INTERFACE:
subroutine genericeq(nlev,dt,u_taus,u_taub,z0s,z0b,h,NN,SS)DESCRIPTION:
This model has been formulated by Umlauf and Burchard (2003), who introduced a `generic' variable,

The transport equation for can written as
For horizontally homogeneous flows, the transport terms appearing in (166) are expressed by a simple gradient formulation,
For appropriate choices of the parameters, most of the classic transport equations can be directly recovered from the generic equation (166). An example is the transport equation for the inverse turbulent time scale, , which has been formulated by Wilcox (1988) and extended to buoyancy affected flows by Umlauf et al. (2003). The precise definition of follows from table 8, and its transport equation can be written as

USES:
use turbulence, only: P,B,num use turbulence, only: tke,tkeo,k_min,eps,eps_min,L use turbulence, only: cpsi1,cpsi2,cpsi3plus,cpsi3minus,sig_psi use turbulence, only: gen_m,gen_n,gen_p use turbulence, only: cm0,cde,galp,length_lim use turbulence, only: psi_bc, psi_ubc, psi_lbc, ubc_type, lbc_type use util, only: Dirichlet,Neumann IMPLICIT NONEINPUT PARAMETERS:
number of vertical layers integer, intent(in) :: nlev time step (s) REALTYPE, intent(in) :: dt surface and bottom friction velocity (m/s) REALTYPE, intent(in) :: u_taus,u_taub surface and bottom roughness length (m) REALTYPE, intent(in) :: z0s,z0b layer thickness (m) REALTYPE, intent(in) :: h(0:nlev) square of shear and buoyancy frequency (1/s^2) REALTYPE, intent(in) :: NN(0:nlev),SS(0:nlev)REVISION HISTORY:
Original author(s): Lars Umlauf and Hans Burchard $Log: genericeq.F90,v $ Revision 1.9 20051228 08:51:10 hb Bug fix: Now tkeo is used for reconstruction of psi Revision 1.8 20051115 11:35:02 lars documentation finish for print Revision 1.7 2005/11/03 20:53:37 hb Patankar trick reverted to older versions for stabilising 3D computations Revision 1.6 2005/08/11 13:11:50 lars Added explicit loops for diffusivities for 3D zlevel support. Thanks to Vicente Fernandez. Revision 1.5 2005/06/27 13:44:07 kbk modified + removed traling blanks Revision 1.4 2003/03/28 09:20:35 kbk added new copyright to files Revision 1.3 2003/03/10 09:02:05 gotm Added new Generic Turbulence Model + improved documentation and cleaned up code
Karsten Bolding 20120124