Perfomance decay simulationof a gas turbine for helicopter propulsion

The effects of turbines blades erosion on the performance of a twin shafts gas turbine engine for helicopter propulsion are investigated by simulation. The engine behavior has been simulated by a mathematical model extensively validated. In order to understand the effects of low (LPT) and high (HPT) pressure turbine stator erosion (increase of throat section and blade thickness reduction according to the experimental evidence from the engine tests from Piaggio Aero Industries), the LPT and HPT performance have been simulated and their performance maps have been obtained with a high level of accuracy. Nine degradation levels have been considered. The introduction of the modified turbine characteristics into the gas turbine simulator has allowed to estimate the degradation effects on the overall engine performance, both in constant fuel mass flow rate (engine on the test bed), and engine running under effective operative conditions (engine installed on the helicopter) with the addition of the fuel control module into the simulator.