Numerical simulation of rectification and vortex suppression in the inlet sump of a pumping station

Abstract In response to flow irregularities observed within the inlet sump of a pumping station in Taiwan, this study undertook structural optimization of the inlet sump utilizing numerical simulation techniques based on the Reynolds time-averaged Navier-Stokes (N-S) equations and RNG k-ε turbulence model. A comparative examination of the internal flow characteristics of the inlet sump before and after optimization at the designated flow rate was conducted. The findings revealed that prior to optimization, backflow was evident within the inlet sump under the operational conditions of the four units, coupled with the presence of vortices beneath the intake bell mouth of the pumps, resulting in suboptimal intake conditions. Optimization strategies involved the installation of guide walls between the units, adjustment of the back wall shape, and addition of guide cones beneath the intake bell mouth of the pumps. Results indicated that the guide walls effectively redirected flow, encouraging it to follow along the guide walls, thereby enhancing the flow pattern within the inlet sump. Additionally, the guide cones successfully mitigated the formation of vortices beneath the bell mouth, consequently improving the intake conditions for the pumps.