Developing a new model for availability of a series repairable system with multiple cold-standby subsystems and optimization using simulated annealing considering redundancy and repair facility allocation

Redundancy technique is considered as a way to enhance the reliability and availability of a system. This paper models availability of a repairable system with multiple subsystems in which the involved components follow cold-standby strategy. The goal is to find the optimal number of repairmen and redundant components in each subsystem for optimization of steady-state availability subject to weight, cost and volume constraints. Repairmen allocation is a new variable in redundancy allocation problem for repairable systems. This problem belongs to nonlinear programming. Due to complexity and time limitation, a simulated annealing algorithm is proposed to solve the problem. Finally, computational results of three cases with various subsystems are illustrated to prove the efficiency of the proposed algorithm.