Numerical and Experimental Studies on Non Equilibrium Flows in MPD Arc Jets.

考虑非平衡电离解离和热非平衡，对稳态一维自场MPD电弧射流进行了数值研究。得到了以下结果：1。在氩的情况下，电流浓度在通道的入口和出口都可以观察到，而在氢的情况下，电流浓度只在通道的出口可以观察到。在氩的情况下，电导率与电子温度的3/2次方成正比，而在氢的情况下，电导率与电子温度的根号成正比。电弧射流的运行主要受特征速度和入口马赫数的影响，也受特征能量的影响。以氮气和氩气为推进剂，研究了缩管尺寸和阳极几何形状（喷嘴型、火炬型、直管型）对电弧射流性能的影响。得到了以下结果：1。对于氮气推进剂，可以假设电弧射流中分子的电子温度、振动温度和旋转温度处于平衡状态。随着收缩器长度和直径的减小，电弧射流的性能得到改善，但在一定的临界直径下，电弧射流不能形成。电弧射流喷出气体的温度和热含量受收缩器几何形状的影响，但气体压力对其影响较小。以氩气推进剂为例，在电弧电流50 ~ 350 A范围内，火炬型和直径小、质量流量小的推进剂性能最好。

Numerical Studies on steady one-dimensional self-field MPD arc jets were conducted, taking into consideration the non-equilibrium ionization and dissociatin, and the thermal non-equilibrium. Following results were obtained :1. The current concentration is observed at the entrance and the exit of the channel in the case of argon and it is observed only at the exit of the channel in the case of hydrogen.2. The electrical conductivity is proportional to the 3/2 powers of electron temperature in the case of argon, while it is proportional to the root of that in the case of hydrogen.3. The operation of arc jets is influenced mainly by a characteristic velocity and entrance mach numbers, and also by a characteristic energy.Experimental studies on the effect of constrictor size and anode geometry (nozzle type, flare type, straight type) on the performance of arc jets were conducted using nitrogen or argon propellants. Following results were obtained :1. The electron temperature, the vibrational and rotational temperatures of molecules can be assumed in equilibrium in arc jets for the case of nitrogen propellant.2. The performance of arc jets is improved as the length and diameter of the constrictor are decreased, but the arc does not established under a critical diameter.3. The temperature and heat content of the gas ejected from arc jets are influenced by constrictor geometry but the effect of gas pressure on them is small.4. In the case of argon propellant, in the range of arc current, 50-350 A,the best performance was obtained for the flare type andhe with small diameter, operated at a low mass flow rate.