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Department of Energy and
Process Engineering
Fall 2016
Development of the
Pressure-Time as a
Relative Method
Supervisor:
Michel Cervantes
Helene Njølstad Dagsvik
Background and objective
Hydraulic efficiency testing is an essential tool
to investigate the performance of hydraulic
turbines and pumps. The Winther-Kennedy
method is a relative efficiency method and is
usually preferred when testing the efficiency
of low-head turbomachines. This method has
shown some inconsistency over time and an
alternative method is desired. The pressure-
time (Gibson) method may be evaluated as a
relative method by using the upper reservoir as
one of two measuring sections. This method is
simple and cheap to install and could be the
alternative.
The objective of this master thesis is to do
a relative evaluation of the pressure-time
measurements previously performed in the
Gibson test rig at the Water Power Laboratory.
The relative results will be compared to a
numerical MOC code written to simulate the
experimental results.
MASTER THESIS
This illustration shows the
principle behind relative
pressure-time measurements.
The atmospheric pressure
and a pressure upstream
the hydraulic gate is used to
calculate the relative, unsteady
Gibson flow