液氦温区G-M型制冷机P-V图实验测试系统的建立及结果  

Measurement Apparatus of the P-V Diagram of a 4.2 K G-M Refrigerator

作　　者：张智勇[1] 刘景忠[1] 徐向东[1] 王莉[1] 张亮[1] 

机构地区：[1]中科院低温技术实验中心

出　　处：《低温与超导》1998年第1期19-25,共7页Cryogenics and Superconductivity

基　　金：国家自然科学基金

摘　　要：建立了一套液氦温区Ｇ－Ｍ型制冷机Ｐ－Ｖ图测试系统，测试装置主要包括制冷机进、排气和冷、热腔压力的压力测量系统及制冷机活塞位移的测量系统。该系统将制冷机动态压力、动态位移的测量信号通过采集系统送入微机中进行处理，可实时绘制压力及Ｐ－Ｖ图图形曲线，随时掌握不同结构不同工况下Ｇ－Ｍ制冷机压力损失和Ｐ－Ｖ图效率情况，为制冷机性能的改进、制冷机的理论分析及设计计算提供了可靠的实验依据。通过测试系统，测试了制冷机冷腔在不同制冷温度下的Ｐ－Ｖ图效率，指出在深低温区冷腔Ｐ－Ｖ图面积并不代表制冷机实际制冷量。A measurement system of the P-V diagram of a 4.2 K G-M refrigerator is established in this paper. The pressure curves vs. time of the 2nd stage cold space, admission line and exhaust line of the 4.2 K G-M refrigerator and the P-V diagram of the 2nd stage cold space can be obtained by the measurement system. By comparing the P-V diagram efficiency with the ideal and real cooling capacities, it was indicated that the increased P-V diagram area at low temperature (<8 K or so) doesn't represent the net increased cooling capacity. In addition, the pressure drops in the admission line and exhaust line greatly increase with the cooling temperature decreasing.

关 键 词：G-M型 制冷机 P-V图 测试系统 液氦 

分 类 号：TB651[一般工业技术—制冷工程]