Consultants at CFD-RES used FLUENT to model the flow through a wastewater pump-station for the Woodman Alliance. Flow falls from a pipe into a distribution chamber and then moves through penstocks (rectangular gaps in the dividing walls) into three wet wells. From these wet wells the flow is pumped out through pipes for treatment downstream. A key design issue is the prevention of a vortex forming around the mouth of the exit pipes that can lead to the entrainment of air into the pumps. The vortex that forms is caused by swirling motion and is a function of the penstock location within the dividing walls. The CFD analysis helped determine the appropriate penstock locations to minimize swirling and thus, the likelihood of vortex formation.

Velocity magnitude contours at three vertical slices through the centers of the exit pipes/pumps
Courtesy of WA21 The Woodman Alliance