【摘要】 通过实验测定了不同氮气预冷温度、热负荷条件下冷冻消融探针内J-T节流制冷器温度与流量。实验结果表明:冷冻消融探针工作温度随氮气预冷温度变化而变化,热负荷越大所需氮气预冷温度越低;氮气预冷温度过低会造成制冷量浪费与回热换热器换热效率降低;氮气流量随高压氮气出口温度的降低而增大,除临界区域外氮气计算流量符合测试结果。更多还原

【Abstract】 Various experiments were conducted to measure the temperature and flow rate of a Joule-Thomson cryostat corresponding to different precooling temperatures of nitrogen and thermalload.The results demonstrated that the steady-state temperature of cryoprobe changed with precooling temperature,and that the greater the thermal load,the lower the requisite precooling temperature of the nitrogen passing through the Joule-Thomson cryostat.The experiments further indicated that too low precooling temperature of nitrogen is not necessary as it may cause a great waste of nitrogen and lower heat exchanger efficiency;and the nitrogen flow rate increased as the outlet temperature of supply nitrogen decreased.The calculated results of nitrogen flow rate correlated well with the experimental measurement.更多还原