【摘要】 通过直接状态方程法和热动力学公式法对HeⅡ的Joule-Thomson系数进行了分析和计算,并在计算结果的基础上,拟合得到了便于工程应用的经验方程.应用经典的紊流流动关联式和Fanning摩擦因子关系式对HeⅡ输送系统的压力损失进行了预测.利用系统的压力损失和Joule-Thomson系数分析并计算了由于负Joule-Thomson效应引发的系统温升.计算结果表明:应用状态方程法计算的结果与目前公开发表的应用热动力学公式的计算结果很接近;HeⅡ的流速和初始温度都会对最终的温升产生重要的影响.更多还原

【Abstract】 Calculating the Joule-Thomson coefficients of He Ⅱ is the precondition to determine the negative Joule-Thomson effect.The calculation and analysis of the Joule-Thomson coefficients of liquid He Ⅱ through the equation of state and thermodynamic identity were carried out and an empirical equation was obtained by curve fitting based on the results.The results obtained by applying the equation of state of He Ⅱ are similar to the data appeared in literatures.The Von-Karman-Nikuradse correlation and Fanning friction factor correlation were used to predict the pressure drop of the transfer system.The temperature rise caused by negative Joule-Thomson effect was obtained by the Joule-Thomson coefficients and pressure drop.The results show that the velocity and initial temperature of the He Ⅱ both are very crucial to the temperature rise of the transfer system.更多还原