Interaction of a pulsating vortex rope with the local velocity field in a Francis turbine draft tube

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The flow in a Francis turbine at full load is characterised by the development of an axial vortex rope in the draft tube. The vortex rope often promotes cavitation if the turbine is operated at a sufficiently low Thoma number. Furthermore, the vortex rope ...

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Interaction of a pulsating vortex rope with the local velocity field in a Francis turbine draft tube

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