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This picture shows a cavitated whip
at part load in the draft tube of a
francis runner. Which will cause
pressure pulsations.
This picture show two Pitot tubes used measure the volume
flow at Øvre Leirfoss Power Plant.
Background
The purpose of the this thesis will be to perform both efficiency measurements and
measurements of pressure pulsations in three low head power plants in Nidelva. These three
are; Øvre Leirfossen, Nedre Leirfossen and Leirfossene Power Plant.
The efficiency measurements at Øvre and Nedre Leirfoss will be done with Pitot, while the
efficiency measurements at Leirfossene will be done with both Gibson’s method and with
thermodynamic method. These methods will then be compared with each other and similar
measurements at other power plants.
The pressure pulsations will be measured in the draft tubes of all three power plants.
Supervisor: Ole G. Dahlhaug
By Anders Jensen Aas
Master Thesis
Waterpower Laboratory
Efficiency and Pressure
Pulsation Measurements at
Low Head Hydropower Plants