INTERFACE:
REALTYPE function epsilon_bc(bc,type,zi,ki,z0,u_tau)DESCRIPTION:
Computes prescribed and flux boundary conditions for the transport equation (165). The formal parameter bc determines whether Dirchlet or Neumann-type boundary conditions are computed. Depending on the physical properties of the boundary-layer, the parameter type relates either to a visous, a logarithmic, or an injection-type boundary-layer. In the latter case, the flux of TKE caused by breaking surface waves has to be specified. Presently, there is only one possibility to do so implemented in GOTM. It is described in section 4.34. All parameters that determine the boundary layer have to be set in gotmturb.nml.
Note that in this section, for brevity, denotes the distance from the wall (or the surface), and not the standard coordinate of the same name used in GOTM.
Viscous boundary-layers
This type is not implemented yet in GOTM.
Logarithmic boundary-layers
The Dirichlet (prescribed) boundary condition follows from (155) as
The Neumann (flux) boundary condition can be expressed as
Shear-free boundary-layers with injection of TKE
The Dirichlet (prescribed) boundary condition follows simply from the power-law (110) inserted in (155). This yields
The Neumann (flux) boundary condition is
USES:
IMPLICIT NONEINPUT PARAMETERS:
integer, intent(in) :: bc,type REALTYPE, intent(in) :: zi,ki,z0,u_tauREVISION HISTORY:
Original author(s): Lars Umlauf
Karsten Bolding 2012-12-28