General
RMA-10 is a three-dimensional
finite element model for stratified flow (King [1993]). The primary features of RMA-10 are:
·
the solution of the shallow water equations in
three-dimensions with hydrostatic assumptions;
·
coupling of advection and diffusion of temperature,
salinity and sediment to the hydrodynamics;
·
the inclusion of turbulence in Reynolds stress form;
·
horizontal components of the non-linear terms are
included;
·
a capacity to include one-dimensional, depth-averaged,
laterally-averaged two dimensional elements and three-dimensional elements
within a single mesh as needed;
·
no, partial and full slip conditions can be applied at
lateral boundaries and bed boundaries;
·
all elements can be made to wet and dry during a
simulation;
·
vertical turbulence quantities are estimated by either
a quadratic parameterisation of turbulent exchange or a Mellor-Yamada Level 2
turbulence sub-model;
·
binary output of 3D geometry, results and restart
files to minimise disk usage;
·
it has had extensive
use in computing coastal and estuarine flows (particularly San Francisco Bay
(US), Galveston Bay (US), Sydney coastal
waters (Aust.) and Illawarra (Aust.) ).
The finite element formulation
of RMA-10 is particularly useful in refining detailed flow features like the
Urmston Road passage and North Western Waters of Hong Kong. By having the ability to shoreline fit
finite elements around irregular coastlines and to have much finer mesh resolution
in regions of interest and rapidly varying flows, RMA-10 can avoid many problems involved with
discretising a solution into a regular grid spacing.
Recent work in the Sydney
coastal waters (Wilson et al [1994]) has shown the capability of modelling
temperature stratified flow with varying velocity gradients in open coastal
waters.