加筋板架击穿概率分析

为评估攻击武器作用下舰船结构的安全性,对战斗部冲击载荷作用下加筋板架的击穿概率进行分析.取初始撞击速度、战斗部密度、材料的弹性模量和极限强度作为随机变量,利用随机数生成程序得到50组随机变量的初始值;采用有限元程序进行仿真计算,得到战斗部击穿板架后的末速度值,并检验末速度是否服从正态分布,若不服从则利用最大熵法拟合末速度的概率密度函数;考虑战斗部撞击点和板架加强筋的相对位置关系,采用速度破坏准则,利用蒙特卡罗方法模拟得到不同入射角度的战斗部击穿单层和双层加筋板架的概率.该方法所用样本数量少,充分利用了样本信息,效率较高,具有一定实际应用价值.

Penetration probability analysis of stiffened plate-grid

To evaluate the security of warship subjected to the attacking weapon,the penetration probability is analyzed for the stiffened plate-grid striked by projectiles.The initial striking velocity and density of projectiles,the elastic module and limited strength of stiffened plate are considered as random variables.The original values of fifty groups of random variables are gotten through the random data generation program,and the end velocities of projectiles penetrating plate are derived by finite element program.Then the end velocities are validated whether they obey the normal distribution,if they do not,the probability density distribution function of the end velocities can be gotten through the method of maximum entropy.The relative ubiety between impactive location and stiffener is taken into account,and the rule of velocity destruction is adopted,so the penetration probability of single-layer and double-layer stiffened plates penetrated by projectiles at different incident angles is gained through the Monte Carlo method.The presented method,which uses a small number of samples and makes full use of information of each sample,can be adopted by practical application.