泵站拦污栅淤堵对进水流道内水流流动特性的影响OA

To investigate the influence of trash rack clogging on the internal flow characteristics within the inlet passage of a pumping station,a CFD numerical simulation method was conducted based on the RNG κ-ε turbulence model to analyze the water flow within the inlet passage of an axial-flow pump.The flow pattern,pressure distribution,vortex distribution,turbulent kinetic energy,and flow velocity uniformity of the vertical axial-flow pump unit at the inlet cross-section were studied under four diffe-rent clogging schemes.The results show that trash rack clogging leads to a severely uneven velocity dis-tribution at the inlet passage entrance:a low-velocity region forms in the clogged area,while high-velocity regions appear in the surrounding unclogged areas.The maximum flow velocity increases from 1.38 m/s under the unclogged condition of Scheme 1 to 1.89 m/s under Scheme 4.Clogging also cau-ses a significant reduction in the cross-sectional water pressure.Due to the clogging,the flow pattern becomes turbulent,generating complex vortex structures mainly concentrated in the clogged areas,and the number of vortices increases with the clogged area.As the clogging amount increases,the turbulent kinetic energy increases,and the flow velocity uniformity decreases from 56％under the unclogged condition to a minimum of 45％,representing a reduction of 11 percentage points.The research results can provide a theoretical basis for the design,operation,and maintenance of trash racks in pumping stations,and have certain academic value and theoretical significance.