Numerical And Experimental Research On The Effects Of Variable Inlet Guide Vanes On Compressor Stability Boundary

As one of the key components of gas turbine,the performance of compressor has great influence on the whole gas turbine system.The performance of the compressor is affected by unstable flow such as surge and rotation stall.Surge not only restricts the performance,but also dose harm for the safety of the compressor seriously,therefore,various means are used to expansion the stable operation of compressor.Variable inlet guide vane has become an important way to expand the compressor stability.In this paper,numerical simulation of a 2.5-stage transonic compressor is carried out,and the stability of the compressor under different guide vanes' installation angles is compared and analyzed as while as the internal flow changes of compressor.The main research is as follow :1.Study on internal flow of compressor.By using NUMECA commercial software,the whole working condition of the compressor are simulated.The mach number,static pressure and air flow angles of the compressor were analyzed under the three typical working conditions(design condition,stall condition,choked condition).And the flow separation of the blades at different stages of the compressor instability was explored,which laid the foundation for the next research.2.Study on compressor's performance based on gap height of guide vanes.Because of the existence of the gap of the variable inlet guide vanes,the change of the characteristic curve and entropy of the compressor is compared in difference of the guide vane gap.The effect of the gap height on the performance of the compressor is simulated.3.Study on effect of different guide vanes installation angle on compressor performance.Based on the installation angle of the primary vane,and multi-installation grid was developed,and the effect of different angle of vanes on the characteristics of the compressor was studied as while as the Influence of compressor surge boundary.At the same time,the internal flow of the stall point at the design speed of each installation angle was compared,and the effect of the transferable blade on the instability point and the mechanism of improving the anti-surge capacity of the compressor was studied.4.Study on characteristics of compressor at low speed.Comparing the difference of inlet flow angle of compressor blades at low speed and design speed,the internal flow of compressor at different speeds are analyzed and compared.The anti-surge effect of rotatable vane at non-designed speed is compared.5.The test bench of the compressor is sat up,and the measuring methods of various performance parameters are introduced,which pave the way for the next experimental research.