INTERFACE:
subroutine tkeeq(nlev,dt,u_taus,u_taub,z0s,z0b,h,NN,SS)DESCRIPTION:
The transport equation for the turbulent kinetic energy, , follows immediately from the contraction of the Reynolds-stress tensor. In the case of a Boussinesq-fluid, this equation can be written as
In horizontally homogeneous flows, the shear and the buoyancy production, and , can be written as
The rate of dissipation, , can be either obtained directly from its parameterised transport equation as discussed in section 4.15, or from any other model yielding an appropriate description of the dissipative length-scale, . Then, follows from the well-known cascading relation of turbulence,
USES:
use turbulence, only: P,B,num use turbulence, only: tke,tkeo,k_min,eps use turbulence, only: k_bc, k_ubc, k_lbc, ubc_type, lbc_type use turbulence, only: sig_k 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 (re-write after first version of H. Burchard and K. Bolding)
Karsten Bolding 2012-12-28