Vol. 38, No. 1 (2015) (11)

Minimizing Redundancy Allocation Problem Based on Non-overlapping Subsystems

D. Hossen† & P. Y. Dahlan‡*

†Department of Mechanical Engineering, School of Engineering, Persian Gulf University, Boushehr, 75168, Iran
‡Indian Institute of Social Welfare and Business Management, Calcutta, India, *Email: dahlan@yahoo.com

ABSTRACT: The present paper considers the allocation of redundancy to coherent systems with competing choices of system-components, while minimizing the total cost of adding redundancy, subject to a predetermined level of system reliability. Use of redundancy to enhance system reliability increases the total design cost. This paper resolves a cost minimizing redundancy allocation problem (CMRAP) in a coherent system, where total cost of using redundancy is minimized subject to a given reliability target. A numerical example has been included to explicate the method. A sensitivity analysis has been done to study the sensitivity of the optimal solution, related cost and the gain in system reliability to the reliability targets. It has been observed that the solution is robust within a group of reliability targets, but they are sensitive from one group to the other. No fixed form of component life distribution has been assumed here, which added enough flexibility in application of this method.

Keywords: Coherent system; Cost minimization; Redundancy; Reliability target; System reliability.