Experimental Study on Pressurization Property of Three-stage Centrifugal Multiphase Pump on Gas-liquid Two-phase Flow Conditions

The pressurization property of the three-stage centrifugal multiphase pump under the condition of water and air-water two-phase flow was studied experimentally. For single-phase water, the pressurization performance agrees well with the designed values. The two-phase pressurization performance presents different stages as a result of gas entrainment. At three rotational speeds (3500, 4000, 4500 r•min^-1), the gas flow rate was maintained constant. With the decrease of liquid flow rate, the two-phase pressurization gradually deviates from the single phase. With the increase of gas volume fraction, the two-phase pressurization can be divided into three regions: discrete bubble region, bubbly flow region and long-bubble region at constant liquid flow rate. The two-phase pressurization is mainly dependent on the rotational speed and gas volume fraction, and independent with liquid flow rate for the liquid flow rate range 10 ~26 m³ •h^-1. The equivalent flow rate and head on gas-liquid two-phase condition were defined. Under single-phase and two-phase conditions, the pumps meet the affinity law well, which provides a reference for relevant design.