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PHD THESIS
Background
Today, Francis runners are designed and
verified by means of numerical methods. The
challenge is to get reliable results for pressure
oscillations in the fluid and the natural frequency
of the runner. To be able to verify and improve
calculated and simulated values, experiments
must be performed.
Objective and method
The objective of this thesis is to investigate the
fluid structure interaction in a Francis turbine
runner. To get a better understanding of the
physics, measurements will be performed to
find the fluid influence on the runner, and the
runners response to this influence. Quantities
measured include pressure and velocity of the
fluid, and acceleration, strain and displacement
of the runner. The measurements will be
compared with numerical results.
In addition, the relation between a stiff and
a softer runner will be investigated to see
the effect of runner movement closer to the
resonance condition.
Department of Energy
and Process Engineering
2016-2019
High head Francis
Turbines
Supervisor:
Ole Gunnar Dahlhaug
Einar Agnalt
Pressure sensors in the hub of Francis99 model runner
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