The Research On The Internal And External Characteristics Of Centrifugal Pump Based On Bionic Micro-groove Modification

As an important fluid transfer equipment,centrifugal pumps are widely used in various sectors of the industrial system,so improving the performance and energy utilization of centrifugal pumps has been an important research topic in this field.Therefore,this study is inspired by the special micro-groove structure on the surface of shark skin,based on the structure of the impeller cover of the original model pump(OMP),different shapes of bionic micro-groove modification(BMGM)are designed,and the pressure pulsation and energy loss performance are investigated in two aspects The improvement of the flow in the pump was analyzed,and the main research contents are shown as follows:(1)Construction of impeller cover plate model.With the bionic principle as the theoretical premise,five bionic micro-groove structures were designed and arranged on the inner surface of the original impeller cover plate inside the original model pump OMP,named BMGM-1,BMGM-2,BMGM-3,BMGM-4 and BMGM-5 respectively.(2)Verify the accuracy of the adopted numerical method and the established geometric model of the original model pump.The experimental external characteristics performance of the original model pump was verified with the numerical simulation results,and it was found that the obtained external characteristics performance curves were in good agreement,where the error range of the head curve was 1.6%-7%,and the error range of the efficiency curve was only 1.1%-3.2%.(3)The external characteristic performance and internal flow field information of the bionic model pump and the original model pump were compared and analyzed.Based on the results of the constant numerical simulations of the bionic model pump and the original model pump,it is found that the performance of the bionic model pump is better than that of the original model pump,among which the performance of the BMGM-5 is most obviously improved,with its head and efficiency increasing by 5.6%and 10.3%,respectively.At the same time,further analysis of the velocity flow line,static pressure coefficient and turbulent kinetic energy distribution in the six model pumps showed that the bionic micro-groove structure not only homogenized the pressure distribution in the internal flow field,but also reduced the vortex intensity in the flow field and turbulent flow frequency in the impeller runner,which improved the stability and energy loss performance of the flow in the model pump,with the most obvious improvement in BMGM-5.(4)Comparison and analysis of the pressure pulsation characteristics in the bionic model pump and the original model pump.Based on the non-constant numerical simulation results of the bionic model pump and the original model pump,the time and frequency domain distributions of pressure pulsation in the middle of the impeller runner,the outlet and the interference area between the runner outlet and the worm wall are analyzed and studied.especially obvious.Among the five bionic model pumps,the BMGM-5 model pump has the best improvement effect,with the highest reduction of pressure pulsation up to 28.648%.(5)Comparison and analysis of the energy loss characteristics in the bionic model pump and the original model pump.Based on the non-constant numerical simulation results of the five bionic model pumps and the original model pump,the energy loss characteristics in the impeller runners of the six model pumps were compared and analyzed by using the vortex energy transport equation and the total vortex energy analysis method,and it was found that the total vortex energy of the bionic model pump(BMGM)was lower than that of the original model pump(OMP)in one rotation cycle.4.1%,while the reductions of BMGM-2,BMGM-3,BMGM-4,and BMGM-5 are all higher than 30%.Among them,BMGM-5 has the largest reduction Therefore,the BMGM-5 bionic microgroove can effectively improve the situation of large energy loss in the impeller flow channel due to the large scale vortices formed by turbulence constantly colliding with the flow channel walls,and improve the energy utilization in the model pump to a certain extent.