C $Header: /u/gcmpack/MITgcm/model/src/solve_for_pressure.F,v 1.83 2017/03/24 15:41:19 jmc Exp $
C $Name: $
#include "PACKAGES_CONFIG.h"
#include "CPP_OPTIONS.h"
CBOP
C !ROUTINE: SOLVE_FOR_PRESSURE
C !INTERFACE:
SUBROUTINE SOLVE_FOR_PRESSURE( myTime, myIter, myThid )
C !DESCRIPTION: \bv
C *==========================================================*
C | SUBROUTINE SOLVE_FOR_PRESSURE
C | o Controls inversion of two and/or three-dimensional
C | elliptic problems for the pressure field.
C *==========================================================*
C \ev
C !USES:
IMPLICIT NONE
C == Global variables
#include "SIZE.h"
#include "EEPARAMS.h"
#include "PARAMS.h"
#include "GRID.h"
#include "SURFACE.h"
#include "FFIELDS.h"
#include "DYNVARS.h"
#include "SOLVE_FOR_PRESSURE.h"
#ifdef ALLOW_NONHYDROSTATIC
#include "SOLVE_FOR_PRESSURE3D.h"
#include "NH_VARS.h"
#endif
#ifdef ALLOW_CD_CODE
#include "CD_CODE_VARS.h"
#endif
C === Functions ====
LOGICAL DIFFERENT_MULTIPLE
EXTERNAL
#ifdef ALLOW_DIAGNOSTICS
LOGICAL DIAGNOSTICS_IS_ON
EXTERNAL
#endif /* ALLOW_DIAGNOSTICS */
C !INPUT/OUTPUT PARAMETERS:
C == Routine arguments ==
C myTime :: Current time in simulation
C myIter :: Current iteration number in simulation
C myThid :: Thread number for this instance of SOLVE_FOR_PRESSURE
_RL myTime
INTEGER myIter
INTEGER myThid
C !LOCAL VARIABLES:
C == Local variables ==
INTEGER i,j,k,bi,bj
INTEGER ks
INTEGER numIters, nIterMin
_RL firstResidual, minResidualSq, lastResidual
_RL tmpFac
_RL sumEmP, tileEmP(nSx,nSy)
LOGICAL putPmEinXvector
INTEGER ioUnit
CHARACTER*(MAX_LEN_MBUF) msgBuf
#ifdef ALLOW_NONHYDROSTATIC
LOGICAL zeroPsNH, zeroMeanPnh, oldFreeSurfTerm
#else
_RL cg3d_b(1)
#endif
#ifdef ALLOW_DIAGNOSTICS
CHARACTER*8 diagName
_RL tmpVar (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
#endif /* ALLOW_DIAGNOSTICS */
CEOP
#ifdef ALLOW_NONHYDROSTATIC
zeroPsNH = .FALSE.
c zeroPsNH = use3Dsolver .AND. exactConserv
c & .AND. select_rStar.EQ.0
zeroMeanPnh = .FALSE.
c zeroMeanPnh = use3Dsolver .AND. select_rStar.NE.0
c oldFreeSurfTerm = use3Dsolver .AND. select_rStar.EQ.0
c & .AND. .NOT.zeroPsNH
oldFreeSurfTerm = use3Dsolver .AND. .NOT.exactConserv
#else
cg3d_b(1) = 0.
#endif
C deepAtmosphere & useRealFreshWaterFlux: only valid if deepFac2F(ksurf)=1
C anelastic (always Z-coordinate):
C 1) assume that rhoFacF(1)=1 (and ksurf == 1);
C (this reduces the number of lines of code to modify)
C 2) (a) 2-D continuity eq. compute div. of mass transport (<- add rhoFac)
C (b) gradient of surf.Press in momentum eq. (<- add 1/rhoFac)
C => 2 factors cancel in elliptic eq. for Phi_s ,
C but 1rst factor(a) remains in RHS cg2d_b.
C-- Initialise the Vector solution with etaN + deltaT*Global_mean_PmE
C instead of simply etaN ; This can speed-up the solver convergence in
C the case where |Global_mean_PmE| is large.
putPmEinXvector = .FALSE.
c putPmEinXvector = useRealFreshWaterFlux.AND.fluidIsWater
IF ( myIter.EQ.1+nIter0 .AND. debugLevel .GE. debLevA ) THEN
_BEGIN_MASTER( myThid )
ioUnit = standardMessageUnit
WRITE(msgBuf,'(2A,L5)') 'SOLVE_FOR_PRESSURE:',
& ' putPmEinXvector =', putPmEinXvector
CALL PRINT_MESSAGE( msgBuf, ioUnit, SQUEEZE_RIGHT, myThid )
#ifdef ALLOW_NONHYDROSTATIC
WRITE(msgBuf,'(A,2(A,L5))') 'SOLVE_FOR_PRESSURE:',
& ' zeroPsNH=', zeroPsNH, ' , zeroMeanPnh=', zeroMeanPnh
CALL PRINT_MESSAGE( msgBuf, ioUnit, SQUEEZE_RIGHT, myThid )
WRITE(msgBuf,'(2A,L5)') 'SOLVE_FOR_PRESSURE:',
& ' oldFreeSurfTerm =', oldFreeSurfTerm
CALL PRINT_MESSAGE( msgBuf, ioUnit, SQUEEZE_RIGHT, myThid )
#endif
_END_MASTER( myThid )
ENDIF
C-- Save previous solution & Initialise Vector solution and source term :
sumEmP = 0.
DO bj=myByLo(myThid),myByHi(myThid)
DO bi=myBxLo(myThid),myBxHi(myThid)
DO j=1-OLy,sNy+OLy
DO i=1-OLx,sNx+OLx
#ifdef ALLOW_CD_CODE
etaNm1(i,j,bi,bj) = etaN(i,j,bi,bj)
#endif
cg2d_x(i,j,bi,bj) = Bo_surf(i,j,bi,bj)*etaN(i,j,bi,bj)
cg2d_b(i,j,bi,bj) = 0.
ENDDO
ENDDO
IF (useRealFreshWaterFlux.AND.fluidIsWater) THEN
tmpFac = freeSurfFac*mass2rUnit*implicDiv2DFlow
DO j=1,sNy
DO i=1,sNx
cg2d_b(i,j,bi,bj) =
& tmpFac*_rA(i,j,bi,bj)*EmPmR(i,j,bi,bj)/deltaTMom
& *maskInC(i,j,bi,bj)
ENDDO
ENDDO
ENDIF
IF ( putPmEinXvector ) THEN
tileEmP(bi,bj) = 0.
DO j=1,sNy
DO i=1,sNx
tileEmP(bi,bj) = tileEmP(bi,bj)
& + rA(i,j,bi,bj)*EmPmR(i,j,bi,bj)
& *maskInC(i,j,bi,bj)
ENDDO
ENDDO
ENDIF
ENDDO
ENDDO
IF ( putPmEinXvector ) THEN
CALL GLOBAL_SUM_TILE_RL( tileEmP, sumEmP, myThid )
ENDIF
DO bj=myByLo(myThid),myByHi(myThid)
DO bi=myBxLo(myThid),myBxHi(myThid)
IF ( putPmEinXvector ) THEN
tmpFac = 0.
IF (globalArea.GT.0.) tmpFac =
& freeSurfFac*deltaTFreeSurf*mass2rUnit*sumEmP/globalArea
DO j=1,sNy
DO i=1,sNx
cg2d_x(i,j,bi,bj) = cg2d_x(i,j,bi,bj)
& - tmpFac*Bo_surf(i,j,bi,bj)
ENDDO
ENDDO
ENDIF
C- RHS: similar to the divergence of the vertically integrated mass transport:
C del_i { Sum_k [ rhoFac.(dr.hFac).(dy.deepFac).(u*) ] } / deltaT
DO k=Nr,1,-1
CALL CALC_DIV_GHAT(
I bi,bj,k,
U cg2d_b, cg3d_b,
I myThid )
ENDDO
ENDDO
ENDDO
DO bj=myByLo(myThid),myByHi(myThid)
DO bi=myBxLo(myThid),myBxHi(myThid)
#ifdef ALLOW_NONHYDROSTATIC
IF ( oldFreeSurfTerm ) THEN
C-- Add source term arising from w=d/dt (p_s + p_nh)
DO j=1,sNy
DO i=1,sNx
ks = kSurfC(i,j,bi,bj)
IF ( ks.LE.Nr ) THEN
cg2d_b(i,j,bi,bj) = cg2d_b(i,j,bi,bj)
& -freeSurfFac*_rA(i,j,bi,bj)*deepFac2F(ks)
& /deltaTMom/deltaTFreeSurf
& *( etaN(i,j,bi,bj)
& +phi_nh(i,j,ks,bi,bj)*recip_Bo(i,j,bi,bj) )
cg3d_b(i,j,ks,bi,bj) = cg3d_b(i,j,ks,bi,bj)
& -freeSurfFac*_rA(i,j,bi,bj)*deepFac2F(ks)
& /deltaTMom/deltaTFreeSurf
& *( etaN(i,j,bi,bj)
& +phi_nh(i,j,ks,bi,bj)*recip_Bo(i,j,bi,bj) )
ENDIF
ENDDO
ENDDO
ELSEIF ( exactConserv ) THEN
#else
C-- Add source term arising from w=d/dt (p_s)
IF ( exactConserv ) THEN
#endif /* ALLOW_NONHYDROSTATIC */
DO j=1,sNy
DO i=1,sNx
ks = kSurfC(i,j,bi,bj)
cg2d_b(i,j,bi,bj) = cg2d_b(i,j,bi,bj)
& -freeSurfFac*_rA(i,j,bi,bj)*deepFac2F(ks)
& /deltaTMom/deltaTFreeSurf
& * etaH(i,j,bi,bj)
ENDDO
ENDDO
ELSE
DO j=1,sNy
DO i=1,sNx
ks = kSurfC(i,j,bi,bj)
cg2d_b(i,j,bi,bj) = cg2d_b(i,j,bi,bj)
& -freeSurfFac*_rA(i,j,bi,bj)*deepFac2F(ks)
& /deltaTMom/deltaTFreeSurf
& * etaN(i,j,bi,bj)
ENDDO
ENDDO
ENDIF
#ifdef ALLOW_OBCS
C- Note: solver matrix is trivial outside OB region (main diagonal only)
C => no real need to reset RHS (=cg2d_b) & cg2d_x, except that:
C a) normalisation is fct of Max(RHS), which can be large ouside OB region
C (would be different if we were solving for increment of eta/g
C instead of directly for eta/g).
C => need to reset RHS to ensure that interior solution does not depend
C on ouside OB region.
C b) provide directly the trivial solution cg2d_x == 0 for outside OB region
C (=> no residual => no effect on solver convergence and interior solution)
IF (useOBCS) THEN
DO j=1,sNy
DO i=1,sNx
cg2d_b(i,j,bi,bj) = cg2d_b(i,j,bi,bj)*maskInC(i,j,bi,bj)
cg2d_x(i,j,bi,bj) = cg2d_x(i,j,bi,bj)*maskInC(i,j,bi,bj)
ENDDO
ENDDO
ENDIF
#endif /* ALLOW_OBCS */
C- end bi,bj loops
ENDDO
ENDDO
#ifdef ALLOW_DEBUG
IF ( debugLevel .GE. debLevD ) THEN
CALL DEBUG_STATS_RL(1,cg2d_b,'cg2d_b (SOLVE_FOR_PRESSURE)',
& myThid)
ENDIF
#endif
IF ( DIFFERENT_MULTIPLE(diagFreq, myTime, deltaTClock) ) THEN
CALL WRITE_FLD_XY_RL( 'cg2d_b', 'I10', cg2d_b, myIter, myThid )
ENDIF
C-- Find the surface pressure using a two-dimensional conjugate
C gradient solver. See CG2D.h for the interface to this routine.
C In rare cases of a poor solver convergence, better to select the
C solver minimum-residual solution (instead of the last-iter solution)
C by setting cg2dUseMinResSol=1 (<-> nIterMin=0 in input)
numIters = cg2dMaxIters
nIterMin = cg2dUseMinResSol - 1
c CALL TIMER_START('CG2D [SOLVE_FOR_PRESSURE]',myThid)
#ifdef DISCONNECTED_TILES
C-- Call the not-self-adjoint version of cg2d
CALL CG2D_EX0(
U cg2d_b, cg2d_x,
O firstResidual, minResidualSq, lastResidual,
U numIters, nIterMin,
I myThid )
#else /* not DISCONNECTED_TILES = default */
#ifdef ALLOW_CG2D_NSA
C-- Call the not-self-adjoint version of cg2d
CALL CG2D_NSA(
U cg2d_b, cg2d_x,
O firstResidual, minResidualSq, lastResidual,
U numIters, nIterMin,
I myThid )
#else /* not ALLOW_CG2D_NSA = default */
#ifdef ALLOW_SRCG
IF ( useSRCGSolver ) THEN
C-- Call the single reduce CG solver
CALL CG2D_SR(
U cg2d_b, cg2d_x,
O firstResidual, minResidualSq, lastResidual,
U numIters, nIterMin,
I myThid )
ELSE
#else
IF (.TRUE.) THEN
C-- Call the default CG solver
#endif /* ALLOW_SRCG */
CALL CG2D(
U cg2d_b, cg2d_x,
O firstResidual, minResidualSq, lastResidual,
U numIters, nIterMin,
I myThid )
ENDIF
#endif /* ALLOW_CG2D_NSA */
#endif /* DISCONNECTED_TILES */
_EXCH_XY_RL( cg2d_x, myThid )
c CALL TIMER_STOP ('CG2D [SOLVE_FOR_PRESSURE]',myThid)
#ifdef ALLOW_DEBUG
IF ( debugLevel .GE. debLevD ) THEN
CALL DEBUG_STATS_RL(1,cg2d_x,'cg2d_x (SOLVE_FOR_PRESSURE)',
& myThid)
ENDIF
#endif
C- dump CG2D output at monitorFreq (to reduce size of STD-OUTPUT files) :
IF ( DIFFERENT_MULTIPLE(monitorFreq,myTime,deltaTClock)
& ) THEN
IF ( debugLevel .GE. debLevA ) THEN
_BEGIN_MASTER( myThid )
WRITE(msgBuf,'(A20,1PE23.14)') 'cg2d_init_res =',firstResidual
CALL PRINT_MESSAGE(msgBuf,standardMessageUnit,SQUEEZE_RIGHT,1)
WRITE(msgBuf,'(A27,2I8)')
& 'cg2d_iters(min,last) =', nIterMin, numIters
CALL PRINT_MESSAGE(msgBuf,standardMessageUnit,SQUEEZE_RIGHT,1)
IF ( minResidualSq.GE.0. ) THEN
minResidualSq = SQRT(minResidualSq)
WRITE(msgBuf,'(A20,1PE23.14)') 'cg2d_min_res =',minResidualSq
CALL PRINT_MESSAGE(msgBuf,standardMessageUnit,SQUEEZE_RIGHT,1)
ENDIF
WRITE(msgBuf,'(A20,1PE23.14)') 'cg2d_last_res =',lastResidual
CALL PRINT_MESSAGE(msgBuf,standardMessageUnit,SQUEEZE_RIGHT,1)
_END_MASTER( myThid )
ENDIF
ENDIF
#ifdef ALLOW_DIAGNOSTICS
C-- Fill diagnostics
IF ( useDiagnostics .AND. implicSurfPress.NE.oneRL ) THEN
diagName = 'PHI_SURF'
IF ( DIAGNOSTICS_IS_ON(diagName,myThid) ) THEN
DO bj=myByLo(myThid),myByHi(myThid)
DO bi=myBxLo(myThid),myBxHi(myThid)
DO j=1-OLy,sNy+OLy
DO i=1-OLx,sNx+OLx
tmpVar(i,j) = implicSurfPress * cg2d_x(i,j,bi,bj)
& + (oneRL - implicSurfPress)* Bo_surf(i,j,bi,bj)
& * etaN(i,j,bi,bj)
ENDDO
ENDDO
CALL DIAGNOSTICS_FILL( tmpVar,diagName,1,1,2,bi,bj,myThid )
ENDDO
ENDDO
ENDIF
ELSEIF ( useDiagnostics ) THEN
CALL DIAGNOSTICS_FILL( cg2d_x,'PHI_SURF', 0,1, 0,1,1, myThid )
ENDIF
#endif /* ALLOW_DIAGNOSTICS */
C-- Transfert the 2D-solution to "etaN" :
DO bj=myByLo(myThid),myByHi(myThid)
DO bi=myBxLo(myThid),myBxHi(myThid)
DO j=1-OLy,sNy+OLy
DO i=1-OLx,sNx+OLx
etaN(i,j,bi,bj) = recip_Bo(i,j,bi,bj)*cg2d_x(i,j,bi,bj)
ENDDO
ENDDO
ENDDO
ENDDO
#ifdef ALLOW_NONHYDROSTATIC
IF ( use3Dsolver ) THEN
IF ( DIFFERENT_MULTIPLE(diagFreq, myTime, deltaTClock) ) THEN
CALL WRITE_FLD_XY_RL( 'cg2d_x','I10', cg2d_x, myIter, myThid )
ENDIF
C-- Solve for a three-dimensional pressure term (NH or IGW or both ).
C see CG3D.h for the interface to this routine.
C-- Finish updating cg3d_b: 1) Add EmPmR contribution to top level cg3d_b:
C 2) Update or Add free-surface contribution
C 3) increment in horiz velocity due to new cg2d_x
C 4) add vertical velocity contribution.
CALL PRE_CG3D(
I oldFreeSurfTerm,
I cg2d_x,
U cg3d_b,
I myTime, myIter, myThid )
#ifdef ALLOW_DEBUG
IF ( debugLevel .GE. debLevD ) THEN
CALL DEBUG_STATS_RL(Nr,cg3d_b,'cg3d_b (SOLVE_FOR_PRESSURE)',
& myThid)
ENDIF
#endif
IF ( DIFFERENT_MULTIPLE( diagFreq, myTime, deltaTClock) ) THEN
CALL WRITE_FLD_XYZ_RL('cg3d_b','I10', cg3d_b, myIter,myThid )
ENDIF
firstResidual=0.
lastResidual=0.
numIters=cg3dMaxIters
CALL TIMER_START('CG3D [SOLVE_FOR_PRESSURE]',myThid)
#ifdef DISCONNECTED_TILES
CALL CG3D_EX0(
U cg3d_b, phi_nh,
O firstResidual, lastResidual,
U numIters,
I myIter, myThid )
#else /* not DISCONNECTED_TILES = default */
CALL CG3D(
U cg3d_b, phi_nh,
O firstResidual, lastResidual,
U numIters,
I myIter, myThid )
#endif /* DISCONNECTED_TILES */
_EXCH_XYZ_RL( phi_nh, myThid )
CALL TIMER_STOP ('CG3D [SOLVE_FOR_PRESSURE]',myThid)
IF ( DIFFERENT_MULTIPLE(monitorFreq,myTime,deltaTClock)
& ) THEN
IF ( debugLevel .GE. debLevA ) THEN
_BEGIN_MASTER( myThid )
WRITE(msgBuf,'(A20,1PE23.14)') 'cg3d_init_res =',firstResidual
CALL PRINT_MESSAGE(msgBuf,standardMessageUnit,SQUEEZE_RIGHT,1)
WRITE(msgBuf,'(A27,I16)') 'cg3d_iters (last) = ',numIters
CALL PRINT_MESSAGE(msgBuf,standardMessageUnit,SQUEEZE_RIGHT,1)
WRITE(msgBuf,'(A20,1PE23.14)') 'cg3d_last_res =',lastResidual
CALL PRINT_MESSAGE(msgBuf,standardMessageUnit,SQUEEZE_RIGHT,1)
_END_MASTER( myThid )
ENDIF
ENDIF
C-- Separate the Hydrostatic Surface Pressure adjusment (=> put it in dPhiNH)
C from the Non-hydrostatic pressure (since cg3d_x contains both contribution)
IF ( nonHydrostatic .AND. exactConserv ) THEN
IF ( DIFFERENT_MULTIPLE( diagFreq, myTime, deltaTClock) ) THEN
CALL WRITE_FLD_XYZ_RL('cg3d_x','I10', phi_nh, myIter,myThid )
ENDIF
CALL POST_CG3D(
I zeroPsNH, zeroMeanPnh,
I myTime, myIter, myThid )
ENDIF
ENDIF
#endif /* ALLOW_NONHYDROSTATIC */
#ifdef ALLOW_SHOWFLOPS
CALL SHOWFLOPS_INSOLVE( myThid)
#endif
RETURN
END