Analysis of the Internal Flow Characteristics, Pressure Pulsations, and Radial Force of a Centrifugal Pump Under Variable Working Conditions

In this paper, IS 80-65-160 clean water centrifugal pump is taken as the research object. By comparing the characteristics of internal flow, impeller pressure pulsation and radial force of centrifugal pump under various typical conditions of different adjustment modes, the differential performance of the pump in throttling and frequency conversion adjustment as well as the internal mechanism of energy saving in frequency conversion operation of the pump are obtained. It is found that the maximum amplitude of B4 point is 0.231 under 0.4n(r)-0.4Q(r) condition, which is 0.369 lower than 0.60 under throttle adjustment n(r)-0.4Q(r) condition, indicating obvious optimization. There are similar optimization rules in flow conditions corresponding to different adjustment modes. From the analysis of the radial force of the impeller, it is found that the pulsation amplitude under the design condition is 17.83 N. During throttling adjustment, with the increase of the flow adjustment range, the main pulsation frequency remains unchanged, the pulsation amplitude gradually increases, and the pulsation peak value reaches 26.42 N under the 0.4n(r)-0.4Q(r) operating condition. When frequency conversion adjustment is adopted, as the speed gradually decreases, the main frequency and peak value of the pulsation gradually decrease, and the peak value of the pulsation is less than 4.5 N under the working condition of 0.4n(r)-0.4Q(r), reaching the minimum value. Compared with the flow conditions corresponding to throttle adjustment and frequency conversion adjustment, frequency conversion adjustment can effectively reduce the amplitude of radial force pulsation of the impeller, which is beneficial to the stability of the pump.

Automated summary

In this study, the IS 80-65-160 clean water centrifugal pump is investigated. By comparing the characteristics of flow, pressure pulsation, and radial force under different adjustment modes, it is found that frequency conversion adjustment can effectively reduce the amplitude of radial force pulsation, improving the stability of the pump.