The Research On The Parametric Design And The Internal Flow Field Simulation Of Centrifugal Pump

Centrifugal pumps are widely used in fire-fighting,shipping and irrigation industries.But the domestic pumps have lower pumping head,big loss of energy and lower stabilities in comparison with same specifications of imported pumps.China has large demand of high-performance centrifugal pumps.But most of the pumps are rely on imports,which is expensive and has technical constraints.This situation has a serious impact on the development of the centrifugal pump industry.In this paper,the research object is single-stage ingle-suction centrifugal pump.In order to improve the centrifugal pump properties,shorten development period and reduce costs,this paper applies researches on the parametric design,numerical simulation and optimization design as below:On the basis of the velocity coefficient design method of centrifugal pump,MATLAB is used for parameterized design of the impeller,pressurized water chamber and suction chamber in this paper.In order to make it convenient to man-machine interaction,interface is designed.After entering the original parameters,geometric parameters and the range of impeller parameters can be obtained.This process is based on the developed program.The data points of each flow-passing component are saved.3D model of the flow-passing component is obtained by importing data points through Pro/E.ICEM CFD is used for unstructured meshing of the model,CFX is used for numerical simulation of the centrifugal pump.The pressure cloud and the velocity vector under different flow are analyzed,the distribution of pressure and velocity vector are confirmed.By numerical simulation on centrifugal pump with different impeller structural parameters,the external characteristic curves can be plotted,the impacts of the structural parameters on head,shaft power and efficiency can be confirmed according to the result,which lays foundation for optimization design of centrifugal pump.Based on MATLAB software,genetic algorithm is used in this paper.With the objection function of maximum head and minimum energy loss,and with the range of impeller structural parameters determined as restrictions,the M file is programmed.This M file is compiled for determining the optimal combination of impeller structural parameters by optimizing the impeller outlet diameter,impeller outlet width,blade inlet diameter,blade outlet angle,blade inlet angle and the number of blade.The optimization results are verified by simulation analysis.Compared with the initial design scheme,the centrifugal pump head is increased by 1.4m and the efficiency is improved by 1.2% when the flow rate is 80L/s.