氮稀释气体氧碘化学激光3维喷管流动模拟

 应用改进的3维化学反应流程序，对基于RADICL装置、以氮气为稀释气体的化学氧碘激光喷管流动做了数值模拟。给出了达到合适副气流穿深的主副气流匹配条件，考虑了提高水汽流量、改变主副气流总温对增益系数的影响，比较了与以氦气为稀释气体的不同特点。结果发现：氮气作为稀释气体条件下，混合气体的流速低，静压大，在亚声速区驻留时间长，碘分子离解快，使得增益系数峰值增大，且下降快。模拟结果提示：改变喷管结构，将副气流喷孔下移，增益分布得到了改善。

Simulation of 3D chemical oxygen-iodine laser nozzle-flows with nitrogen diluent

Numerical simulation of chemical oxygen-iodine laser(COIL) flows with nitrogen diluent based on RADICL setup was carried out.A finite-volume code was used to solve 3D compressible N-S equations with 10 components,13 non-equilibrium chemical reactions.The condition for the secondary flow to match the primary flow was obtained,and the proper penetration-depth of the secondary flow was found.As a result,the rate between the secondary and the primary dynamic pressures was about 13.0.Simulation showed that gases flow slower and stay longer in the region of the nozzle and the iodine molecules dissociate faster with nitrogen diluent than that with helium diluent.It was found that the gain has a big peak near the throat of the nozzle,and decreases rapidly downstream.It showed that moving the secondary inlets downstream,a proper gain distribution would be obtained.