Experimental Study of Two-Phase Performance of an Electric-Submersible-Pump Stage

Abstract

Summary This paper presents electric-submersible-pump (ESP) -stage performance handling air and water in a laboratory setup. Experimental data gathered shows the effect of volumetric gas flow rate and intake-stage pressure for different rotational speeds. The presence of gas mildly deteriorates the stage performance at low volumetric gas flow rates. A sudden reduction in the stage-pressure increment is observed at this operation condition for a certain critical liquid flow rate, which marks the initiation of surging on the stage performance as mentioned by Lea and Bearden (1982). The surging initiates at lower liquid flow rates as the volumetric gas flow rate increases, which demonstrates the relationship between the surging initiation and liquid flow rate. It is also observed that the initiation of the surging moves toward lower liquid flow rates by increasing the rotational speed or the stage intake pressure. A two-phase stage-performance map was recently introduced, defining boundaries for five pump-performance regimes: homogenous, mild-performance deterioration, performance reverse slop, server performance deterioration, and nil performance (Gamboa and Prado 2011b). The current work shows that these performance regime boundaries are affected by rotational speed and intake-stage pressure.