考虑耦合关系的故障模式消减方案决策

针对目前复杂产品研制过程中故障模式消减方案确定主要凭经验,未考虑故障模式之间的耦合关系问题,建立了考虑耦合关系的故障模式消减方案决策过程.首先,提出了故障模式关联集(FMCS,Failure Modes Correlation Set)的概念,并运用演绎理论给出了FMCS的确定方法.其次,根据故障模式消减后其发生概率变化,构建了不同层次产品可靠性指标受影响的模型,并以此为依据,给定面向可靠性指标实现的故障模式消减方案决策方法.最后,以某型直升机燃油系统故障模式消减为例验证了上述方法及模型的可行性,初步证明了可靠性定量指标与定性设计之间存在明确的量化关系,可通过其控制故障模式消减,达到以最少资源消耗和较短研制周期实现满足设计要求的产品的目标.上述方法及模型具有实用性,可进一步在实际工程中推广应用.

Decision-making of failure modes mitigation program considering coupling relationship among failure modes

During the development stage of complex products,failure modes mitigation program often decided by experience,without considering the failure modes’ coupling relationship.Aiming at solving this problem,a decision process of failure modes mitigation program was proposed.Firstly,a new concept of failure modes correlation set(FMCS) was presented,including the determination approach based on deductive theory.Secondly,according to changes about failure modes occurrence probabilities,models depicting the varying relationship between failure modes mitigation and quantitative achievement of reliability were constructed to decide failure modes mitigation sequence orienting to the requirements achievement.Finally,a case study of helicopter fuel system demonstrated the feasibility of approaches and models,proved the existence of the relationship between reliability quantitative achievement and qualitative design,and the failure modes mitigation could be controlled orienting to the quantitative achievement of reliability availably to satisfy the design requirements with minimal cost of resources and time.Furthermore,the approaches could be applied in real engineering scenarios due to the practicality.