3D-CFD simulation of a vortex dropshaft with an upstream stabilization basin

Mattias Deller, June 15, 2021

Hydraulic capacity validation of a vortex dropshaft with a fall height of 68 m using 3D-CFD simulations

Water level in the vortex dropshaft at the end of the calculation, the flow velocities are shown

The rainwater is currently evacuated into the receiving water via a vortex dropshaft with a maximum capacity of 4 m3/s and a downpipe length of 68 m. The general drainage plan shows that the maximum capacity of the existing vortex dropshaft is not sufficient. For this reason a vortex dropshaft with an increased capacity of 12.6 m3/s, has to be built. A stabilization chamber is located in front of the planned new vortex dropshaft. The existing vortex dropshaft is also connected to the stabilization chamber and it can be used in the case of maintenance work on the new vortex dropshaft. Using a two-phase 3D-CFD simulation (water/air), the hydraulically critical areas (inflows into the stabilization chamber, firing ramp to the vortex dropshaft, ventilation performance, functionality of the dissipation chamber) âre in detail investigated and iteratively optimized in accordance with the planner.

Stationary inflow of 12.6 m3/s