地面与飞行状态下固体发动机比冲差异性分析

The ground-to-flight performance differences for solid rocket motors are analyzed.The main reason for the difference of motor performances between ground and flight lies in the energy conversion efficiency from motor to missile in flight state,which is related to the mass ratio of missile,and the ratio of the absolute missile flight velocity to the effective motor exhaust velocity with respect to the missile.Besides,the division among the synthetic sensed acceleration direction,the thrust direction of SRM,and the change of missile mass may affect the identification of specific impulse.According to the existing public reports and the analysis of several missiles,the difference of specific impulse for SRM is about 1 s and basically less than 1.5 s.The analysis results show that the specific impulse of the motor can be identified on an engineering basis with the sensed acceleration model and the internal ballistic of motor.However,the correction of conversion efficiency should be considered in performance identification using sensed acceleration analysis method.