Detached Eddy Simulation Model to Evaluate Design of Pump Stations

Detached eddy simulations with a deformable free-surface are used to predict flow and vortical structure in a pump station and to determine the severity of adverse hydraulic conditions inside the pump bays and pump columns. The model includes the approach channel to the five pump bays. Two of the bays contain vertical pump columns with a suction bell. The other bays contain a draft-tube-like structure (formed suction inlet) leading to a vertical pump column. The simulations are conducted at lab scale using 1:10 geometrical scaling and Froude number similarity. To mimic different operating scenarios, simulations are conducted with all five pumps operating and with only three pumps operating. Additionally, one simulation is conducted with several flow training devices present. Simulations accurately predict the type of vortices forming inside the pump bays, the level of flow nonuniformity inside the pump columns and the swirl angle at the level of the pump impeller. This study demonstrates the feasibility of using eddy-resolving simulations as a tool to evaluate and improve design of new and existing pump stations.