Gas turbine transient performance modeling for engine flight path cycle analysis

The growth in competitiveness in airline industry has called for more advanced tool to \nestimate the operating costs. Engine maintenance costs are an important decisionmaking \nelement during airline fleet selection judgment. Long term observation in \naerospace led to the development of engine maintenance costs calculators based on \nempirical correlation. But the possibilities of empirical model application for future \nengines without prior operational data are limited. \nA physics-based tool to estimate the life of the engine components and predict the \nshop visit rate requires the variations of thermodynamic parameters over the flight \npath. High fidelity engine models are simulated using an engine performance program. \nA test program designated for design, off-design and transient performance simulation \nfor simple turbojet layout gas turbine engine has been programmed and tested. The \nknowledge gained from program coding was used to generate more robust transient \nperformance code implemented to Turbomatch. Two transient methods have been \ntested: The rapid transient performance method and the thermodynamic matching \nmethod. The tests showed greater robustness and stability of the second method, \nwhich has been finally adopted for the program. For industrial engine configuration \nand for future novel engine cycles the heat-exchanger dynamic response model was \nimplemented and tested. \nCreated tool was demonstrated on short-haul study of engine flight path analysis. \nTogether with the aircraft model, the tool produced variations of parameters needed \nfor the lifing algorithm.