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C $Header: /u/gcmpack/MITgcm/pkg/generic_advdiff/gad_dst3fl_adv_x.F,v 1.4 2001/11/08 23:39:34 heimbach Exp $ |
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C $Name: $ |
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|
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#include "GAD_OPTIONS.h" |
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|
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SUBROUTINE GAD_DST3FL_ADV_X( |
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I bi,bj,k,deltaT, |
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I uTrans, uVel, |
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I tracer, |
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O uT, |
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I myThid ) |
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C /==========================================================\ |
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C | SUBROUTINE GAD_DST3FL_ADV_X | |
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C | o Compute Zonal advective Flux of Tracer using | |
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C | 3rd Order DST Sceheme with flux limiting | |
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C |==========================================================| |
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IMPLICIT NONE |
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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 "GAD.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 deltaT |
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_RL uTrans(1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL uVel(1-OLx:sNx+OLx,1-OLy:sNy+OLy,Nr,nSx,nSy) |
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_RL tracer(1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL uT (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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C uFld :: velocity [m/s], zonal component |
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INTEGER i,j |
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_RL Rjm,Rj,Rjp,cfl,d0,d1,psiP,psiM,thetaP,thetaM |
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_RL uFld |
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|
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DO j=1-Oly,sNy+Oly |
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uT(1-Olx,j)=0.D0 |
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uT(2-Olx,j)=0.D0 |
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uT(sNx+Olx,j)=0.D0 |
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DO i=1-Olx+2,sNx+Olx-1 |
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Rjp=(tracer(i+1,j)-tracer(i,j))*maskW(i+1,j,k,bi,bj) |
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Rj =(tracer(i,j)-tracer(i-1,j))*maskW(i,j,k,bi,bj) |
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Rjm=(tracer(i-1,j)-tracer(i-2,j))*maskW(i-1,j,k,bi,bj) |
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|
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c uFld = uVel(i,j,k,bi,bj) |
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uFld = uTrans(i,j)*recip_dyG(i,j,bi,bj) |
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& *recip_drF(k)*recip_hFacW(i,j,k,bi,bj) |
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cfl=abs(uFld*deltaT*recip_dxC(i,j,bi,bj)) |
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d0=(2.D0-cfl)*(1.D0-cfl)*oneSixth |
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d1=(1.D0-cfl*cfl)*oneSixth |
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c thetaP=0.D0 |
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c IF (Rj.NE.0.D0) thetaP=Rjm/Rj |
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thetaP=Rjm/(1.D-20+Rj) |
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psiP=d0+d1*thetaP |
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psiP=max(0.D0, min(min(1.D0,psiP), |
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& (1.D0-cfl)/(1.D-20+cfl)*thetaP)) |
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thetaM=Rjp/(1.D-20+Rj) |
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c thetaM=0.D0 |
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c IF (Rj.NE.0.D0) thetaM=Rjp/Rj |
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psiM=d0+d1*thetaM |
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psiM=max(0.D0, min(min(1.D0,psiM), |
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& (1.D0-cfl)/(1.D-20+cfl)*thetaM)) |
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uT(i,j)= |
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& 0.5*(uTrans(i,j)+abs(uTrans(i,j))) |
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& *( Tracer(i-1,j) + psiP*Rj ) |
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& +0.5*(uTrans(i,j)-abs(uTrans(i,j))) |
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& *( Tracer( i ,j) - psiM*Rj ) |
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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 |