Aerodynamic Stability Numerical Simulation Method Study Of Compressor Component Running In Gas Turbine Engine

The surge line of gas turbine engine is an extremely important security boundary. The safety ofaircraft or tactical and technical performance of fighter aircraft is closely related with the surge line.There is now accustomed to describe the surge limit of gas turbine engine by its compressor’s. Withthe requirements of the prediction and assessment the aerodynamic stability on gas turbine engineincreasing, people found that the stability limit of compressor component running in gas turbine isdifferent with the stability limit of component environment’s compressor. As a result, more and moreresearches were focused on this field. Based on the stability limit of the component environment’scompressor, western countries directly corrected the stability limit of compressor component runningin gas turbine by huge test results and experiences. By means of numerical simulations, Russiaestablished the stability model of the whole gas turbine engine. In the model, the stability of gasturbine not only was influenced by the compressor, but also by the other components of engine. Thenumerical simulation method developed by Russia was less dependent on the test while with goodaccuracy. And more important, it is a very good way for depth researching what led to the differenceof stability limit of compressor between gas turbine environment and component environment.Domestic basic research in this field was nearly blank. With the purpose of finding the factorswhich led to the change of the stability limit when compressor running in the gas turbine. A numericalsimulation method was presented for estimating the aerodynamic stability limit of compressorcomponent running in gas turbine engine with uniform inlet flow. The concrete procedure firstlymodeled the gas turbine engine by one-dimension Euler’s equation, secondly coupling with the smallperturbation method linearized the governing equation, finally throttled to the engine and calculatedthe characteristic value of the linear equation set’s coefficient matrix by QR method. If there was atleast one characteristic root with real part, then the gas turbine engine worked unstably. Based on thenumerical result, regarding the compressor running in a turbojet, the aerodynamic stability limit wasless than the component environmental stability limit; regarding Fan in turbine engine environment,the aerodynamic stability limit equaled to the component environmental stability limit; regardinghigh-pressured compressor in turbine engine environment, the aerodynamic stability limit was lessthan to the component environmental stability limit; Coupled with steady state thermodynamic cyclemodel, the paper researched if the performance deterioration of engine influence on the gas turbine’sstability limit.