Model And Simulation On Technology Of Active Stability Control For Aeroengine Based On Non-constant Speed Condition

Compressor is an important component of aeroengine.While,according to the compressor operating principle,for the increase of pressure ratio and decrease of compressor flow,the compressor will go into unstable working area where stall and surge always happen,which will restrict the stable work area of compressor and affect aeroengine safety work.In order to make full use of compressor performance potential,and extending compressor stable operating range,compressor active control become the research hotspot of engine domain.Compressor dynamic model building is promise of Active Stability Control.Moore-Greitzer model can describe compressor interior flow and pressure variations in unstable operating states,but it is limited to constant speed conditions.While compressor speed is changing,the model is of no use for unstable performance analysis.To solve the problem,compressor dynamic model under non-constant speed is conducted.B-parameter become a new state parameter in the model by introducing rotor momentum balance equation to describe the speed variation.Simulations are conducted and influence of parameter variations on compressor dynamic performance in acceleration process is analyzed.Simulations show that when throttle opening decrease,compressor is more likely come into unsteady operating area.Meanwhile,the larger acceleration ratio is,the easier the compressor goes into instability.According to the Active Stability Control,in order to restrain flow disturbance in compressor,it is necessary to acquire flow coefficients at discrete positions in circumferential direction of the compressor annulus.A distributed compressor dynamic model under non-constant speed is established through discrete Fourier transform.Simulation results show that the model is capable of capturing compressor stall inception transient behavior at discrete positions in the circumferential direction of the compressor annulus.The distributed compressor dynamic model under non-constant speed provides basics for Active Stability Control algorithms design and application of actuator devices.In order to meet the requirements of Active Stability Control,air injector model was conducted to serve as the actuator.The distributed compressor system model under non-constant speed with air injector was established.Simulation show that stall and surge which appeared in compressor acceleration process can be suppressed through air injection.Inlet distortion has always been one of the major concerns in order to maintain a safe and efficient operation of aeroengine.Inlet distoration causes the nonuniform flow come into compressor.Pressure rise will decrease and the compressor gets into unstable operation area easier.Based on compressor model conducted,influence of is inlet distortion is analyzed.And simulation show that Active Stability Control has a positive effect on unstable dynamic control that caused by inlet distoration.