Study On Hydraulic Design And Structural Gap Performance Of Stock Pump

At present,the research of stock pump is mainly concentrated in the semi-open impeller stock pump.The research on the gap between impeller and wear liner is mainly about the gap between semi-open impeller and front wear liner in China.This paper makes a small contribution to this field.The size of the gaps between the impeller and the front and rear wear liner of the stock pump has a significant effect on the performance.The wide gap causes the hydraulic efficiency to decrease,and the narrow gap increases production and maintenance costs.Therefore,it is a great significance to select the correct gaps between the impeller and the front and rear wear liner to help the pump to run efficiently and improve the efficiency of the stock pump,and to reduce the energy consumption and costs.In this paper,the speed coefficient method is used to redesign the main flow parts of the stock pump,and then make the 3D modeling,grid division and numerical simulation analysis.Make unsteady numerical simulation by designing five different impellers and the gaps between the front wear liner and the rear wear liner.The simulation results show that the designed stock pump will reach the maximum efficiency when the gap between the impeller and front wear liner is 0.75mm,and the gap between the impeller and rear wear liner is 0.5mm.And these gaps meet the actual requirements of processing,production and application.In this paper,a complete cavitation model is used to simulate the designed stock pump.To simulate the pressure pulsation and cavitation performance of each monitoring points by five different gaps between the impeller and the front and rear wear liner.The pressure pulsation characteristics are analyzed through the time domain map of the monitoring points,when the impeller and the gaps between the front and rear wear liner are wider,the pressure pulsation characteristic of the stock pump can be improved effectively.When the NPSH is 1.5m,by analyzing the effect of the impeller on cavitation characteristics of the stock pump,the cavitation performance of the model stock pump gradually improved with the increase of the gaps.The model pump was tested at the design point.The experimental results are consistent with the design target parameters and numerical simulation.It is proved that the model stock pump designed in this paper is advanced and numerical simulation is reliable and accurate.Due to the limited time,this paper only simulates the research and the cavitation performance on the different gaps between the impeller and front and rear wear liner of the designed model stock pump.The follow-up study should continue to improve the other pump models of different capacity and head.