Modeling of Degradation in Gas Turbine Engine by Modified Off Design Simulation

Abstract

Legacy turbojet engines suffer degradation in performance with usage. Degradations in engine components show different observable symptoms based on the control mode of the engine. Hence, to accurately model the engine and its degradations, a novel off-design modeling method that considers the control settings of the engine is presented. The improvement in degradation modeling due to the modified scheme is presented in detail. The mathematical model used in the degradation simulation is validated by comparing the model outputs to the engine mounted sensor measurements at various ratings in the engine test bed. The estimation component parameters used in the model through nonlinear gas path analysis and optimisation-based routines is also presented.