大过载下固体火箭发动机内弹道计算

Internal ballistics calculation of solid rocket motor under high overload

大过载会对固体火箭发动机装药燃烧产生很大的影响。采用基于加速度的装药燃速增强模型,通过水平集(Level set)算法对非均匀燃速下的复杂燃面非平行层推移过程进行计算,得到了大过载下的内弹道性能.计算结果表明:过载对发动机内弹道影响不大,在过载作用方向上装药燃速增加,可能导致装药出现偏烧,绝热层提前暴露,造成该处烧蚀加剧.

High overload yields great influence on the grain combustion of SRM（solid rocket motor） in working process. Under nonuniform combustion of grain, a nonparallel combustion model of complicated grain was developed. The level set method was applied to calculate burning face location and internal ballistics property at different intervals. The computed results show that overload has little effect on SRM internal ballistics, since local burning rate of grain increases greatly in overload direction, leading to exposure of thermoprotection layer in high temperature gas and enhanced erosion in this position.