Abstract: A numerical model of a cylinder of marine steam turbine was established for analyzing its reliability under the impact of fractured blades. In this model, the initial speed, mass, yield strength, modulus of elasticity of the fractured blades, as well as the elastic modulus, yield strength and ultimate strength of the cylinder material were taken as random variables. A certain number of samples were acquired using Monte Carlo method. The distribution of random variables was obtained via curve-fitting using a few samples among them. Then, 50 groups of initial values of random variables were obtained using the program for generating random variables, and the process of penetration of the cylinder was simulated with this model. The maximum equivalent stress of the cylinder was obtained. Adopting the ultimate strength criteria and W-testing, the maximum equivalent stress of the cylinder was validated to obey the normal distribution, and the destructive probability of the cylinder was obtained. A reliability analyi

Key words: shock , steam turbine , blade , cylinder , impact , reliability , Monte Carlo simulation

摘要： 建立了分析舰用汽轮机汽缸在断裂动叶片撞击下的可靠性的数值计算模型。取断裂叶片初始撞击速度、质量、屈服强度、弹性模量以及汽缸材料的弹性模量、屈服强度和极限强度作为随机变量，利用蒙特卡罗方法得到一定数量的样本采用对较小的样本数量进行拟合的方法，用产生随机数程序得到50组随机变量的初始值，建立断裂叶片撞击汽缸的数值计算模型进行仿真计算，得到叶片撞击下汽缸的最大等效应力值。利用强度极限准则，采用W检验得到了汽缸最大应力分布模型及功能函数，得到汽缸的破坏概率，研究汽缸在断裂叶片撞击下的可靠性分析方法。

关键词: 冲击, 汽轮机, 叶片, 汽缸, 撞击, 可靠性, 蒙特卡罗模拟