随机参数超空泡射弹的动力稳定性和可靠性

针对轴向随机载荷作用下超空泡射弹结构的动力不稳定问题，建立超空泡射弹结构动力偏微分方程,利用Bolotin方法对其动力稳定性进行数值计算。考虑射弹结构参数随机性的影响，采用随机因子法求出随机参数射弹结构的动力不稳定区域边界，利用求解随机变量数字特征的代数综合法，推导出动力不稳定区域边界的均值和方差。在此基础上，对结构的非概率可靠性进行了分析，并讨论了参数的随机性对射弹结构动力不稳定性和非概率可靠性的影响。数值模拟结果表明，参数的随机性对射弹动力不稳定区域边界和非概率可靠性有一定的影响，其中，几何参数的随机性对射弹结构动力稳定性及可靠性影响较大。

Dynamic stability and reliability of a supercavitating projectile with stochastic parameters

Aimed at the dynamic instability problems of a supercavitating projectile subjected to an axial random load, a dynamic partial differential equation for the supercavitating projectile structure was established, and the dynamic stability was numerically calculated by Bolotin’s method. Considering the influences of the randomness of the structural parameters, the dynamic instability regions of the projectile were constructed by applying the random factor method, and the mean value and the variance of the boundary of dynamic instability regions were derived by using the algebra synthesis method. Based on the above, the non-probabilistic reliability of the projectile structure was analyzed. And the influences of stochastic parameters were discussed on the dynamic instability and non-probabilistic reliability of the supercavitating projectile. The computational results indicate that the parameter randomness can affect the dynamic reliability region boundary and non-probabilistic reliability. And the randomness of the geometric parameters has more influences on dynamic instability and reliability.