Subsurface Vortex Control Parametric Study at Submersible Pump Intake Using Plate-Type Floor Splitters

Abstract

Vortex formation near the pump inlet in the sump during intake is a phenomenon that needs to be controlled to maximize the pump efficiency. In this study, five variants of an AVD type called the plate type floor splitter are installed in a single intake pump sump model to evaluate the effect of geometry of the floor splitter on the effectiveness of vortex control in the intake flow. The acceptance criteria according to ANSI HI 9.8 2012 standard are that the vortex formed in the sump must be eliminated and the swirl angle in the flow must not exceed 5°. The submergence of the inlet was varied to observe the swirl reduction effect at different water levels. All floor splitter variants employed in this study have successfully eliminated the vortex but most of them did not manage to reduce the swirl angle below 5° as required. The variants with different heights displayed significant differences in swirl angle values with higher variants produce greater swirl angle reduction. The highest floor splitter variant managed to produce a swirl angle reduction below 5°. With varying lengths, however, the swirl angle values did not differ much in each case with the installation of the floor splitter variants. The advantage of the long floor splitter is that the fluctuation of swirl angle values is minimum for all submergence depths greater than 0.9 times the minimum inlet submergence which implies that the swirl reduction effect is less affected by the change in water level. By combining the advantages of both floor splitter design variation, the optimal design of plate type floor splitter can be achieved.