Optimization for First Stage of Multistage Pump Based on Response Surface Methodology

To improve the efficiency of a multistage centrifugal pump at design point, the response surface methodology was applied to construct an approximation function between the design-point efficiency of the first stage in multistage centrifugal pump and the design variables of the impeller. First, important geometric parameters are selected as factors of a one-factor experimental design. Four parameters that had greater influence on the hydraulic efficiency were screened out from the simulation results using parameter sensitivity analysis. The optimal design points for each level of the parameters were then determined by central composite design and the response surface analysis method. The efficiencies of the impeller schemes generated in the Design-Expert software was executed with CFD. The effects of the single parameters were analysed, and the approximation model solved to find the optimal parameter combination that improve the efficiency by 3.62% at design point. And the inner flow was improved in high flow rate condition.