Difference between revisions of "Numerical Solution Technique"

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<div class="title">Numerical Solution Technique</div>
<div class="title">Numerical Solution Technique</div>


==Vertical and Horizontal Discretization==
==Horizontal and Vertical Discretization==
 
The ROMS governing equations are discretized over variable topography using a stretched, terrain-following, vertical coordinate.  As a result, each grid cell may have different level thickness (Hz) and volume. The model state variables are vertically staggered so that horizontal momentum (u,v), density, and tracers (active and passive) are located at the center of the grid cell. The vertical velocity (&omega;, w) and vertical mixing variables (Akt, Akv, etc) are located at the bottom and top faces of cell. See diagram below.
 
[[Image:vertical_grid.png|ROMS vertical grid]]


[[Image:staggered_grid_rho_cells.png|ROMS staggered rho grid]]
[[Image:staggered_grid_rho_cells.png|ROMS staggered rho grid]]


The ROMS governing equations are discretized over variable topography using a stretched, terrain-following, vertical coordinate.  As a result, each grid cell may have different level thickness (Hz) and volume. The model state variables are vertically staggered so that horizontal momentum (u,v), density, and tracers (active and passive) are located at the center of the grid cell. The vertical velocity (&omega;, w) and vertical mixing variables (Akt, Akv, etc) are located at the bottom and top faces of cell. See diagram below.


[[Image:staggered_grid_u_cells.png|ROMS staggered u grid]]
[[Image:vieste-dubrovnik.png|left|frame|<center>Vieste-Dubrovnik Transect</center>]]
 
[[Image:vertical_grid.png|none|frame|<center>ROMS vertical grid</center>]]
 
<div style="clear:both;"></div>
[[Image:staggered_grid_v_cells.png|ROMS staggered v grid]]


==Time-Stepping==
==Time-Stepping==

Revision as of 13:28, 7 March 2008

Numerical Solution Technique

Horizontal and Vertical Discretization

ROMS staggered rho grid

The ROMS governing equations are discretized over variable topography using a stretched, terrain-following, vertical coordinate. As a result, each grid cell may have different level thickness (Hz) and volume. The model state variables are vertically staggered so that horizontal momentum (u,v), density, and tracers (active and passive) are located at the center of the grid cell. The vertical velocity (ω, w) and vertical mixing variables (Akt, Akv, etc) are located at the bottom and top faces of cell. See diagram below.

Vieste-Dubrovnik Transect
ROMS vertical grid

Time-Stepping

Horizontal and Vertical Advection

Pressure Gradient