/[MITgcm]/MITgcm/pkg/generic_advdiff/gad_dst2u1_adv_x.F
ViewVC logotype

Contents of /MITgcm/pkg/generic_advdiff/gad_dst2u1_adv_x.F

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

Revision 1.8 - (show annotations) (download)
Fri Feb 29 01:30:59 2008 UTC (16 years, 2 months ago) by mlosch
Branch: MAIN
CVS Tags: checkpoint64y, checkpoint64x, checkpoint64z, checkpoint64q, checkpoint64p, checkpoint64s, checkpoint64r, checkpoint64u, checkpoint64t, checkpoint64w, checkpoint64v, checkpoint64i, checkpoint64h, checkpoint64k, checkpoint64j, checkpoint64m, checkpoint64l, checkpoint64o, checkpoint64n, checkpoint64a, checkpoint64c, checkpoint64b, checkpoint64e, checkpoint64d, checkpoint64g, checkpoint64f, checkpoint63p, checkpoint63q, checkpoint63r, checkpoint63s, checkpoint63l, checkpoint63m, checkpoint63n, checkpoint63o, checkpoint63h, checkpoint63i, checkpoint63j, checkpoint63k, checkpoint63d, checkpoint63e, checkpoint63f, checkpoint63g, checkpoint63a, checkpoint63b, checkpoint63c, checkpoint64, checkpoint65, checkpoint60, checkpoint61, checkpoint62, checkpoint63, checkpoint66g, checkpoint66f, checkpoint66e, checkpoint66d, checkpoint66c, checkpoint66b, checkpoint66a, checkpoint66o, checkpoint66n, checkpoint66m, checkpoint66l, checkpoint66k, checkpoint66j, checkpoint66i, checkpoint66h, checkpoint65z, checkpoint65x, checkpoint65y, checkpoint65r, checkpoint65s, checkpoint65p, checkpoint65q, checkpoint65v, checkpoint65w, checkpoint65t, checkpoint65u, checkpoint65j, checkpoint65k, checkpoint65h, checkpoint65i, checkpoint65n, checkpoint65o, checkpoint65l, checkpoint65m, checkpoint65b, checkpoint65c, checkpoint65a, checkpoint65f, checkpoint65g, checkpoint65d, checkpoint65e, checkpoint59q, checkpoint59p, checkpoint59r, checkpoint59o, checkpoint62c, checkpoint62b, checkpoint62a, checkpoint62g, checkpoint62f, checkpoint62e, checkpoint62d, checkpoint62k, checkpoint62j, checkpoint62i, checkpoint62h, checkpoint62o, checkpoint62n, checkpoint62m, checkpoint62l, checkpoint62s, checkpoint62r, checkpoint62q, checkpoint62p, checkpoint62w, checkpoint62v, checkpoint62u, checkpoint62t, checkpoint62z, checkpoint62y, checkpoint62x, checkpoint61f, checkpoint61g, checkpoint61d, checkpoint61e, checkpoint61b, checkpoint61c, checkpoint61a, checkpoint61n, checkpoint61o, checkpoint61l, checkpoint61m, checkpoint61j, checkpoint61k, checkpoint61h, checkpoint61i, checkpoint61v, checkpoint61w, checkpoint61t, checkpoint61u, checkpoint61r, checkpoint61s, checkpoint61p, checkpoint61q, checkpoint61z, checkpoint61x, checkpoint61y, HEAD
Changes since 1.7: +3 -1 lines 
improve vectorizability by moving a few statements out of the main loop
1 C $Header: /u/gcmpack/MITgcm/pkg/generic_advdiff/gad_dst2u1_adv_x.F,v 1.7 2007/04/04 01:39:06 jmc Exp $
2 C $Name: $
3
4 #include "GAD_OPTIONS.h"
5
6 CBOP
7 C !ROUTINE: GAD_DST2U1_ADV_X
8
9 C !INTERFACE: ==========================================================
10 SUBROUTINE GAD_DST2U1_ADV_X(
11 I bi,bj,k, advectionScheme, calcCFL,
12 I deltaTloc, uTrans, uFld,
13 I tracer,
14 O uT,
15 I myThid )
16
17 C !DESCRIPTION:
18 C Calculates the area integrated zonal flux due to advection
19 C of a tracer using second-order Direct Space and Time (DST-2)
20 C interpolation (=Lax-Wendroff) or simple 1rst order upwind scheme.
21
22 C !USES: ===============================================================
23 IMPLICIT NONE
24 #include "SIZE.h"
25 #include "GRID.h"
26 #include "GAD.h"
27
28 C !INPUT PARAMETERS: ===================================================
29 C bi,bj :: tile indices
30 C k :: vertical level
31 C advectionScheme :: advection scheme to use: either 2nd Order DST
32 C or 1rst Order Upwind
33 C calcCFL :: =T: calculate CFL number ; =F: take uFld as CFL
34 C deltaTloc :: local time-step (s)
35 C uTrans :: zonal volume transport
36 C uFld :: zonal flow / CFL number
37 C tracer :: tracer field
38 C myThid :: thread number
39 INTEGER bi,bj,k
40 INTEGER advectionScheme
41 LOGICAL calcCFL
42 _RL deltaTloc
43 _RL uTrans(1-OLx:sNx+OLx,1-OLy:sNy+OLy)
44 _RL uFld (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
45 _RL tracer(1-OLx:sNx+OLx,1-OLy:sNy+OLy)
46 INTEGER myThid
47
48 C !OUTPUT PARAMETERS: ==================================================
49 C uT :: zonal advective flux
50 _RL uT (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
51
52 C !LOCAL VARIABLES: ====================================================
53 C i,j :: loop indices
54 C rLimit :: centered (vs upwind) fraction
55 C uCFL :: Courant-Friedrich-Levy number
56 INTEGER i,j
57 _RL uCFL, xLimit, uAbs
58 CEOP
59
60 xLimit = 0. _d 0
61 IF ( advectionScheme.EQ.ENUM_DST2 ) xLimit = 1. _d 0
62
63 DO j=1-Oly,sNy+Oly
64 uT(1-Olx,j)=0.
65 ENDDO
66 DO j=1-Oly,sNy+Oly
67 DO i=1-Olx+1,sNx+Olx
68
69 uCFL = uFld(i,j)
70 IF ( calcCFL ) uCFL = ABS( uFld(i,j)*deltaTloc
71 & *recip_dxC(i,j,bi,bj)*recip_deepFacC(k) )
72
73 c uT(i,j) =
74 c & uTrans(i,j)*(tracer(i-1,j)+tracer(i,j))*0.5 _d 0
75 c & + ( 1. _d 0 - xLimit*(1. _d 0 - uCFL) )*ABS(uTrans(i,j))
76 c & *(tracer(i-1,j)-tracer(i,j))*0.5 _d 0
77 C-- above formulation produces large truncation error when:
78 C 1rst.O upWind and u > 0 & |tracer(i-1,j)| << |tracer(i,j)|
79 C or u < 0 & |tracer(i-1,j)| >> |tracer(i,j)|
80 C-- change to a more robust expression:
81 uAbs = ABS(uTrans(i,j))
82 & *( 1. _d 0 - xLimit*(1. _d 0 - uCFL) )
83 uT(i,j) = ( uTrans(i,j)+uAbs )* 0.5 _d 0 * tracer(i-1,j)
84 & + ( uTrans(i,j)-uAbs )* 0.5 _d 0 * tracer(i,j)
85 ENDDO
86 ENDDO
87
88 RETURN
89 END
  ViewVC Help
Powered by ViewVC 1.1.22