Aerodynamic Optimization And Highly-loaded Modification Of Transonic Compressor

The tendency of modern compressor is higher compressure ratio and efficiency,the traditional design method cannot match the demand of contemporary turbomachinery,so it's urgent to explore new design and optimization system,thus probing the preliminary optimization design process employing the current advanced theory and concept.The three-dimensional optimization of a two-stage transonic compressor was carried out aiming the maximum efficiency and aerodynamic performance,employing the compatible parameterization method and genetic algorithm integrated with artificial neural network.According to the inner flow characteristic,optimization strategy was formulated,including endwall optimization interated with profile,stacking law optimization and blade profile optimization.After the aerodynamic optimization,the contribution to aerodynamic improvement was calculated in order to analysis the most efficient strategy,thus providing the reference for transonic compressor optimization.Based on the hub endwall and inlet radius of the reference two-stage compressor,highly loaded compressor design was performed to realized the pressure ratio in one stage under the same mass flow rate,in order to reduce the axial length.Current advanced theory and concept was employed to fulfill the preliminary design process,such as low aspect-ratio,low-reaction,endwall constriction and pre-compression.What's more,the tandem stator was beneficial under large bend angle.Preliminary optimization design system which fullly employ empirical 2-Dimentional design and 3-Dimentional numerical optimization,was carried out to fullfill the design with the pressure ratio of 2.4 and efficiency of 85%.Through flow structure analysis was carried out to ensure the reliability of the highly loaded compressor.The designed rotor is reasonable with the aerodynamic load mainly in the tip through shock wave compression;tip leakage flow is well controlled under the endwall contour and tip profile;splike type ratational stall caused by tip leakage flow is detrimental for stable operation range.The result indicates that: the working status of forward blade changes obviously with the incidence,and the incidence range of whole stage almost depends on forward blade alone;aft blade incidence depends on the working status of forward deviation.Flow diffusion and turing in aft blade is weakened because of forward blade trailing edge's piling up,thus the working status of aft blade is improved on condition that the forward blade has large flow seperations.