| Compressor as one of the core component of gas turbine,it compress the air through consuming the mechanical work,In order to supply high pressure air to combustion chamber.Compressor has been attracting the attention of scholars both at home and abroad,because the compressor performance directly affects the efficiency of gas turbine,work stability,and specific fuel consumption,etc.The limitation of early stage design which based on the uniform inlet condition is becoming larger,no longer suitable to the high performance engine design.Because the compressor work in non-uniform import conditions most of the time,which makes the efficiency and pressure ratio decline.They have the severe affects on Performance and aerodynamic stability of axial flow compressors.Therefore,the import non-uniform problem has become one of the key research directions in the field of compressor.Understanding the internal flow mechanism and grasping the response mechanism of the flow field structure change to the non-uniform flow is significant and realistic to the design system of compressor.In this paper,author studies a 2.5 stage compressor.For the flow field of compressor whose inlet pressure uniform and non uniform.The author studies it through the method combining the numerical simulation with experiment text.The main content of this article revolves around the following aspects:1.The establishment,calculation and data processing of the model.Geometric model is set up and the grid division is completed by using AutoGrid5 modules of NUMECA software.It gets the control equations,discrete method,and numerical calculation method of the CFD method by using the FINE/Turbo module.Through the CFView module,compressor internal pressure field,velocity field,temperature field and other parameters is obtained.2.To test the reliability of numerical simulation,a performance experiment of compressor compares with the results from CFD software is necessary.3.Study on Aerodynamic Characteristics of Compressor under Uniform Pressure Intake Condition.The compressor is simulated with eight kinds of speed(0.5n,0.6n,0.7n,0.8n,0.9n,0.95 n,n,1.05n).The thesis gets the compressor performance parameters in the design condition and other conditions through the numerical simulation.And the change of the internal flow field under different rotational speed is analyzed.4.Influence of non-uniform Pressure Intake on Pneumatic Characteristics of Compressor.The compressor is simulated under five different inlet pressure non-uniformity.It obtains the change of the surge margin and the recession of mass flow rate,efficiency and pressure ratio.Also the change of the internal flow field under different inlet pressure non-uniformity is analyzed. |
