Turbine hydraulic assessment and optimization in rehabilitation projects

As turbines age after years of operation, a major rehabilitation is needed to give new life. The owner has two choices: resetting the turbine to the original state or an upgrade with new hydraulic components designed and optimized using state of the art technology. The second solution is by far a more interesting option which can maximize the efficiency gain, increase the turbine capacity and revenues, eliminate cavitation erosion and the needs for repair, reduce the turbine instabilities and smooth unit regulation, and adapt the design to new operation conditions. This paper shows some aspects of the turbine hydraulic assessment and possible solutions to improve existing water passages.