基于合理验算点失效相关机械系统可靠性分析及仿真

BASED ON REASONABLE DESIGN POINT RELIABILITY ANALYSIS OF FAILURE-DEPENDENCE MECHANICAL SYSTEMS AND SIMULATION

以共因失效为研究背景,根据改进的一次二阶矩原理,探讨多重联合失效概率近似计算时合理验算点的选择及其确定方法,从共因失效的内在机理出发,揭示共因载荷的分散性是引起机械系统零件间失效相关性的本质原因,并建立失效相关系数及其主要影响因素之间的近似关系。针对典型机械系统,给出系统可靠度计算的一般表达式,利用条件可靠指标法,通过不断降维实现系统可靠度求解,并给出其计算方法。在此基础上编制Matlab程序,实现机械系统可靠性分析的计算机仿真。最后,通过算例进一步验证该方法的可行性、有效性。

Taking common cause failure as the research background, according to first-order second-moment theory, the choice and calculating method of reasonable design point are discussed, when computing multi-class union failure probability. From inherence mechanism of common cause failure, it was brought to light that the essence cause for failure dependence among mechanical parts is deviation of common load, the relationship between failure correlation coefficients and main influencing factors is established. For serial, parallel and voting systems, general expression of reliability calculations is given using failure- condition reliability index, reliability of mechanical systems can be calculated with dimension reduction, and iterative process is given. Finally, Matlab common program was worked out and the simulation for reliability calculations of mechanical systems was realized. An example is given to further demonstrate the feasibility and effectiveness of the method.