Analysis on Sensitive Parameters of Full-3D Optimization of a Centrifugal Impeller
This paper employs the Sobol sensitivity analysis method to extract aerodynamic per-formance sensitive parameters under 114 control parameters for centrifugal impellers.By comparing the internal flow fields of the baseline and optimized impellers,this research examines the basis and rationality of the flow mechanism hierarchy for the full three-dimensional optimization results of centrifugal impellers.The findings indicate that the sensitive parameters for blockage flow are located near the throat of the impeller,demonstrating that sensitivity analysis methods can identify key control parameters for specific aerodynamic performance.The sensitive parameters for pressure ratio are distributed at the trailing edge of the blades.Modification of the optimized impeller's trail-ing edge shape has improved the uniformity of the relative flow angle at the diffuser inlet without altering the relative pressure distribution along the span at the impeller outlet;The sensitive param-eters for efficiency are concentrated at the leading edge of the main blade.The optimized impeller's control over the convexity and concavity of the blade leading edge has reduced shock and secondary flow losses,achieving an improvement in efficiency.After further research into the high-order in-teractions of control parameters,sensitivity analysis methods can be used to reduce the number of control parameters and increase the speed of the full three-dimensional optimization approach.