大过载对固体火箭发动机粒子阻尼的影响

Based on discrete element method (DEM), the numerical simulation of particle damping in Solid Rocket Motor (SRM) under large overload (30 g) is carried out. The nonuniform particle spatial distribution is adopted to predict the particle damping under large overload to reveal the characteristics of particle space distribution and damping with different particle size. The results show that the spatial distribution and damping characteristics of particles in combustion chamber are significantly affected by overload (30 g), and the particle size determines the degree of this influence. Under the transverse overload, the large particles (diameter>30μm) in the combustion chamber will accumulate into a small region and thus create another particle-free region within a short time. With this distinct nonuniform space distribution the predicted particle damping shows an obvious decrease compared to the conventional prediction with uniform assumption. Up to 30% of damping effect will be reduced when the large overload is exerted within 5 ms, and this reduce is growing with increasing particle size, which needs the caution since it can cause server consequence in combustion instability of motor.