INTERFACE:
subroutine lengthscaleeq(nlev,dt,depth,u_taus,u_taub,z0s,z0b,h,NN,SS)DESCRIPTION:
Following suggestions of Rotta (1951), Mellor and Yamada (1982) proposed an equation for the product expressed by
The so-called wall function, , appearing in (162) is defined by
For horizontally homogeneous flows, the transport term appearing in (162) is expressed by a simple gradient formulation,
At the end of this routine the length-scale can be constrained according to a suggestion of Galperin et al. (1988). This feature is optional and can be activated by setting length_lim = .true. in gotmturb.nml.
USES:
use turbulence, only: P,B use turbulence, only: tke,tkeo,k_min,eps,eps_min,L use turbulence, only: kappa,e1,e2,e3,b1 use turbulence, only: MY_length,cm0,cde,galp,length_lim use turbulence, only: q2l_bc, psi_ubc, psi_lbc, ubc_type, lbc_type use turbulence, only: sl use util, only: Dirichlet,Neumann IMPLICIT NONEINPUT PARAMETERS:
number of vertical layers integer, intent(in) :: nlev time step (s) REALTYPE, intent(in) :: dt local water depth (m) REALTYPE, intent(in) :: depth 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 (re-write after first version of H. Burchard and K. Bolding
Karsten Bolding 2012-12-28