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C $Header: /u/gcmpack/MITgcm/pkg/mom_vecinv/mom_vi_hdissip.F,v 1.5 2004/02/07 23:15:47 dimitri Exp $ |
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C $Name: $ |
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|
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#include "CPP_OPTIONS.h" |
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|
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SUBROUTINE MOM_VI_HDISSIP( |
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I bi,bj,k, |
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I hDiv,vort3,hFacZ,dStar,zStar, |
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c I viscAh_Z,viscAh_D,viscA4_Z,viscA4_D, |
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O uDissip,vDissip, |
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I myThid) |
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IMPLICIT NONE |
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C |
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C Calculate horizontal dissipation terms |
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C [del^2 - del^4] (u,v) |
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C |
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|
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C == Global variables == |
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#include "SIZE.h" |
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#include "GRID.h" |
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#include "EEPARAMS.h" |
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#include "PARAMS.h" |
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|
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C == Routine arguments == |
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INTEGER bi,bj,k |
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_RL hDiv(1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL vort3(1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RS hFacZ(1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL dStar(1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL zStar(1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL viscAh_Z(1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL viscAh_D(1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL viscA4_Z(1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL viscA4_D(1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL uDissip(1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL vDissip(1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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INTEGER myThid |
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|
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C == Local variables == |
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INTEGER I,J |
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_RL Zip,Zij,Zpj,Dim,Dij,Dmj,uD2,vD2,uD4,vD4 |
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_RL Alin,Alth,grdVrt,vg2,vg4 |
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LOGICAL useVariableViscosity |
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|
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useVariableViscosity= |
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& (viscAhGrid*deltaTmom.NE.0.) |
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& .OR.(viscA4Grid*deltaTmom.NE.0.) |
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& .OR.(viscC2leith.NE.0.) |
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& .OR.(viscC4leith.NE.0.) |
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|
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IF (deltaTmom.NE.0.) THEN |
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vg2=viscAhGrid/deltaTmom |
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vg4=viscA4Grid/deltaTmom |
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ELSE |
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vg2=0. |
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vg4=0. |
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ENDIF |
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|
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C - Viscosity |
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IF (useVariableViscosity) THEN |
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DO j=2-Oly,sNy+Oly-1 |
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DO i=2-Olx,sNx+Olx-1 |
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C This is the vector magnitude of the vorticity gradient |
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c grdVrt=sqrt(0.25*( |
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c & ((vort3(i+1,j)-vort3(i,j))*recip_DXG(i,j,bi,bj))**2 |
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c & +((vort3(i,j+1)-vort3(i,j))*recip_DYG(i,j,bi,bj))**2 |
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c & +((vort3(i+1,j+1)-vort3(i,j+1))*recip_DXG(i,j+1,bi,bj))**2 |
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c & +((vort3(i+1,j+1)-vort3(i+1,j))*recip_DYG(i+1,j,bi,bj))**2 )) |
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C but this approximation will work on cube (and differs by as much as 4X) |
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grdVrt=abs((vort3(i+1,j)-vort3(i,j))*recip_DXG(i,j,bi,bj)) |
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grdVrt=max(grdVrt, |
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& abs((vort3(i,j+1)-vort3(i,j))*recip_DYG(i,j,bi,bj))) |
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grdVrt=max(grdVrt, |
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& abs((vort3(i+1,j+1)-vort3(i,j+1))*recip_DXG(i,j+1,bi,bj))) |
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grdVrt=max(grdVrt, |
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& abs((vort3(i+1,j+1)-vort3(i+1,j))*recip_DYG(i+1,j,bi,bj))) |
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Alth=viscC2leith*grdVrt*(rA(i,j,bi,bj)**1.5) |
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Alin=viscAh+vg2*rA ( i , j ,bi,bj) |
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viscAh_D(i,j)=min(viscAhMax,Alin+Alth) |
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|
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Alth=viscC4leith*grdVrt*0.125*(rA(i,j,bi,bj)**2.5) |
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Alin=viscA4+vg4*(rA ( i , j ,bi,bj)**2) |
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viscA4_D(i,j)=min(viscA4Max,Alin+Alth) |
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|
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C This is the vector magnitude of the vorticity gradient |
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c grdVrt=sqrt(0.25*( |
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c & ((vort3(i+1,j)-vort3(i,j))*recip_DXG(i,j,bi,bj))**2 |
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c & +((vort3(i,j+1)-vort3(i,j))*recip_DYG(i,j,bi,bj))**2 |
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c & +((vort3(i-1,j)-vort3(i,j))*recip_DXG(i-1,j,bi,bj))**2 |
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c & +((vort3(i,j-1)-vort3(i,j))*recip_DYG(i,j-1,bi,bj))**2 )) |
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C but this approximation will work on cube (and differs by as much as 4X) |
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grdVrt=abs((vort3(i+1,j)-vort3(i,j))*recip_DXG(i,j,bi,bj)) |
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grdVrt=max(grdVrt, |
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& abs((vort3(i,j+1)-vort3(i,j))*recip_DYG(i,j,bi,bj))) |
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grdVrt=max(grdVrt, |
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& abs((vort3(i-1,j)-vort3(i,j))*recip_DXG(i-1,j,bi,bj))) |
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grdVrt=max(grdVrt, |
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& abs((vort3(i,j-1)-vort3(i,j))*recip_DYG(i,j-1,bi,bj))) |
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Alth=viscC2leith*grdVrt*(rAz(i,j,bi,bj)**1.5) |
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Alin=viscAh+vg2*rAz( i , j ,bi,bj) |
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viscAh_Z(i,j)=min(viscAhMax,Alin+Alth) |
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|
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Alth=viscC4leith*grdVrt*0.125*(rAz(i,j,bi,bj)**2.5) |
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Alin=viscA4+vg4*(rAz( i , j ,bi,bj)**2) |
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viscA4_Z(i,j)=min(viscA4Max,Alin+Alth) |
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ENDDO |
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ENDDO |
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ELSE |
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DO j=1-Oly,sNy+Oly |
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DO i=1-Olx,sNx+Olx |
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viscAh_D(i,j)=viscAh |
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viscAh_Z(i,j)=viscAh |
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viscA4_D(i,j)=viscA4 |
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viscA4_Z(i,j)=viscA4 |
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ENDDO |
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ENDDO |
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ENDIF |
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|
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C - Laplacian and bi-harmonic terms |
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DO j=2-Oly,sNy+Oly-1 |
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DO i=2-Olx,sNx+Olx-1 |
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|
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Dim=hDiv( i ,j-1) |
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Dij=hDiv( i , j ) |
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Dmj=hDiv(i-1, j ) |
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Zip=hFacZ( i ,j+1)*vort3( i ,j+1) |
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Zij=hFacZ( i , j )*vort3( i , j ) |
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Zpj=hFacZ(i+1, j )*vort3(i+1, j ) |
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|
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C This bit scales the harmonic dissipation operator to be proportional |
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C to the grid-cell area over the time-step. viscAh is then non-dimensional |
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C and should be less than 1/8, for example viscAh=0.01 |
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if (useVariableViscosity) then |
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Dij=Dij*viscAh_D(i,j) |
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Dim=Dim*viscAh_D(i,j-1) |
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Dmj=Dmj*viscAh_D(i-1,j) |
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Zij=Zij*viscAh_Z(i,j) |
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Zip=Zip*viscAh_Z(i,j+1) |
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Zpj=Zpj*viscAh_Z(i+1,j) |
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uD2 = ( |
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& cosFacU(j,bi,bj)*( Dij-Dmj )*recip_DXC(i,j,bi,bj) |
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& -recip_hFacW(i,j,k,bi,bj)*( Zip-Zij )*recip_DYG(i,j,bi,bj) ) |
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vD2 = ( |
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& recip_hFacS(i,j,k,bi,bj)*( Zpj-Zij )*recip_DXG(i,j,bi,bj) |
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& *cosFacV(j,bi,bj) |
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& +( Dij-Dim )*recip_DYC(i,j,bi,bj) ) |
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else |
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uD2 = viscAh*( |
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& cosFacU(j,bi,bj)*( Dij-Dmj )*recip_DXC(i,j,bi,bj) |
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& -recip_hFacW(i,j,k,bi,bj)*( Zip-Zij )*recip_DYG(i,j,bi,bj) ) |
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vD2 = viscAh*( |
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& recip_hFacS(i,j,k,bi,bj)*( Zpj-Zij )*recip_DXG(i,j,bi,bj) |
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& *cosFacV(j,bi,bj) |
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& +( Dij-Dim )*recip_DYC(i,j,bi,bj) ) |
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endif |
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|
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Dim=dyF( i ,j-1,bi,bj)*dStar( i ,j-1) |
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Dij=dyF( i , j ,bi,bj)*dStar( i , j ) |
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Dmj=dyF(i-1, j ,bi,bj)*dStar(i-1, j ) |
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|
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Zip=dxV( i ,j+1,bi,bj)*hFacZ( i ,j+1)*zStar( i ,j+1) |
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Zij=dxV( i , j ,bi,bj)*hFacZ( i , j )*zStar( i , j ) |
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Zpj=dxV(i+1, j ,bi,bj)*hFacZ(i+1, j )*zStar(i+1, j ) |
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|
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C This bit scales the harmonic dissipation operator to be proportional |
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C to the grid-cell area over the time-step. viscAh is then non-dimensional |
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C and should be less than 1/8, for example viscAh=0.01 |
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if (useVariableViscosity) then |
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Dij=Dij*viscA4_D(i,j) |
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Dim=Dim*viscA4_D(i,j-1) |
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Dmj=Dmj*viscA4_D(i-1,j) |
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Zij=Zij*viscA4_Z(i,j) |
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Zip=Zip*viscA4_Z(i,j+1) |
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Zpj=Zpj*viscA4_Z(i+1,j) |
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uD4 = recip_rAw(i,j,bi,bj)*( |
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& ( (Dij-Dmj)*cosFacU(j,bi,bj) ) |
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& -recip_hFacW(i,j,k,bi,bj)*( Zip-Zij ) ) |
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vD4 = recip_rAs(i,j,bi,bj)*( |
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& recip_hFacS(i,j,k,bi,bj)*( (Zpj-Zij)*cosFacV(j,bi,bj) ) |
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& + ( Dij-Dim ) ) |
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else |
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uD4 = recip_rAw(i,j,bi,bj)*( |
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& viscA4*( (Dij-Dmj)*cosFacU(j,bi,bj) ) |
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& -recip_hFacW(i,j,k,bi,bj)*viscA4*( Zip-Zij ) ) |
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vD4 = recip_rAs(i,j,bi,bj)*( |
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& recip_hFacS(i,j,k,bi,bj)*viscA4*( (Zpj-Zij)*cosFacV(j,bi,bj) ) |
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& + viscA4*( Dij-Dim ) ) |
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endif |
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|
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uDissip(i,j) = uD2 - uD4 |
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vDissip(i,j) = vD2 - vD4 |
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|
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ENDDO |
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ENDDO |
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|
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RETURN |
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END |