Effect of the Gap Matching Relation on the Pressure Pulsation Characteristics at Blade’s Surface of the Multiphase Pump

Abstract

The pressure pulsation characteristics of the blade’s surface have an impact on the lifespan of the multiphase pump impeller. To explore the influence of the gap matching relation on the pressure pulsation characteristics at blade’s surface of the pump, the axial clearance coefficient (ACC) between the impeller and diffuser and the relative tip clearance of the impeller were defined. By combining of numerical simulation and experiment, the pressure pulsation characteristics at blade’s surface of the single pressurization unit of the pump were studied under different gap matching relations. The results show that the size of tip leakage flow and the strength of rotor-stator interaction caused by different relative tip clearances have a decisive influence on the pressure pulsation characteristics in the impeller. With the increase of tip clearance, the internal flow field distribution law was greatly changed, which had a great impact on the pressure pulsation peak-to-peak value and dominant frequency amplitude of the suction surface. In addition, the pressure pulsation characteristics of the diffuser were mainly affected by the strength of rotor-stator interaction. When the strength of rotor-stator interaction weakened, the amplitude of the dominant frequency pulsation was decreased by degrees. As the ACC increased, the variation of the pressure pulsation peak-to-peak value and the dominant frequency amplitude coefficient were gradually slowed down in the diffuser, and the dominant frequency amplitude of the monitoring points were most sensitive to change in the ACC. The research results can provide a theoretical reference for the optimal design of the multiphase pump blades.