Reliability Analysis Method of Mechanical System with Correlated Failures.docxVIP

Reliability Analysis Method of Mechanical System with Correlated Failures , North China System Engineering Institute, CNGC Beijing, China E-mail  HYPERLINK mailto:bjthm@126.com bjthm@126.com 机械系统可靠性分析方法与相关故障 Hongmao Tu ?中国兵器中国北方系统工程研究所， 中国北京 电子邮件bjthm@126.com Abstract—This paper presents a general mechanical system reliability modeling and analysis method, which consider the correlations of failure modes. Firstly, the performance functions which mathematically represent the failure modes are linearized based on FORM (First Order Reliability Methods), and the correlation coefficient matrix of those functions is calculated. Then, the PFTA (Probabilistic Fault Tree Analysis) method is adopted to establish the system reliability model which can take the correlations into account. Finally, effective algorithms such as G-FOMN (General First Order Multinormal Method) are used to quantify the system reliability, and the sensitivities of the system reliability index with respect to each failure mode, as well as the mean value and standard deviation of each random variable are also calculated. An engineering example demonstrates the applicability of the proposed method. Keywords—mechanical system reliability; correlative coefficient; system reliability model; performance function; Sensitivity 摘要：本文介绍了一种通用的机械系统可靠性建模和分析方法，它考虑的失效模式的相关性。首先，这代表了故障模式的表现方式基于FORM（一阶可靠性方法）线性化，以及这些功能的相关系数矩阵的计算方法。然后，采用PFTA（概率故障树分析）方法建立系统可靠性模型。最后，有效的算法如G-FOMN（一般一阶方法）被用来量化系统的可靠性，系统的可靠性指标的相对于每个故障模式的敏感性，以及平均值和每个标准偏差随机变量也被计算出来。工程实例证明了该方法的适用性。 关键词：机械系统的可靠性;相关系数;系统可靠性模型;性能功能;灵敏度 I. INTRODUCTION Existing approaches for mechanical system reliability analysis are usually based on the assumption that all failure events of the system are statistically independent, or just take reliability of the weakest element in the system as representative of the system reliability. But the fact is that correlation exists among