空间脉冲管制冷机的热力学第二定律分析

利用数值模拟的方法对空间用微型脉冲管制冷机进行了热力学第二定律分析。计算结果表明：脉冲管制冷机中蓄冷器是产生不可逆损失最大的部件。小孔型到双向进气型脉冲管制冷机性能改善的原因在于：通过蓄冷器中的气体量减少，压缩机连管、蓄冷器和冷端换热器中的不可逆损失减小，直接降低了压缩机的功耗；同时，蓄冷器中气体和固体之间的换热改善，减少了因蓄冷器中不完全换热而带来的制冷量损失，因而使得制冷量增加。计算结果表明，微型脉冲管制冷机从小孔型变化至双向进气型时，卡诺效率从14%提高到了16．9％。

The Second Law of Thermodynamic Analysis of the Pulse Tube Cryocooler for Space Application

Based on the numerical simulation, the second law of thermodynamics is applied to analyze the irreversible losses in a miniature pulse tube cryocooler (PTC) for space application. Simulation results show that the regenerator is the main part generating irreversible losses in the PTC. The performance of double inlet PTC is better than that of orifice PTC. From the view of the second law of thermodynamics, the reasons of this improvement are as follows. Firstly, the helium gas through the regenerator is reduced, and then the irreversible losses in the regenerator, the connecting tube (between the compressor and regenerator) and the cold heat exchanger are reduced. Thus the power consumed by the compressor is less. In the mean time, the heat transfer between the gas and matrix is performed better, and the net refrigeration power is increased consequently. Simulation results show that Carnot efficiency of the PTC increase from 14% to 16 9% when the cooler change from orifice type to double inlet type.