The Influence Of The Compressor Flow Control System On The Safety Of The Aeroengine Performance

Compressor flow control system is mainly composed of Variable Stator Vane(VSV)and Variable Bleed Valve(VBV).Its performance will directly affect whether the engine can work stably and reliably.The requirements for the safety of the engine control system are set out in the Federal Aviation Regulation(FAR)clauses 33.28 and 33.75.In order to evaluate the fault level of VSV and VBV systems in the process of system safety analysis,and to avoid the quantification deficiency in the empirical analysis and logic inference analysis,this paper evaluates the functional risk of VSV and VBV control systems based on the whole engine model.(Functional Hazard Assessment,FHA)analysis to start research work,the results of the study can provide support for the safety assessment of the compressor flow control system.The main research content of this article is as follows:Firstly,based on the characteristics data of engine components,a steady-state machine model of a large bypass ratio turbofan engine was established using the component method,and the validity of the model was verified.Firstly,the general characteristics data of aero-engine are obtained by GSP software.The components of a certain engine are obtained by scaling,which forms the basis of modeling.Secondly,based on the Matlab/Simulink simulation platform,a complete engine model of a certain engine was built using the component method.Again,the Newton-Raphson method is used to solve the nonlinear equations formed by the aeroengine power balance and flow balance,and a certain engine steady state model is obtained.Finally,the steady-state solution results of different steady-state points are compared with test data to verify the validity of the model.The engine steady-state engine model constructed in this section lays the foundation for subsequent research work.Secondly,based on an established engine model,the VSV system's adjustable stator vane angle and VBV system variable valve opening were simulated.Based on the model of a certain engine,VSV and VBV modules were added respectively.The simulations were carried out to determine the effects of different stator vane angles and different bleed air valve opening degrees on the engine performance parameters during takeoff,cruise,and idle conditions.The results are VSV and VBV.The system's FHA analysis provides a simulation basis.Thirdly,based on the simulation results obtained,FHA analysis and research of VSV and VBV control systems were carried out.By sorting out the FAR airworthiness regulations and the Society of Automotive Engineers(SAE)documents on the requirements and recommendations of the FHA work,the failure impact levels of the VSV and VBV control systems were determined and the FHA analysis results were finally obtained,thereby implementing the compressor.The system security analysis of the flow control system provides reference and support.