基于随机有限元的可靠度计算

基于随机有限元 ,研究了复杂机械零件的可靠度计算。根据随机有限元算法 ,编写了计算机程序 ,求出了变形、应力的均值和方差。应力、强度概率密度函数确定可采用应力 -强度干涉模型 ,用公式或数值积分求可靠度。应力、强度概率密度函数不确定 ,用 Monte- Carlo法。基于极限状态方程 ,研究了优化方法求可靠度 ,采用了遗传算法。考虑模糊因素对复杂机械零件可靠性影响 ,给出了模糊可靠度计算公式。随机有限元使复杂机械零件可靠性预测成为可能

Reliability Calculation Based on Stochastic Finite Element

Based on stochastic finite element, reliability calculation of complicated machine element is studied. According to algorithm of stochastic finite element, a computer program to solve means and variances of stress and deformation is compiled. If probability density functions of stress and strength are definite, stress strength interference model can be used to calculate reliability using formulation or numerical value integration. If probability density functions of stress and strength are not definite, Monte Carlo method is adopted. Based on limit state equation, optimization method can be used to calculate reliability and it is based on genetic algorithm. Fuzzy factor influence reliability is proposed. Stochastic finite element can predict reliability of complicated machine element.