Fuzzy reliability analysis of DFSMC system in LNG carriers for components with different membership function

Abstract

The purpose of the present study is to analyse the fuzzy reliability of dual-fuel steam turbine mechanical propulsion conventional (DFSMC) system of LNG carriers for components with different membership function by applying Tω(weakest t-norm) based generalized fuzzy lambda-tau (TBGFLT) technique. TBGFLT technique applies fault-tree, Lambda-Tau method, different membership functions, α-cut and the weakest t-norm (Tω) based approximate fuzzy arithmetic operations for evaluating fuzzy reliability of the system. The computed results have been compared with results obtained from four other fuzzy reliability techniques. This comparative study concludes that TBGFLT reduces growing phenomenon of fuzziness at any confidence level when system components' follow different membership function. System long run reliability and availability, sensitivity analysis and its critical components’ ranking have also been conducted for analysing system behavior to improve its performance. Based on the results, some influential suggestions have been drawn which may be helpful for maintenance personnel to design and execute some action plans for improving system performance under vague environment.