model/src/calc_div_ghat.F

C $Header: /u/gcmpack/MITgcm/model/src/calc_div_ghat.F,v 1.21 2006/02/23 20:55:48 jmc Exp $
C $Name:  $

#include "CPP_OPTIONS.h"

CBOP
C     !ROUTINE: CALC_DIV_GHAT
C     !INTERFACE:
      SUBROUTINE CALC_DIV_GHAT(
     I                bi,bj,k,
     U                cg2d_b, cg3d_b,
     I                myThid)
C     !DESCRIPTION: \bv
C     *==========================================================*
C     | S/R CALC_DIV_GHAT
C     | o Form the right hand-side of the surface pressure eqn.
C     *==========================================================*
C     | Right hand side of pressure equation is divergence
C     | of veclocity tendency (GHAT) term along with a relaxation
C     | term equal to the barotropic flow field divergence.
C     *==========================================================*
C     \ev

C     !USES:
      IMPLICIT NONE
C     == Global variables ==
#include "SIZE.h"
#include "EEPARAMS.h"
#include "PARAMS.h"
#include "GRID.h"
#include "DYNVARS.h"

C     !INPUT/OUTPUT PARAMETERS:
C     == Routine arguments ==
C     bi, bj  :: tile indices
C     k       :: Index of layer.
C     cg2d_b  :: Conjugate Gradient 2-D solver : Right-hand side vector
C     cg3d_b  :: Conjugate Gradient 3-D solver : Right-hand side vector
C     myThid  :: Instance number for this call of CALC_DIV_GHAT
      INTEGER bi,bj
      INTEGER k
      _RL cg2d_b(1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)
c#ifdef ALLOW_NONHYDROSTATIC
      _RL cg3d_b(1-OLx:sNx+OLx,1-OLy:sNy+OLy,Nr,nSx,nSy)
c#else
c     _RL cg3d_b(1)
c#endif
      INTEGER myThid

C     !LOCAL VARIABLES:
C     == Local variables ==
C     i,j    :: Loop counters
C     xA, yA :: Cell vertical face areas
C     pf     :: Intermediate array for building RHS source term.
      INTEGER i,j
      _RS xA (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
      _RS yA (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
      _RL pf (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
CEOP

C     Calculate vertical face areas
      DO j=1,sNy+1
        DO i=1,sNx+1
          xA(i,j) = _dyG(i,j,bi,bj)*deepFacC(k)
     &              *drF(k)*_hFacW(i,j,k,bi,bj)*rhoFacC(k)
          yA(i,j) = _dxG(i,j,bi,bj)*deepFacC(k)
     &              *drF(k)*_hFacS(i,j,k,bi,bj)*rhoFacC(k)
        ENDDO
      ENDDO

C--   Pressure equation source term
C     Term is the vertical integral of the divergence of the
C     time tendency terms along with a relaxation term that
C     pulls div(U) + dh/dt back toward zero.

      IF (implicDiv2Dflow.EQ.1.) THEN
C     Fully Implicit treatment of the Barotropic Flow Divergence
        DO j=1,sNy
         DO i=1,sNx+1
          pf(i,j) = xA(i,j)*gU(i,j,k,bi,bj) / deltaTmom
         ENDDO
        ENDDO
      ELSEIF (exactConserv) THEN
c     ELSEIF (nonlinFreeSurf.GT.0) THEN
C     Implicit treatment of the Barotropic Flow Divergence
        DO j=1,sNy
         DO i=1,sNx+1
          pf(i,j) = implicDiv2Dflow
     &             *xA(i,j)*gU(i,j,k,bi,bj) / deltaTmom
         ENDDO
        ENDDO
      ELSE
C     Explicit+Implicit part of the Barotropic Flow Divergence
C      => Filtering of uVel,vVel is necessary
C-- Now the filter are applied in the_correction_step().
C   We have left this code here to indicate where the filters used to be
C   in the algorithm before JMC moved them to after the pressure solver.
C-
C#ifdef ALLOW_ZONAL_FILT
C        IF (zonal_filt_lat.LT.90.) THEN
C          CALL ZONAL_FILTER(
C     &      uVel, hFacW, 1-1, sNy+1, k, k, bi, bj, 1, myThid)
C          CALL ZONAL_FILTER(
C     &      vVel, hFacS, 1-1, sNy+1, k, k, bi, bj, 2, myThid)
C        ENDIF
C#endif
        DO j=1,sNy
         DO i=1,sNx+1
          pf(i,j) = ( implicDiv2Dflow * gU(i,j,k,bi,bj)
     &     + (1. _d 0-implicDiv2Dflow)* uVel(i,j,k,bi,bj)
     &               ) * xA(i,j) / deltaTmom
         ENDDO
        ENDDO
      ENDIF
      DO j=1,sNy
       DO i=1,sNx
        cg2d_b(i,j,bi,bj) = cg2d_b(i,j,bi,bj) +
     &   pf(i+1,j)-pf(i,j)
       ENDDO
      ENDDO

#ifdef ALLOW_NONHYDROSTATIC
      IF (use3Dsolver) THEN
       DO j=1,sNy
        DO i=1,sNx
         cg3d_b(i,j,k,bi,bj) = pf(i+1,j)-pf(i,j)
        ENDDO
       ENDDO
      ENDIF
#endif

      IF (implicDiv2Dflow.EQ.1.) THEN
C     Fully Implicit treatment of the Barotropic Flow Divergence
        DO j=1,sNy+1
         DO i=1,sNx
          pf(i,j) = yA(i,j)*gV(i,j,k,bi,bj) / deltatmom
         ENDDO
        ENDDO
      ELSEIF (exactConserv) THEN
c     ELSEIF (nonlinFreeSurf.GT.0) THEN
C     Implicit treatment of the Barotropic Flow Divergence
        DO j=1,sNy+1
         DO i=1,sNx
          pf(i,j) = implicDiv2Dflow
     &             *yA(i,j)*gV(i,j,k,bi,bj) / deltatmom
         ENDDO
        ENDDO
      ELSE
C     Explicit+Implicit part of the Barotropic Flow Divergence
        DO j=1,sNy+1
         DO i=1,sNx
          pf(i,j) = ( implicDiv2Dflow * gV(i,j,k,bi,bj)
     &     + (1. _d 0-implicDiv2Dflow)* vVel(i,j,k,bi,bj)
     &               ) * yA(i,j) / deltaTmom
         ENDDO
        ENDDO
      ENDIF
      DO j=1,sNy
       DO i=1,sNx
        cg2d_b(i,j,bi,bj) = cg2d_b(i,j,bi,bj) +
     &   pf(i,j+1)-pf(i,j)
       ENDDO
      ENDDO

#ifdef ALLOW_NONHYDROSTATIC
      IF (use3Dsolver) THEN
       DO j=1,sNy
        DO i=1,sNx
         cg3d_b(i,j,k,bi,bj) = cg3d_b(i,j,k,bi,bj) +
     &    pf(i,j+1)-pf(i,j)
        ENDDO
       ENDDO
      ENDIF
#endif

      RETURN
      END
1	jmc	1.22	C $Header: /u/gcmpack/MITgcm/model/src/calc_div_ghat.F,v 1.21 2006/02/23 20:55:48 jmc Exp $
2	jmc	1.12	C $Name: $
3	cnh	1.1
4	cnh	1.6	#include "CPP_OPTIONS.h"
5	edhill	1.19
6	cnh	1.17	CBOP
7			C !ROUTINE: CALC_DIV_GHAT
8			C !INTERFACE:
9			SUBROUTINE CALC_DIV_GHAT(
10	jmc	1.22	I bi,bj,k,
11			U cg2d_b, cg3d_b,
12			I myThid)
13	cnh	1.17	C !DESCRIPTION: \bv
14			C ==========================================================
15	jmc	1.21	C \| S/R CALC_DIV_GHAT
16			C \| o Form the right hand-side of the surface pressure eqn.
17	cnh	1.17	C ==========================================================
18			C \| Right hand side of pressure equation is divergence
19			C \| of veclocity tendency (GHAT) term along with a relaxation
20			C \| term equal to the barotropic flow field divergence.
21			C ==========================================================
22			C \ev
23	cnh	1.1
24	cnh	1.17	C !USES:
25	cnh	1.1	IMPLICIT NONE
26			C == Global variables ==
27			#include "SIZE.h"
28			#include "EEPARAMS.h"
29			#include "PARAMS.h"
30			#include "GRID.h"
31	jmc	1.22	#include "DYNVARS.h"
32	cnh	1.1
33	cnh	1.17	C !INPUT/OUTPUT PARAMETERS:
34	cnh	1.1	C == Routine arguments ==
35	jmc	1.21	C bi, bj :: tile indices
36			C k :: Index of layer.
37			C cg2d_b :: Conjugate Gradient 2-D solver : Right-hand side vector
38	jmc	1.22	C cg3d_b :: Conjugate Gradient 3-D solver : Right-hand side vector
39	jmc	1.21	C myThid :: Instance number for this call of CALC_DIV_GHAT
40	jmc	1.22	INTEGER bi,bj
41	jmc	1.21	INTEGER k
42	jmc	1.13	_RL cg2d_b(1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)
43	jmc	1.22	c#ifdef ALLOW_NONHYDROSTATIC
44			_RL cg3d_b(1-OLx:sNx+OLx,1-OLy:sNy+OLy,Nr,nSx,nSy)
45			c#else
46			c _RL cg3d_b(1)
47			c#endif
48	cnh	1.1	INTEGER myThid
49
50	cnh	1.17	C !LOCAL VARIABLES:
51	cnh	1.1	C == Local variables ==
52	jmc	1.22	C i,j :: Loop counters
53			C xA, yA :: Cell vertical face areas
54			C pf :: Intermediate array for building RHS source term.
55	cnh	1.1	INTEGER i,j
56	jmc	1.22	_RS xA (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
57			_RS yA (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
58	cnh	1.1	_RL pf (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
59	cnh	1.17	CEOP
60	cnh	1.1
61	jmc	1.22	C Calculate vertical face areas
62			DO j=1,sNy+1
63			DO i=1,sNx+1
64			xA(i,j) = _dyG(i,j,bi,bj)*deepFacC(k)
65			& drF(k)_hFacW(i,j,k,bi,bj)*rhoFacC(k)
66			yA(i,j) = _dxG(i,j,bi,bj)*deepFacC(k)
67			& drF(k)_hFacS(i,j,k,bi,bj)*rhoFacC(k)
68			ENDDO
69			ENDDO
70
71	cnh	1.1	C-- Pressure equation source term
72	jmc	1.21	C Term is the vertical integral of the divergence of the
73	cnh	1.1	C time tendency terms along with a relaxation term that
74			C pulls div(U) + dh/dt back toward zero.
75
76	jmc	1.16	IF (implicDiv2Dflow.EQ.1.) THEN
77	jmc	1.12	C Fully Implicit treatment of the Barotropic Flow Divergence
78			DO j=1,sNy
79			DO i=1,sNx+1
80	jmc	1.18	pf(i,j) = xA(i,j)*gU(i,j,k,bi,bj) / deltaTmom
81	jmc	1.12	ENDDO
82			ENDDO
83	jmc	1.16	ELSEIF (exactConserv) THEN
84			c ELSEIF (nonlinFreeSurf.GT.0) THEN
85			C Implicit treatment of the Barotropic Flow Divergence
86			DO j=1,sNy
87			DO i=1,sNx+1
88	jmc	1.21	pf(i,j) = implicDiv2Dflow
89	jmc	1.18	& xA(i,j)gU(i,j,k,bi,bj) / deltaTmom
90	jmc	1.16	ENDDO
91			ENDDO
92	jmc	1.12	ELSE
93			C Explicit+Implicit part of the Barotropic Flow Divergence
94			C => Filtering of uVel,vVel is necessary
95	jmc	1.16	C-- Now the filter are applied in the_correction_step().
96			C We have left this code here to indicate where the filters used to be
97	jmc	1.21	C in the algorithm before JMC moved them to after the pressure solver.
98	jmc	1.22	C-
99	jmc	1.16	C#ifdef ALLOW_ZONAL_FILT
100	jmc	1.22	C IF (zonal_filt_lat.LT.90.) THEN
101	jmc	1.16	C CALL ZONAL_FILTER(
102			C & uVel, hFacW, 1-1, sNy+1, k, k, bi, bj, 1, myThid)
103			C CALL ZONAL_FILTER(
104			C & vVel, hFacS, 1-1, sNy+1, k, k, bi, bj, 2, myThid)
105			C ENDIF
106			C#endif
107	jmc	1.12	DO j=1,sNy
108			DO i=1,sNx+1
109	jmc	1.18	pf(i,j) = ( implicDiv2Dflow * gU(i,j,k,bi,bj)
110	jmc	1.22	& + (1. _d 0-implicDiv2Dflow)* uVel(i,j,k,bi,bj)
111	jmc	1.12	& ) * xA(i,j) / deltaTmom
112			ENDDO
113			ENDDO
114			ENDIF
115	cnh	1.1	DO j=1,sNy
116			DO i=1,sNx
117	adcroft	1.8	cg2d_b(i,j,bi,bj) = cg2d_b(i,j,bi,bj) +
118	cnh	1.1	& pf(i+1,j)-pf(i,j)
119			ENDDO
120			ENDDO
121
122	adcroft	1.8	#ifdef ALLOW_NONHYDROSTATIC
123	jmc	1.21	IF (use3Dsolver) THEN
124	adcroft	1.8	DO j=1,sNy
125			DO i=1,sNx
126			cg3d_b(i,j,k,bi,bj) = pf(i+1,j)-pf(i,j)
127			ENDDO
128			ENDDO
129			ENDIF
130			#endif
131
132	jmc	1.16	IF (implicDiv2Dflow.EQ.1.) THEN
133	jmc	1.12	C Fully Implicit treatment of the Barotropic Flow Divergence
134			DO j=1,sNy+1
135			DO i=1,sNx
136	jmc	1.18	pf(i,j) = yA(i,j)*gV(i,j,k,bi,bj) / deltatmom
137	jmc	1.16	ENDDO
138			ENDDO
139			ELSEIF (exactConserv) THEN
140			c ELSEIF (nonlinFreeSurf.GT.0) THEN
141			C Implicit treatment of the Barotropic Flow Divergence
142			DO j=1,sNy+1
143			DO i=1,sNx
144			pf(i,j) = implicDiv2Dflow
145	jmc	1.18	& yA(i,j)gV(i,j,k,bi,bj) / deltatmom
146	jmc	1.12	ENDDO
147			ENDDO
148			ELSE
149			C Explicit+Implicit part of the Barotropic Flow Divergence
150			DO j=1,sNy+1
151			DO i=1,sNx
152	jmc	1.18	pf(i,j) = ( implicDiv2Dflow * gV(i,j,k,bi,bj)
153	jmc	1.22	& + (1. _d 0-implicDiv2Dflow)* vVel(i,j,k,bi,bj)
154	jmc	1.12	& ) * yA(i,j) / deltaTmom
155			ENDDO
156			ENDDO
157			ENDIF
158	cnh	1.1	DO j=1,sNy
159			DO i=1,sNx
160	adcroft	1.8	cg2d_b(i,j,bi,bj) = cg2d_b(i,j,bi,bj) +
161	cnh	1.1	& pf(i,j+1)-pf(i,j)
162			ENDDO
163			ENDDO
164	cnh	1.4
165	adcroft	1.8	#ifdef ALLOW_NONHYDROSTATIC
166	jmc	1.21	IF (use3Dsolver) THEN
167	adcroft	1.8	DO j=1,sNy
168			DO i=1,sNx
169			cg3d_b(i,j,k,bi,bj) = cg3d_b(i,j,k,bi,bj) +
170			& pf(i,j+1)-pf(i,j)
171			ENDDO
172			ENDDO
173			ENDIF
174			#endif
175	cnh	1.1
176			RETURN
177			END