1 |
C $Header: /u/gcmpack/models/MITgcmUV/pkg/generic_advdiff/gad_dst3fl_adv_x.F,v 1.2 2001/09/05 17:46:03 heimbach Exp $ |
2 |
C $Name: $ |
3 |
|
4 |
#include "GAD_OPTIONS.h" |
5 |
|
6 |
SUBROUTINE GAD_DST3FL_ADV_X( |
7 |
I bi,bj,k,deltaT, |
8 |
I uTrans, uVel, |
9 |
I tracer, |
10 |
O uT, |
11 |
I myThid ) |
12 |
C /==========================================================\ |
13 |
C | SUBROUTINE GAD_DST3FL_ADV_X | |
14 |
C | o Compute Zonal advective Flux of Tracer using | |
15 |
C | 3rd Order DST Sceheme with flux limiting | |
16 |
C |==========================================================| |
17 |
IMPLICIT NONE |
18 |
|
19 |
C == GLobal variables == |
20 |
#include "SIZE.h" |
21 |
#include "GRID.h" |
22 |
#include "GAD.h" |
23 |
|
24 |
C == Routine arguments == |
25 |
INTEGER bi,bj,k |
26 |
_RL deltaT |
27 |
_RL uTrans(1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
28 |
_RL uVel(1-OLx:sNx+OLx,1-OLy:sNy+OLy,Nr,nSx,nSy) |
29 |
_RL tracer(1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
30 |
_RL uT (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
31 |
INTEGER myThid |
32 |
|
33 |
C == Local variables == |
34 |
INTEGER i,j |
35 |
_RL Rjm,Rj,Rjp,cfl,d0,d1,psiP,psiM,thetaP,thetaM |
36 |
|
37 |
DO j=1-Oly,sNy+Oly |
38 |
uT(1-Olx,j)=0. |
39 |
uT(2-Olx,j)=0. |
40 |
uT(sNx+Olx,j)=0. |
41 |
DO i=1-Olx+2,sNx+Olx-1 |
42 |
Rjp=(tracer(i+1,j)-tracer(i,j))*maskW(i+1,j,k,bi,bj) |
43 |
Rj =(tracer(i,j)-tracer(i-1,j))*maskW(i,j,k,bi,bj) |
44 |
Rjm=(tracer(i-1,j)-tracer(i-2,j))*maskW(i-1,j,k,bi,bj) |
45 |
|
46 |
cfl=abs(uVel(i,j,k,bi,bj)*deltaT*recip_dxc(i,j,bi,bj)) |
47 |
d0=(2.-cfl)*(1.-cfl)*oneSixth |
48 |
d1=(1.-cfl*cfl)*oneSixth |
49 |
c thetaP=0. |
50 |
c IF (Rj.NE.0.) thetaP=Rjm/Rj |
51 |
thetaP=Rjm/(1.D-20+Rj) |
52 |
psiP=d0+d1*thetaP |
53 |
psiP=max(0., min(min(1.,psiP),(1.-cfl)/(1.D-20+cfl)*thetaP)) |
54 |
thetaM=Rjp/(1.D-20+Rj) |
55 |
c thetaM=0. |
56 |
c IF (Rj.NE.0.) thetaM=Rjp/Rj |
57 |
psiM=d0+d1*thetaM |
58 |
psiM=max(0., min(min(1.,psiM),(1.-cfl)/(1.D-20+cfl)*thetaM)) |
59 |
uT(i,j)= |
60 |
& 0.5*(uTrans(i,j)+abs(uTrans(i,j))) |
61 |
& *( Tracer(i-1,j) + psiP*Rj ) |
62 |
& +0.5*(uTrans(i,j)-abs(uTrans(i,j))) |
63 |
& *( Tracer( i ,j) - psiM*Rj ) |
64 |
|
65 |
ENDDO |
66 |
ENDDO |
67 |
|
68 |
RETURN |
69 |
END |