Economic analysis of a water process system with provision of non-switching and online repairs on minor faults

The paper investigates a stochastic model developed for an industrial process water system on the basis of observation taken from Panipat Thermal Power Plant, Panipat. The system comprises of several redundant and non-redundant subsystems wherein the redundant subsystems are of two types, namely 1-out-of-2 (Type-I) and 2-out-of-3 (Type-II). The system goes to complete failure due to a fault in non-redundant subsystem whereas it goes to partial failures due to a minor fault as to avoid the generation losses switching of the redundant subsystems is not carried out. However in case of occurrence of major faults in a redundant subsystem, switching of the subsystem is automatic and instantaneous. Further on partial failure, the repairman first inspects the system to judge which subsystem has the minor fault and accordingly carries out the online repair of the subsystems. For the model, various measures of system effectiveness are obtained using Markov process and regenerative point technique. Profit incurred to the system is also computed. The reliability and cost analyses of the system are presented through graphs for a particular case.