At the Tianshan first-grade pumping station,water level of the forebay and suction sump is controlled by a sluice at the forebay inlet.To improve flow patterns formed by the jet under the sluice,the RANS equations and a standard k-e turbulence model are used to simulate the flow and to study different schemes.Simulation results show that the most effective scheme is the one combining three engineering measures,non-continuous bottom sills,non-continuous trajectory sills and pressurized water plate.In this scheme,the overall flow in the forebay and suction sump is improved with smaller velocities near the bottom and around the pump inlet.Sediment accumulations in the forebay and behind the bottom sills and trajectory sills are avoided or decreased.Field test showed that since the proposed schemes were adopted,pumping station vibrations have been reduced obviously,operating efficiency of the pump increased,and sediment accumulation decreased.These results provide important data for renovation of foreby and suction sump of the pumping stations on Yellow River.

According to the jet feature under the sluice that formed by the water level difference in Tianshan first-stage pumping station, the efforts of fluid meliorating were put forward. The RANS equation and standard k-ε turbulence model were used to simulate the flow state, and the influence of sediment on the water flow was not taken into consideration during the simulating process. Due to the attempts of adopting discontinuous bottom sills, discontinuous trajectory sills and pressurized water board, the results show that the jet length is shorten significantly, the surface backflow disappears, the cross-section velocity distribution tends to uniform, and the velocity at the bottom of the forebay and suction bay and near the pump inlet decreases significantly. The field investigations show that the modifications adopted increase the device efficiency by 1.82% and 5.96% respectively. The vibration amplitude decreases 21 μm and 52 μm, and the sediment accumulation almost disappears in both operating conditions.