飞行过载下燃烧室凝相粒子沉积特征数值研究

Simulation research for accretion characteristic of condensed phase particle in SRM chamber with flight overload

固体发动机燃烧室部分凝相粒子在飞行过载作用下产生沉积,严重影响发动机工作性能。通过确定燃烧室粒子参数和建立燃烧室内两相流场数值方法,获得了发动机不同轴向过载下粒子运动及沉积规律。与试验数据进行对比分析,验证了计算方法的准确性。数值结果表明,随着轴向过载增大,后封头及喷管潜入段粒子沉积质量逐渐增大。沉积粒子粒径大于凝相粒子平均值,即粒子粒径越大,越容易沉积。轴向过载增大,减小了粒子在发动机内部的驻留时间,凝相粒子平均驻留时间均大于0.13 s。

The partially accretion of condensed particles in combustion chamber seriously affects the performance of the rocket motor under the overloaded action of flight. By determining the particle parameters and establishing the numerical method of two- phase flow field in combustion chamber, the particle movement and accretion law was obtained with the different axial overloads.The accuracy of the calculation method was verified by comparing with the experimental data.The numerical results show that with the in- crease of the axial overload, the accretion quality of the particle is gradually increased in the rear dome and the entrance region of submerged nozzle.The size of accretion particles is greater than the average value and the particle with larger particle size is much easier to be deposited.The residence time of the particles is reduced with the increases of the axial overload in the SRM.It is greater than 0.13 s for the average residence time of the condensed phase particle.