铝镁贫氧推进剂固冲发动机沉积数值模拟

Numerical simulation of deposition for aluminum/magnesium-loaded fuel-rich propellant ducted rockets

基于随机轨道模型和Mundo沉积模型,对固冲发动机三维两相流场进行了数值模拟,讨论了不同进气道进气角度、燃气发生器出口构型以及颗粒相入口边界处粒子粒径分布、燃烧生成的三氧化二铝的重附率等参数对发动机沉积的影响.结果表明,进气角度变化对沉积分布位置影响不大,随着进气角度的增加,进气道附近沉积分布逐渐不均匀;增加燃气发生器出口喷孔数量,不利于减少沉积;重附率变化对沉积分布影响不大;在忽略大粒子颗粒沉积情况下,随着粒径的增大,沉积量存在一个极大值.

Based on stochastic trajectory model and Mundo deposition model, the 3-D two-phase flow field in solid rocket ramjet was numerically simulated. The influences of the inlet angle, the burner exit configuration, particle size distribution at particle boundary and condensing fraction of Al2O3 on the deposition were discussed. The results indicate that the change of inlet angle has a little effect on the depositing position, and with the increase of inlet angle, the deposition around inlet will be distributed irregularly. We can also find that increasing the gas generator nozzle numbers is adverse to reduction of deposition. The change of condensing fraction has a little effect on the depositing position, and with the increase of particle diameter, the total deposition mass has a maximum value if deposition from big particle is neglected.