电推进系统Xe物理特性计算方法

空间电推进系统的工质为Xe，其工作温度范围为-30～45 ℃，该范围覆盖Xe的临界点。在临界点附近，Xe可能呈现出多种形态，且对温度和压力变化十分敏感，采用传统状态方程在上述范围内计算其物理参数偏差最大可达30%。为解决这一问题，以CH₄作为参考流体，建立了一种基于对比态原理的Xe物理特性计算方法。该方法能够对包括气相、液相、超临界区域的所有状态Xe物理性质进行准确计算。试验研究与国外数据对比的结果表明，在整个压力-温度范围内，计算误差小于0.5%。

A theoretical method for xenon′s physical property used in electrical propulsion system

The possible operation temperature of propellant xenon in electrical propulsion system is between 30 ℃ and 45 ℃, which covers the xenon′s critical temperature. At the critical temperature, xenon′s state is sensitive to the operating pressure and the ambient temperature. The propellant may exhibit different forms. These characteristics make the traditional equation of state ineffective to calculate the p-V-T relationship in the above temperature range (max error may rise to 30 %). To solve this problem, a new calculation method based on the corresponding state principle was put forward for physical property estimation. The theoretical outcomes were compared with experiment data and available database. The results show that among the whole temperature and pressure range, the method is capable to predict the xenon′s physical property in gas, liquid, supercritical state with an error less than 0.5 %.