| 1 |
C $Header: /u/gcmpack/MITgcm/pkg/mom_common/mom_u_bottomdrag.F,v 1.10 2012/04/26 21:23:20 heimbach Exp $ |
| 2 |
C $Name: $ |
| 3 |
|
| 4 |
#include "MOM_COMMON_OPTIONS.h" |
| 5 |
|
| 6 |
CBOP |
| 7 |
C !ROUTINE: MOM_U_BOTTOMDRAG |
| 8 |
|
| 9 |
C !INTERFACE: ========================================================== |
| 10 |
SUBROUTINE MOM_U_BOTTOMDRAG( |
| 11 |
I bi,bj,k, |
| 12 |
I uFld, KE, KappaRU, |
| 13 |
O uDragTerms, |
| 14 |
I myThid) |
| 15 |
|
| 16 |
C !DESCRIPTION: |
| 17 |
C Calculates the drag due to friction and the no-slip condition at bottom: |
| 18 |
C \begin{equation*} |
| 19 |
C G^u_{drag} = - \frac{1}{\Delta r_f} ( r_b + C_D |v| + \frac{2}{\Delta r_c} ) u |
| 20 |
C \end{equation*} |
| 21 |
|
| 22 |
C !USES: =============================================================== |
| 23 |
IMPLICIT NONE |
| 24 |
#include "SIZE.h" |
| 25 |
#include "EEPARAMS.h" |
| 26 |
#include "PARAMS.h" |
| 27 |
#include "GRID.h" |
| 28 |
#ifdef ALLOW_BOTTOMDRAG_CONTROL |
| 29 |
# include "DYNVARS.h" |
| 30 |
#endif |
| 31 |
|
| 32 |
C !INPUT PARAMETERS: =================================================== |
| 33 |
C bi,bj :: tile indices |
| 34 |
C k :: vertical level |
| 35 |
C uFld :: zonal flow |
| 36 |
C KE :: Kinetic energy |
| 37 |
C KappaRU :: vertical viscosity |
| 38 |
C myThid :: thread number |
| 39 |
INTEGER bi,bj,k |
| 40 |
_RL uFld(1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
| 41 |
_RL KE(1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
| 42 |
_RL KappaRU(1-OLx:sNx+OLx,1-OLy:sNy+OLy,Nr) |
| 43 |
INTEGER myThid |
| 44 |
|
| 45 |
C !OUTPUT PARAMETERS: ================================================== |
| 46 |
C uDragTerms :: drag term |
| 47 |
_RL uDragTerms(1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
| 48 |
|
| 49 |
C !LOCAL VARIABLES: ==================================================== |
| 50 |
C i,j :: loop indices |
| 51 |
C Kp1 :: =k+1 for k<Nr, =Nr for k>=Nr |
| 52 |
INTEGER i,j,kDown,kDownC,kBottom |
| 53 |
_RL viscFac, dragFac |
| 54 |
_RL rdrckp1, maskDown |
| 55 |
CEOP |
| 56 |
|
| 57 |
C- No-slip BCs impose a drag at bottom |
| 58 |
IF ( usingZCoords ) THEN |
| 59 |
kBottom = Nr |
| 60 |
kDown = min(k+1,kBottom) |
| 61 |
kDownC = kDown |
| 62 |
c dragFac = mass2rUnit*rhoConst |
| 63 |
c dragFac = wUnit2rVel(k+1) |
| 64 |
dragFac = 1. _d 0 |
| 65 |
ELSE |
| 66 |
kBottom = 1 |
| 67 |
kDown = max(k-1,kBottom) |
| 68 |
kDownC = k |
| 69 |
dragFac = mass2rUnit*rhoConst |
| 70 |
c dragFac = wUnit2rVel(k) |
| 71 |
ENDIF |
| 72 |
rdrckp1=recip_drC(kDownC) |
| 73 |
IF (k.EQ.kBottom) rdrckp1=recip_drF(k) |
| 74 |
viscFac=0. |
| 75 |
IF (no_slip_bottom) viscFac=1. |
| 76 |
DO j=1-Oly,sNy+Oly-1 |
| 77 |
DO i=1-Olx+1,sNx+Olx-1 |
| 78 |
maskDown=_maskW(i,j,kDown,bi,bj) |
| 79 |
IF (k.EQ.kBottom) maskDown=0. |
| 80 |
uDragTerms(i,j)= |
| 81 |
& -_recip_hFacW(i,j,k,bi,bj)*recip_drF(k) |
| 82 |
& *( |
| 83 |
& 2.*KappaRU(i,j,kDownC)*rdrckp1*viscFac |
| 84 |
#ifdef ALLOW_BOTTOMDRAG_CONTROL |
| 85 |
& + bottomdragfld(i,j,bi,bj)*dragFac |
| 86 |
#endif |
| 87 |
& + bottomDragLinear*dragFac |
| 88 |
& )*(1.-maskDown)*uFld(i,j) |
| 89 |
IF ( (KE(i,j)+KE(i-1,j)) .GT. 0. ) THEN |
| 90 |
uDragTerms(i,j)=uDragTerms(i,j) |
| 91 |
& -_recip_hFacW(i,j,k,bi,bj)*recip_drF(k) |
| 92 |
& *bottomDragQuadratic*SQRT(KE(i,j)+KE(i-1,j))*dragFac |
| 93 |
& *(1.-maskDown)*uFld(i,j) |
| 94 |
ENDIF |
| 95 |
ENDDO |
| 96 |
ENDDO |
| 97 |
|
| 98 |
#ifdef ALLOW_DIAGNOSTICS |
| 99 |
IF (useDiagnostics) THEN |
| 100 |
CALL DIAGNOSTICS_FILL(uDragTerms,'UBotDrag',k,1,2,bi,bj,myThid) |
| 101 |
ENDIF |
| 102 |
#endif /* ALLOW_DIAGNOSTICS */ |
| 103 |
|
| 104 |
RETURN |
| 105 |
END |
Parent Directory
| 
Revision Log
| 
Revision Graph