/[MITgcm]/MITgcm/pkg/generic_advdiff/gad_dst3fl_adv_r.F
ViewVC logotype

Annotation of /MITgcm/pkg/generic_advdiff/gad_dst3fl_adv_r.F

Parent Directory Parent Directory | Revision Log Revision Log | View Revision Graph Revision Graph


Revision 1.8 - (hide annotations) (download)
Mon Jun 19 14:40:43 2006 UTC (17 years, 11 months ago) by jmc
Branch: MAIN
CVS Tags: checkpoint58m_post, checkpoint58o_post, checkpoint58p_post, checkpoint58q_post, checkpoint58r_post, checkpoint58n_post, checkpoint58k_post, checkpoint58l_post
Changes since 1.7: +3 -3 lines
DST advection S/R : use local copy of velocity to compute CFL

1 jmc 1.8 C $Header: /u/gcmpack/MITgcm/pkg/generic_advdiff/gad_dst3fl_adv_r.F,v 1.7 2006/06/18 23:31:35 jmc Exp $
2 adcroft 1.3 C $Name: $
3 adcroft 1.1
4     #include "GAD_OPTIONS.h"
5    
6 jmc 1.6 CBOP
7     C !ROUTINE: GAD_DST3FL_ADV_R
8    
9     C !INTERFACE: ==========================================================
10 jmc 1.7 SUBROUTINE GAD_DST3FL_ADV_R(
11 jmc 1.6 I bi,bj,k,dTarg,
12 jmc 1.7 I rTrans, wFld,
13 adcroft 1.1 I tracer,
14     O wT,
15     I myThid )
16 jmc 1.6
17     C !DESCRIPTION:
18     C Calculates the area integrated vertical flux due to advection of a tracer
19     C using 3rd Order DST Scheme with flux limiting
20    
21     C !USES: ===============================================================
22 adcroft 1.1 IMPLICIT NONE
23    
24     C == GLobal variables ==
25     #include "SIZE.h"
26     #include "GRID.h"
27     #include "GAD.h"
28    
29     C == Routine arguments ==
30 jmc 1.6 C !INPUT PARAMETERS: ===================================================
31     C bi,bj :: tile indices
32     C k :: vertical level
33     C deltaTloc :: local time-step (s)
34     C rTrans :: vertical volume transport
35 jmc 1.7 C wFld :: vertical flow
36 jmc 1.6 C tracer :: tracer field
37     C myThid :: thread number
38     INTEGER bi,bj,k
39 adcroft 1.1 _RL dTarg
40     _RL rTrans(1-OLx:sNx+OLx,1-OLy:sNy+OLy)
41 jmc 1.7 _RL wFld (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
42 jmc 1.6 _RL tracer(1-OLx:sNx+OLx,1-OLy:sNy+OLy,Nr)
43     INTEGER myThid
44    
45     C !OUTPUT PARAMETERS: ==================================================
46     C wT :: vertical advective flux
47 adcroft 1.1 _RL wT (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
48    
49     C == Local variables ==
50 jmc 1.6 C !LOCAL VARIABLES: ====================================================
51     C i,j :: loop indices
52     C km1 :: =max( k-1 , 1 )
53 jmc 1.7 C wLoc :: velocity, vertical component
54 jmc 1.6 C wCFL :: Courant-Friedrich-Levy number
55     INTEGER i,j,kp1,km1,km2
56 adcroft 1.1 _RL Rjm,Rj,Rjp,cfl,d0,d1
57     _RL psiP,psiM,thetaP,thetaM
58 jmc 1.7 _RL wLoc
59 jmc 1.5 _RL thetaMax
60     PARAMETER( thetaMax = 1.D+20 )
61 adcroft 1.1
62     km2=MAX(1,k-2)
63     km1=MAX(1,k-1)
64     kp1=MIN(Nr,k+1)
65    
66     DO j=1-Oly,sNy+Oly
67     DO i=1-Olx,sNx+Olx
68 jmc 1.6 Rjp=(tracer(i,j,k)-tracer(i,j,kp1))
69     & *maskC(i,j,kp1,bi,bj)
70     Rj =(tracer(i,j,km1)-tracer(i,j,k))
71     & *maskC(i,j,k,bi,bj)*maskC(i,j,km1,bi,bj)
72     Rjm=(tracer(i,j,km2)-tracer(i,j,km1))
73     & *maskC(i,j,km1,bi,bj)
74 adcroft 1.1
75 jmc 1.8 wLoc = wFld(i,j)
76     c wLoc = rTrans(i,j)*recip_rA(i,j,bi,bj)
77 jmc 1.7 cfl=abs(wLoc*dTarg*recip_drC(k))
78 jmc 1.5 d0=(2. _d 0 -cfl)*(1. _d 0 -cfl)*oneSixth
79     d1=(1. _d 0 -cfl*cfl)*oneSixth
80    
81     C- the old version: can produce overflow, division by zero,
82     C and is wrong for tracer with low concentration:
83     c thetaP=Rjm/(1.D-20+Rj)
84     c thetaM=Rjp/(1.D-20+Rj)
85     C- the right expression, but not bounded:
86 heimbach 1.2 c thetaP=0.D0
87 jmc 1.5 c thetaM=0.D0
88 heimbach 1.2 c IF (Rj.NE.0.D0) thetaP=Rjm/Rj
89 jmc 1.5 c IF (Rj.NE.0.D0) thetaM=Rjp/Rj
90     C- prevent |thetaP,M| to reach too big value:
91     IF ( ABS(Rj)*thetaMax .LE. ABS(Rjm) ) THEN
92     thetaP=SIGN(thetaMax,Rjm*Rj)
93     ELSE
94     thetaP=Rjm/Rj
95     ENDIF
96     IF ( ABS(Rj)*thetaMax .LE. ABS(Rjp) ) THEN
97     thetaM=SIGN(thetaMax,Rjp*Rj)
98     ELSE
99     thetaM=Rjp/Rj
100     ENDIF
101    
102 adcroft 1.1 psiP=d0+d1*thetaP
103 jmc 1.5 psiP=MAX(0. _d 0,MIN(MIN(1. _d 0,psiP),
104     & thetaP*(1. _d 0 -cfl)/(cfl+1. _d -20) ))
105 adcroft 1.1 psiM=d0+d1*thetaM
106 jmc 1.5 psiM=MAX(0. _d 0,MIN(MIN(1. _d 0,psiM),
107     & thetaM*(1. _d 0 -cfl)/(cfl+1. _d -20) ))
108    
109 adcroft 1.1 wT(i,j)=
110     & 0.5*(rTrans(i,j)+abs(rTrans(i,j)))
111 jmc 1.6 & *( tracer(i,j, k ) + psiM*Rj )
112 adcroft 1.1 & +0.5*(rTrans(i,j)-abs(rTrans(i,j)))
113 jmc 1.6 & *( tracer(i,j,km1) - psiP*Rj )
114 adcroft 1.1
115     ENDDO
116     ENDDO
117    
118     RETURN
119     END

  ViewVC Help
Powered by ViewVC 1.1.22