Aerodynamic Design Of Industrial Axial Compressor Blades

For modern industrial axial compressor design, it’s the future development tendency that extending the flow-range of operation and increasing the stability operation margin under this premise of assuring high efficiency at design point. The main task of this paper is to design the blades of industrial axial compressor based on S1/S2 Stream surface theory and improve the performance of the design and off-design points with multi-point optimization design method.Firstly, S2 stream surface flow calculation results with lab and the three dimension results which calculated by NUMECA software have better consistency by mean of comparison and analysis. The results proved that it can be suitable for the design of subsonic axial flow compressor. The appropriate design parameters are chose by analyzing the effect of the hub-shroud ratio, tip rim speed and the pressure ratio of single stage for the performance of rotor and stator.Secondly, rotor and stator blades of single-stage compressor are designed based on the results of S2 stream surface flow calculation. Design and off-design characteristic is get by S1 stream surface flow field calculation. For the question that the stator blades lack sufficient stability margin, blades geometry is modified with direct method. The stall margin is increased by more than 4 degree for stator blades of different blade height. The S1 stream surface flow field calculation results of rotor and stator blades are consistent with the results calculated in three dimension environment. So, for the design of subsonic axial compressor, S1 stream surface calculation results can simulate the three-dimensional flow characteristics in three dimension environment.Thirdly, the S1 stream surface is optimized at design and two off-design points with multi-point optimization design platform designed by the lab. The optimization results show that the loss of S1 stream surface blade decrease more or less and the range of low loss is expanded. Meanwhile, The stall margin is increased by more than 1 degree.Finally, the three dimension blades are obtained by stacking initial and optimize profile respectively. Design and off-design characteristic at design speed of single-stage compressor is get by three dimensional viscous flow simulation. At design point, the rotor efficiency is increased by 0.17% and the total pressure recovery coefficient of stator is raised to 0.997 from 0.996. The stability margin of single-stage compressor is increased by 7.1%. The basic method of three repeating stages is developed and a design is carried out to verify the method. The result that repeating stages design total pressure ratio is 1.517 and efficiency is 91.7% meet the design goals. Through the analysis for the calculation results of four and five repeating stages demonstrates that the more stages, the better repeatability. But, due to meridian plane is convergent more, the efficiency of subsequent reduces more at the end wall region.