气动激光器非平衡喷管流的数值模拟

Numerical Simulation for Non Equilibrium Nozzle Flow in a Gasdynamic Iaser

利用两步ＭａｃＣｏｒｍａｃｋ显示格式对气动激光器喷管内的平衡、非平衡流动进行了研究．算例表明，该差分格式具有高效、简易、易收敛的特点，适用于拟一维喷管内平衡、非平衡流计算．在二振型二温度弛豫模型及典型ＣＯ２－Ｎ２－Ｈ２Ｏ组分条件下，对弛豫时间的实验数据进行了综合整理及分析，在此基础上。

By using the time correlation analysis, the premixed non equilibrium nozzle flow in a gasdynamic laser is numerically simulated. In particular, the non equilibrium flow of N 2 through the nozzle is calculated, which is preliminary work for the study of aftermixed gasdynamic laser. With the relaxation model for two vibration modes and two temperatures, and under the condition of typical constituents of CO 2 N 2 H 2O, the experimental data on the relaxation times are analyzed. It has been found that the relaxation times given in the literature elsewhere are different from what has been obtained by the authors. The effects of the relaxation time on the calculation results are studied and a relaxation time mode is put forward. The two step MacCormack explicit different scheme is used to simulate the quasi one dimensional vibrational non equilibrium nozzle flow. Several examples show that this scheme is of high efficiency and with easy convergence. The calculation results are compared with experimental ones and those by other methods.