为了研究百赫兹以上的高频回热器的特性及其对脉管制冷机性能的影响,采用回热器数值计算程序RE-GEN3.2对高频回热器的尺寸参数和运行参数进行优化设计,并研制出一台运行频率为120 Hz的斯特林型脉管制冷机,其无负荷制冷温度为47.8 K,在78.6 K有8.0 W制冷量.初步证明配合使用更高的充气压力、采用小水力直径的回热填料以及缩短回热器长度,能够使得回热器在百赫兹以上的高频下仍然保持较高的效率.另外,实验显示该百赫兹高频脉管制冷机能够实现快速降温,脉管方向性问题也得到较好的抑制.
In order to study the characteristics of the high frequency regenerator and its influence to the performance of the pulse tube cryocooler,this paper optimized the geometry and operating parameters for the high frequency regenerator by using the numerical model,known as REGEN 3.2.A Stirling type pulse tube cryocooler operating at 120 Hz was designed,fabricated and tested.This cryocooler achieves a no-load temperature of 47.8 K,and can provide a cooling power of 8.0 W at 78.6 K.The result proves preliminarily that with higher frequency together with higher charging pressure,smaller hydraulic diameter and shorter regenerator,it is still possible to let the regenerator keep high efficiency.The experiment also indicated that this cryocooler can cool down fast and the pulse tube orientation effect was well suppressed benefiting from this higher frequency characteristic.