Multiobjective optimization of incidence features for cascade

MultiBezier curve was adopted to describe the cascade of the axial flow compressor in parameterized form. By taking the Isight software as optimization platform, the calculation program of the S1 surface was adopted to calculate the flow field, and the improved nondominated sorting genetic algorithm (NSGAⅡ) was employed to conduct the multiobjective optimization of the features of incidence for the cascade of the middle section of rotor and stator of Stage35, which was onestage axial flow transonic compressor from NASA. The optimization goal was to reduce the total pressure loss coefficient in the whole range of the incidence and widen the adaptive range of the incidence. The lowest total pressure loss coefficient and the difference between the relatively highest and the lowest point of total pressure loss coefficient were set as the optimization objective functions. The flow rate of the cascade constant was set as constraint. Results indicated that the optimization greatly reduced the total pressure loss coefficient of the cascade of the middle section of rotor and stator, and widened the range of the incidence of the middle section of rotor and stator by 5° and 3° respectively.