Influence Of Spanwise Continuous Bumps On Aerodynamic Performance Of Transonic Compressor

As one of the three core components of gas turbines,the compressors will continue to develop in the direction of high pressure ratio and high efficiency.As the load level of the compressor continues to increase,the internal flow gradually changes from subsonic speed to transonic speed.For transonic compressors,due to the supersonic zone inside the compressor channel,the accompanying shock-related losses have become one of the main sources of aerodynamic losses in the transonic compressor.Therefore,if the shock wave intensity can be reasonably weakened,the internal wave system structure of the compressor can be improved,and the shock wave loss and the boundary layer separation loss induced by the shock wave can be an effective way to improve the compressor performance.In this paper,a typical transonic compressor rotor NASA Rotor 37 is selected as the research object.By adding a bump with different flow and spanwise parameters on the suction surface of the rotor,the prototype rotor and the bump rotor are numerically simulated using NUMECA software.By analyzing the changes of aerodynamic performance and the limit streamlines of the flow field near the wall,relative Mach number,static pressure,entropy and other parameters,the control effect and flow improvement of different flow direction parameters and spanwise direction parameters on shock waves are compared and analyzed.It is found that the bump can effectively weaken the shock wave intensity and restrain the interaction between the shock wave and the boundary layer,so as to reduce the separation loss,improve the flow condition,improve the efficiency of the compressor rotor and enhance the stall margin of the rotor.Numerical simulation results show that at 100% of the design speed,the starting position of the flow direction of the bump plays an important role in the intensity and position of the shock wave.When the front edge shock wave is incident on the windward side of the bump,the bump has the best control effect on the shock wave;the length of the flow direction has little effect on the intensity and position of the shock wave;As the height of the flow direction increases,the control effect of the bump on the shock wave is enhanced,but it will also cause additional flow losses in the tip and root of the blade.Therefore,it is necessary to study the spanwise parameters of the bump.When the spanwise length is appropriate,the bump can effectively control the shock wave,while reducing the impact on the flow of the rotor root,and further improving the efficiency of the rotor.When changing the spanwise continuity of the bulge,it is found that the performance improvement and shock control effect of the spanwise discontinuous bump rotor is significantly weaker than that of the spanwise continuity bump rotor.At 95% and 110% design speeds,the numerical simulation was carried out for the continuous full blade height bulging rotor and the continuous partial blade height bulging rotor in the spanward direction.It is found that at 95% design speed,the bump of the blade height of the spanwise continuity part improves the performance of the rotor better than the bump of the full blade height of the spanwise continuity.At 110% design speed,the bump with full blade height in spanwise continuity improves rotor performance better than a bump with blade height in spanwise continuity part.However,the bump rotor with spanwise continuity part blade height at 95% design speed,100% design speed,and 110% design speed all increase the efficiency and stall margin compared to the prototype rotor,and its working condition adaptability is optimal.