Fluid-structure Coupling Analysis And Parameter Optimization Of Plastic Lined Pump Structure

Pump is used widely in everywhere,which have an important position in the fields of agriculture and industry.In recent years,with the development of chemical industry,the requirements of corrosion resistance and temperature of centrifugal pump are more and more high.The plastic lined pump is widely used in chemical industry because of its excellent corrosion resistance and no temperature rise.With the wide application of plastic lined pump,the research on the plastic lined pump has been paid more and more important.The structural parameters of the pump are the key factors in determining the efficiency of the pump.To ensure the efficiency of the centrifugal pump at the same time to ensure its stability.Cavitation attack is an important cause of breaking the stability of centrifugal pump.In addition,due to deformation of the impeller will cause impeller clearance changes.When the gap is too small,it is very easy to cause the impeller wear,the pump caused by broken ring,so that the pump life is affected,when the gap is too large,there will be more leakage and low efficiency.In view of this,this paper has made a study on the efficiency of the lining pump and the reduction of cavitation damage.The structural parameters of a centrifugal pump were calculated according to given working conditions of the plastic lined pump with velocity-coefficient method.With the parameters,CAD software was used to construct 3-D entity models for components of the plastic lined pump.CFD software was used for numerical simulation of the flow field of the centrifugal pump;the pressure nephogram,the speed nephogram and steam volume fraction diagram of the centrifugal pump movement were obtained.The efficiency of the cavitation and the cavitation location is predicted.Based on comprehensive consideration of efficiency and cavitation of the centrifugal pump,the inlet diameter Dj,outlet width b2,the outlet angleβ2and the leaf number Z were adopted as the four factors for an orthogonal test.The orthogonal test was completed and range analysis was conducted on the test result to achieve the order of impacts of different structural parameters on evaluation indexes of different optimized directions and the influencing conditions,and the rationality of the model is verified by simulation.An objective function with a maximal efficiency and a minimal net positive suction head(NPSH)and a unifiedobjective function were constructed.In addition,genetic algorithm(GA)was used to conduct multi-objective optimization of the efficiency and the cavitation of the centrifugal pump,therefore,to achieve an optimal parameter combination for the compeller of the centrifugal pump.Based on ANSYS Workbench platform,using the method of fluid solid coupling,the structure of plastic lined pump were analyzed.And the force deformation of the impeller under fluid-solid coupling is obtained.According to the deflection curve established on the impeller,the displacement of the impeller is obtained.In this paper,through the numerical simulation of the internal flow field of the lining pump,the main performance influence parameters of the impeller were selected to improve the efficiency of the lined pump and reduce the residual margin.The range analysis was designed and the results were analyzed.The parameters were optimized by genetic algorithm,and the optimal structure parameters of the lining pump were obtained,which improves the overall performance of the lining pump.The fluid-solid coupling analysis of the lining pump was carried out by ANSYS Workbench software,and the change of the force of the impeller under fluid-solid coupling was obtained.It is instructive for the design of the impeller front cover due to the deformation of the impeller due to the deformation of the lining pump and the design of the width of the vortex chamber.