Axial Compressor/Fan Blade Aerodynamic Optimization Design Based On A Quasi Three-dimenslonal Approach

During the course of the axial compressor/fan blade aerodynamic design with a quasithree-dimenslonal approach, losses prediction is the major deficiency of throughflow design on the S2flow surface, which are usually got through test data and empirical relationships, and difficult to beapplied to any blade design in general. In this dissertation, the loss model is replaced by the radialdistribution of total pressure loss with the Numeca3D numerical modeling, which originates from theblade of the first round aerodynamic design. The3D flow effects such as annlus wall boundary layer,radial mixing are concerned in the loss data. So with a second round blade design done, the profileson the S1flow surfaces will adapt to the3D flow to some extent. Then the blade with perfectaerodynamic performace will be obtained, which satisfies the objective of the throughflow designsimultaneously.Based on the existing achievement of laboratory, the aerodynamic optimization design of profileson the S1flow surfaces is applied to the quasi three-dimenslonal process. The optimization isconducted after the original profile aerodynamic design with direct question method. With theaerodynamic optimization design, the profile modification based on artificial expertise is replaced bythe process of numerical optimization, which reduces dependence on the profile design expertise,shortens the design cycle.An axial compressor/fan blade aerodynamic optimization design process based on the quasithree-dimenslonal approach is developed with the researches above, and a low aspect ratio radialstacking rotor blade of axial compressor first stages is designed. With the total pressure ratio objectiveof2.07and the mass flow-rate objective of6.3kg/s, the rotor designed shows the isentropic efficiencyabout90%, and reaches the stall margin of15.5%. The proximity of the objective from throughflowdesign is satisfactory also.The3D stacking line optimization design of the designed rotor blade is further conducted. Theresults show little changes on the total pressure ratio, mass flow-rate of the design point and the stallmargin, and the increase of less than0.8%on the design point isentropic efficiency. But morereasonable distribution of3D flow field in the rotor passage and more gradual changes of the bladeload distribution are obtained.