Numerical and experimental investigation of the unsteady flow field over a simplified hydrofoil plate

Abstract

In this thesis, the behavior of a simplified hydrofoil in an unsteady water flow field is tested. Due to frequent load variations in high head Francis turbines, the runner vanes happen to break. Rotor stator interaction causes vibrations on the runner vanes. To simulate those vibrations in laboratory conditions, the hydrofoil, mounted in a cascade test rig, is excited with piezo electric patches. The experiment in this thesis shows the behavior of the hydrofoil in different water flow velocities. The results are analyzed and conclusions are brought.