FORMATION MECHANISM OF AN ADHERENT VORTEX IN THE SIDE PUMP SUMP OF A PUMPING STATION

The inflow of the side pump sump is not smooth enough during the operation of a pumping station, resulting in an asymmetric adherent vortex that endangers the station's normal operation and safety. To solve this problem, flow field and vorticity distribution charts of different flow layers were created through the establishment of a numerical model of the pumping station inflow by means of the fluid simulation software. The formation mechanism of the asymmetric adherent vortex in the side pump sump was analysed by combining Reynolds shear stress distribution, the simplified Navier-Stokes equation, and the transport equation of turbulent kinetic energy. Furthermore, the accuracy of the numerical simulation results was verified using flow field data collected via particle image velocimetry at the junction of the forebay and pump sumps of the station. Results show that the distribution of inflow velocity is uneven due to the asymmetric friction of the inflow in the side pump sump. The transverse velocity formed from it generates the asymmetric vortex in the side pump sump and creates an inspiratory vortex.