Numerical simulation of pump-intake vortices

Influence of Rotational Wall of Axial Inlet Device on Velocity Distribution at Impeller Inlet

“…At the outlet of the diffuser section, fluid is swirled by the impeller and circumferential component of absolute velocity increases similar to the situation described in [6,11]. Moreover, the uneven distribution of the absolute velocity vectors increases.…”

“…More often, for determining the theoretical head Euler equation is used [1], which directly takes into account the influence of circumferential component of absolute velocity on the pump head. In general, the average value of the velocities or their components in the cross section is used to simplify the theoretical and practical calculations [6]. This makes a constant error in calculation results.…”

“…Song et al [5] discovered that flat inlet elbow forms a less circumferential component of absolute velocity of a flow compared to asymmetric inlet casing and the large radius elbow. Rudolf and Klas [6] studied a vortex flow structure at the inlet of the vertical submersible pump, which pumped fluid from open water, and found that the uneven absolute velocity distribution increases with rise of the flow rate.…”

Application of Polyhedral Mesh for Vortex Formation Study for Simple Single Pump Sump

“…This was made on the basis that the generated vortices are not strong enough to produce a vortex core filled with air, which is the vortex strength of lower than Type 4 as per ANSI/HI 9.8 [29]. This was practiced by past research which stated that several authors proved that while omitting phase interface at the water surface did not prevent the capturing of the vortices, adopting this would extremely reduce the computational time and complexity of the simulation [30]. The simulation employed SST 𝑘 − 𝜔 model since it was found to be a better turbulence model in modelling vortex formation in pump sump compared to the 𝑘 − ε models such as standard, Realizable and RNG 𝑘 − ε models, with respect to the treatment at the near wall without refining the mesh sizes [17].…”