2D Modelling of turbulant transport of cohesive sediments in shallow reservoirs
Date
2006-12
Authors
De Villiers, J. W. L.
Journal Title
Journal ISSN
Volume Title
Publisher
Stellenbosch : University of Stellenbosch
Abstract
Modelling of the transport of fine cohesive sediments, as found in most South African
reservoirs, has not been well developed. This is because the transport processes that are
involved are complex and the theories not as implicit as the traditional equilibrium
transport theories for coarse non-cohesive sediment. Advection and dispersion are found to
be the processes that best describe the transport of fine sediments in turbulent flow
conditions.
A two-dimensional modelling tool, MIKE 21C, which simulates reservoir hydrodynamics
and cohesive sediment transport processes with an advection-dispersion model, was
evaluated in this thesis. The creation of such a numerical model involves the setting up of
a suitable curvilinear grid and requires data on the bathymetry, recorded inflows as well as
water levels. It also requires sediment characteristic parameters and transport parameters.
These parameters have to be specified by the user based on previous studies and field
measurement data.
MIKE 21C was applied to laboratory flume tests and reservoir case studies in the field in
order to determine the effects that these parameters have on the sediment transport in a
series of sensitivity studies. Ranges were determined within which these parameter values
should fall. A procedure was also developed through which reservoir sedimentation
models can be calibrated.
Description
Thesis (MScEng (Civil Engineering))--University of Stellenbosch, 2006.
Keywords
Reservoir sedimentation, Sediment transport, Theses -- Civil engineering, Dissertations -- Civil engineering