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Background
Multistage centrifugal pumps with diffuser vanes are used in
the oil industry to pump produced water, i.e. water which is
separated from the oil. The produced water contains salt water
with small oil droplets. Because of environmental regulations,
the oil droplets need to be separated from the produced water
before the water is released back into the sea. The efficiency
of the separation process is dependent on the size of the oil
droplets. It is therefore desired to obtain the optimal size.
The pumps that are used today has a tendency of making
the droplets smaller. A company in Stavanger, Norway named
Typhonix is researching on a multistage centrifugal pump
which under certain operating conditions is able to enlarge the
oil droplets. The increase in droplet size increases the energy
efficiency of the separation process compared to the traditional
pumps.
This thesis is a continuation of the work done in my project
thesis. A test rig for the centrifugal pump has been built in the
Waterpower laboratory. The flow characteristics in the diffuser
of the pump will be investigated further and more thoroughly,
providing PhD. candidate Alessandro Nocente with experimental
data. The equipment used for measuring the velocity is Laser
Doppler Velocimetry (LDV). This data will be compared with a CFD
simulation performed in Fluent to possibly verify the numerical
model.
In addition a mesh sensitivity analysis of the numerical model
will be performed. The mesh will be modified by using Ansys
ICEM. Also, the solution from Fluent will be compared with a
OpenFOAM solution.
Supervisor: Torbjørn K. Nielsen
Co-supervisor: Alessandro Nocente
By Karl Oskar Pires Bjørgen
Master Thesis
Waterpower Laboratory
LDV Measurements in
Centrifugal Pump Diffuser
The diffuser of the test rig
Velocity field of the diffuser,
results from the project thesis