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Subsections


cbfset.F


subroutine cbfset

Description

Calculates the bottom drag coefficient assuming a logarithmic boundary layer.

Numerical Equations


\begin{displaymath}
C_d = \left( {{\frac{{\kappa}} {{\ln (z / z_{0}}} }} \right)^{2}
\end{displaymath}

Where C_d is the bottom drag coefficient, $\kappa$ is the Von Karman constant $z\_0$ is the bed roughness length and $z$ is the hight above the bed. If $C_d$ is less than 0.005, $C_d$ is assumed to be 0.005

Subroutine Arguments

none

Local variables

vkappa Von Karman constant.
z0 Bed roughness.
i,j Grid indeces.

Global variables changed

cdb

Logical units

none

Order of Things

  1. Sets the Von Karman constant and roughness values.
  2. Calculates the drag coefficient.
  3. Sets the drag coefficient to be 0.005 or larger.

Calls

none

Called By

b3dinit, barot

Options - Logical

none

Options - Compiler

MY25CBF
SCOORD
COASTFRIC An experimental option to increase friction near coasts - can be unstable.

Known Issues


next up previous
Next: chkpnt.F Up: The Proudman Oceanographic Laboratory Previous: bset.F
The AMMP Project 2005-04-20