Reliability Modeling of Systems with Protective Auxiliary Components under Imperfect Inspections

Systems with protective auxiliary component are common in engineering industry. The auxiliary components in these systems play an essential role to protect the main components from severe environment impact, however, dependence between the main and auxiliary components are usually ignored in most existing literatures. Besides, failures of auxiliary components are hidden in most systems since they do not halt the system. Therefore, inspections are necessary. In most existing studies, inspections are assumed to be perfect, which is not consistent with the reality. In this paper, a new reliability model is developed for systems with dependent main and auxiliary components under imperfect inspections. Some important indexes, such as system reliability and availability, are derived by the recursive and matrix methods, respectively. Thereafter, a numerical example is presented to illustrate the results and verify the correctness of the proposed method, in which influences of imperfect inspections are also studied by conducting sensitivity analysis on the inspection accuracy parameter.