CMS-Flow:Subgrid Turbulence Model

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Eddy Viscosity

In CMS-Flow eddy viscosity is calculated as the sum of the kinematic viscosity , the current-related eddy viscosity and the wave-related eddy viscosity

     

There are two options to calculate . The first is the Falconer (1980) equation given by


     


where is the bottom friction coefficient, is the depth-averaged current velocity, and is the total water depth.

The second option is a subgrid turbulence model given by

     

where is an empirical coefficient approximately equal to 1/6, is an empirical coefficient between 0.25-0.5, and math>\Delta y</math> are the grid dimensions in the x and y directions and Normal 0 false false false MicrosoftInternetExplorer4 is equal to

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The wave component of the eddy viscosity is calculated as

     

where is an empirical coefficient, is the water density, and is the total wave dissipation.




CMS-Flow