PLT - Closing the Gap: Combining numerical and analytical methods to predict gate closures

Gates play a critical role in the operation and maintenance of Hydropower facilities. A recent potential failure mode analysis identified runaway turbine operation as a credible potential failure mode. Therefore, demonstrating adequate gate closure during this potential failure is critical to the turbine shutdown process. Seating the gate requires the overcoming multiple forces, which may vary by orders of magnitude during the closure. Analytical methods and Computational Fluid Dynamics (CFD) were combined to determine the forces the gates and crane system would experience during a potential runaway turbine failure mode. The CFD model supplied the hydrodynamic forces the system would need to overcome during closure and the analytical methods showed the potential failure points of the gates. A repeatable analysis process was developed using previous physical and numerical models allowing the multiple unique turbine and intake configurations to be evaluated. The portfolio analysis allowed the utility to take a systems approach, understand various risk scenarios, and prioritize actions to address the areas of highest risk.