5W@80K自由活塞斯特林制冷机工况及重力特性实验研究

Characteristic of working conditions and gravity investigation of 5 W@80 K Stirling cryocooler

利用现有的脉冲管制冷机性能测试实验台,针对某型号自由活塞斯特林制冷机,设计了热端水冷器并进行了性能测试。实验研究了工作频率、充气压力、输入功率等参数对制冷机性能的影响规律,结果表明斯特林制冷机的最佳运行工况为充气压力2.0 MPa,频率42 Hz。改变冷头在竖直方向和水平面不同的朝向,实验结果表明冷头竖直向下时最低制冷温度低于冷头水平布置和冷头向上的情况,但差距最大1.2 K,证明板弹簧的轴向刚度与排出器质量的比值较大,排出器重力产生的静位移较小;冷头水平放置处于不同圆周方位的制冷性能变化很小,证明排出器的密封间隙保持较好。

In order to find out the Stirling cryocooler′s performace,water cooler of the hot end was designed and performance testing was conducted on an existing pulse tube refrigerator performance tester.The influences of operating frequency,filling pressure,input power on Stirling cryocooler were investigated during experiments,so as to determine the optimized operating conditions.The results show that the optimized operating condition was 2.0 MPa of filling pressure and 42 Hz of working frequency.The gravity characteristic was done by changing the cold head arrangement direction and result showed that the cooling performance under the condition of vertical downward cold head was better than horrizon and upward,however,the difference was only 1.2 K,which indicated that the ratio of spring plate axial stiffness to mass was large enough to ignore the effect of gravitation on the displacer static displacement.The cooling performance had little change when cold head was at different circumference position in horizontal direction,which indicated that the displacer had a excellent clearance seal.