is 100 W, and its relative Carnot efficiency is higher than 15% at temperature between 80 and 100 K.

为了满足中波红外探测器的冷却需求，已经设计了工作在90 K附近的同轴脉冲管低温冷却器（PTC）。在输入功率为100 W的情况下，要求在90 K时的制冷能力超过7W。压缩机是根据已成功应用于太空的工程原型制造的。从惯性管，冷侧热交换，热侧整流器等方面进行了改进冷指性能的实验研究。通过执行这些优化，当输入电功率为100 W时，PTC在90 K时可以获得7.64 W的冷却能力，并且在80至100 K的温度下其相对卡诺效率高于15％。