| [1212] | 1 | MODULE tridia_solver |
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| 2 | |
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| 3 | !--------------------------------------------------------------------------------! |
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| 4 | ! This file is part of PALM. |
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| 5 | ! |
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| 6 | ! PALM is free software: you can redistribute it and/or modify it under the terms |
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| 7 | ! of the GNU General Public License as published by the Free Software Foundation, |
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| 8 | ! either version 3 of the License, or (at your option) any later version. |
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| 9 | ! |
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| 10 | ! PALM is distributed in the hope that it will be useful, but WITHOUT ANY |
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| 11 | ! WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR |
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| 12 | ! A PARTICULAR PURPOSE. See the GNU General Public License for more details. |
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| 13 | ! |
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| 14 | ! You should have received a copy of the GNU General Public License along with |
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| 15 | ! PALM. If not, see <http://www.gnu.org/licenses/>. |
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| 16 | ! |
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| 17 | ! Copyright 1997-2012 Leibniz University Hannover |
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| 18 | !--------------------------------------------------------------------------------! |
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| 19 | ! |
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| 20 | ! Current revisions: |
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| 21 | ! ------------------ |
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| [1213] | 22 | ! |
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| 23 | ! |
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| 24 | ! Former revisions: |
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| 25 | ! ----------------- |
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| 26 | ! $Id: tridia_solver.f90 1213 2013-08-15 09:03:50Z kanani $ |
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| 27 | ! |
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| 28 | ! 1212 2013-08-15 08:46:27Z raasch |
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| [1212] | 29 | ! Initial revision. |
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| 30 | ! Routines have been moved to seperate module from former file poisfft to here. |
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| 31 | ! The tridiagonal matrix coefficients of array tri are calculated only once at |
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| 32 | ! the beginning, i.e. routine split is called within tridia_init. |
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| 33 | ! |
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| 34 | ! |
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| 35 | ! Description: |
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| 36 | ! ------------ |
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| 37 | ! solves the linear system of equations: |
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| 38 | ! |
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| 39 | ! -(4 pi^2(i^2/(dx^2*nnx^2)+j^2/(dy^2*nny^2))+ |
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| 40 | ! 1/(dzu(k)*dzw(k))+1/(dzu(k-1)*dzw(k)))*p(i,j,k)+ |
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| 41 | ! 1/(dzu(k)*dzw(k))*p(i,j,k+1)+1/(dzu(k-1)*dzw(k))*p(i,j,k-1)=d(i,j,k) |
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| 42 | ! |
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| 43 | ! by using the Thomas algorithm |
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| 44 | !------------------------------------------------------------------------------! |
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| 45 | |
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| 46 | USE indices |
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| 47 | USE transpose_indices |
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| 48 | |
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| 49 | IMPLICIT NONE |
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| 50 | |
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| 51 | REAL, DIMENSION(:,:), ALLOCATABLE :: ddzuw |
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| 52 | |
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| 53 | PRIVATE |
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| 54 | |
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| 55 | INTERFACE tridia_substi |
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| 56 | MODULE PROCEDURE tridia_substi |
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| 57 | END INTERFACE tridia_substi |
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| 58 | |
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| 59 | PUBLIC tridia_substi, tridia_init, tridia_1dd |
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| 60 | |
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| 61 | CONTAINS |
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| 62 | |
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| 63 | |
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| 64 | SUBROUTINE tridia_init |
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| 65 | |
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| 66 | USE arrays_3d, ONLY: ddzu_pres, ddzw |
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| 67 | |
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| 68 | IMPLICIT NONE |
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| 69 | |
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| 70 | INTEGER :: k |
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| 71 | |
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| 72 | ALLOCATE( ddzuw(0:nz-1,3) ) |
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| 73 | |
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| 74 | DO k = 0, nz-1 |
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| 75 | ddzuw(k,1) = ddzu_pres(k+1) * ddzw(k+1) |
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| 76 | ddzuw(k,2) = ddzu_pres(k+2) * ddzw(k+1) |
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| 77 | ddzuw(k,3) = -1.0 * & |
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| 78 | ( ddzu_pres(k+2) * ddzw(k+1) + ddzu_pres(k+1) * ddzw(k+1) ) |
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| 79 | ENDDO |
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| 80 | ! |
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| 81 | !-- Calculate constant coefficients of the tridiagonal matrix |
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| 82 | #if ! defined ( __check ) |
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| 83 | CALL maketri |
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| 84 | CALL split |
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| 85 | #endif |
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| 86 | |
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| 87 | END SUBROUTINE tridia_init |
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| 88 | |
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| 89 | |
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| 90 | SUBROUTINE maketri |
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| 91 | |
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| 92 | !------------------------------------------------------------------------------! |
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| 93 | ! Computes the i- and j-dependent component of the matrix |
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| 94 | !------------------------------------------------------------------------------! |
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| 95 | |
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| 96 | USE arrays_3d, ONLY: tric |
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| 97 | USE constants |
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| 98 | USE control_parameters |
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| 99 | USE grid_variables |
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| 100 | |
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| 101 | IMPLICIT NONE |
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| 102 | |
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| 103 | INTEGER :: i, j, k, nnxh, nnyh |
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| 104 | |
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| 105 | !$acc declare create( ll ) |
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| 106 | REAL :: ll(nxl_z:nxr_z,nys_z:nyn_z) |
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| 107 | |
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| 108 | |
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| 109 | nnxh = ( nx + 1 ) / 2 |
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| 110 | nnyh = ( ny + 1 ) / 2 |
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| 111 | |
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| 112 | ! |
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| 113 | !-- Provide the constant coefficients of the tridiagonal matrix for solution |
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| 114 | !-- of the Poisson equation in Fourier space. |
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| 115 | !-- The coefficients are computed following the method of |
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| 116 | !-- Schmidt et al. (DFVLR-Mitteilung 84-15), which departs from Stephan |
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| 117 | !-- Siano's original version by discretizing the Poisson equation, |
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| 118 | !-- before it is Fourier-transformed. |
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| 119 | |
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| 120 | !$acc kernels present( tric ) |
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| 121 | !$acc loop vector( 32 ) |
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| 122 | DO j = nys_z, nyn_z |
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| 123 | DO i = nxl_z, nxr_z |
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| 124 | IF ( j >= 0 .AND. j <= nnyh ) THEN |
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| 125 | IF ( i >= 0 .AND. i <= nnxh ) THEN |
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| 126 | ll(i,j) = 2.0 * ( 1.0 - COS( ( 2.0 * pi * i ) / & |
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| 127 | REAL( nx+1 ) ) ) / ( dx * dx ) + & |
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| 128 | 2.0 * ( 1.0 - COS( ( 2.0 * pi * j ) / & |
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| 129 | REAL( ny+1 ) ) ) / ( dy * dy ) |
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| 130 | ELSE |
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| 131 | ll(i,j) = 2.0 * ( 1.0 - COS( ( 2.0 * pi * ( nx+1-i ) ) / & |
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| 132 | REAL( nx+1 ) ) ) / ( dx * dx ) + & |
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| 133 | 2.0 * ( 1.0 - COS( ( 2.0 * pi * j ) / & |
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| 134 | REAL( ny+1 ) ) ) / ( dy * dy ) |
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| 135 | ENDIF |
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| 136 | ELSE |
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| 137 | IF ( i >= 0 .AND. i <= nnxh ) THEN |
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| 138 | ll(i,j) = 2.0 * ( 1.0 - COS( ( 2.0 * pi * i ) / & |
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| 139 | REAL( nx+1 ) ) ) / ( dx * dx ) + & |
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| 140 | 2.0 * ( 1.0 - COS( ( 2.0 * pi * ( ny+1-j ) ) / & |
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| 141 | REAL( ny+1 ) ) ) / ( dy * dy ) |
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| 142 | ELSE |
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| 143 | ll(i,j) = 2.0 * ( 1.0 - COS( ( 2.0 * pi * ( nx+1-i ) ) / & |
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| 144 | REAL( nx+1 ) ) ) / ( dx * dx ) + & |
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| 145 | 2.0 * ( 1.0 - COS( ( 2.0 * pi * ( ny+1-j ) ) / & |
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| 146 | REAL( ny+1 ) ) ) / ( dy * dy ) |
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| 147 | ENDIF |
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| 148 | ENDIF |
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| 149 | ENDDO |
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| 150 | ENDDO |
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| 151 | |
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| 152 | !$acc loop |
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| 153 | DO k = 0, nz-1 |
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| 154 | DO j = nys_z, nyn_z |
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| 155 | !$acc loop vector( 32 ) |
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| 156 | DO i = nxl_z, nxr_z |
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| 157 | tric(i,j,k) = ddzuw(k,3) - ll(i,j) |
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| 158 | ENDDO |
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| 159 | ENDDO |
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| 160 | ENDDO |
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| 161 | !$acc end kernels |
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| 162 | |
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| 163 | IF ( ibc_p_b == 1 ) THEN |
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| 164 | !$acc kernels present( tric ) |
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| 165 | !$acc loop |
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| 166 | DO j = nys_z, nyn_z |
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| 167 | DO i = nxl_z, nxr_z |
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| 168 | tric(i,j,0) = tric(i,j,0) + ddzuw(0,1) |
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| 169 | ENDDO |
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| 170 | ENDDO |
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| 171 | !$acc end kernels |
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| 172 | ENDIF |
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| 173 | IF ( ibc_p_t == 1 ) THEN |
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| 174 | !$acc kernels present( tric ) |
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| 175 | !$acc loop |
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| 176 | DO j = nys_z, nyn_z |
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| 177 | DO i = nxl_z, nxr_z |
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| 178 | tric(i,j,nz-1) = tric(i,j,nz-1) + ddzuw(nz-1,2) |
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| 179 | ENDDO |
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| 180 | ENDDO |
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| 181 | !$acc end kernels |
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| 182 | ENDIF |
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| 183 | |
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| 184 | END SUBROUTINE maketri |
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| 185 | |
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| 186 | |
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| 187 | SUBROUTINE tridia_substi( ar ) |
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| 188 | |
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| 189 | !------------------------------------------------------------------------------! |
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| 190 | ! Substitution (Forward and Backward) (Thomas algorithm) |
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| 191 | !------------------------------------------------------------------------------! |
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| 192 | |
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| 193 | USE arrays_3d, ONLY: tri |
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| 194 | USE control_parameters |
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| 195 | |
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| 196 | IMPLICIT NONE |
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| 197 | |
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| 198 | INTEGER :: i, j, k |
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| 199 | |
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| 200 | REAL :: ar(nxl_z:nxr_z,nys_z:nyn_z,1:nz) |
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| 201 | |
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| 202 | !$acc declare create( ar1 ) |
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| 203 | REAL, DIMENSION(nxl_z:nxr_z,nys_z:nyn_z,0:nz-1) :: ar1 |
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| 204 | |
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| 205 | ! |
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| 206 | !-- Forward substitution |
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| 207 | DO k = 0, nz - 1 |
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| 208 | !$acc kernels present( ar, tri ) |
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| 209 | !$acc loop |
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| 210 | DO j = nys_z, nyn_z |
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| 211 | DO i = nxl_z, nxr_z |
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| 212 | |
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| 213 | IF ( k == 0 ) THEN |
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| 214 | ar1(i,j,k) = ar(i,j,k+1) |
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| 215 | ELSE |
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| 216 | ar1(i,j,k) = ar(i,j,k+1) - tri(i,j,k,2) * ar1(i,j,k-1) |
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| 217 | ENDIF |
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| 218 | |
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| 219 | ENDDO |
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| 220 | ENDDO |
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| 221 | !$acc end kernels |
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| 222 | ENDDO |
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| 223 | |
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| 224 | ! |
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| 225 | !-- Backward substitution |
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| 226 | !-- Note, the 1.0E-20 in the denominator is due to avoid divisions |
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| 227 | !-- by zero appearing if the pressure bc is set to neumann at the top of |
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| 228 | !-- the model domain. |
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| 229 | DO k = nz-1, 0, -1 |
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| 230 | !$acc kernels present( ar, tri ) |
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| 231 | !$acc loop |
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| 232 | DO j = nys_z, nyn_z |
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| 233 | DO i = nxl_z, nxr_z |
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| 234 | |
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| 235 | IF ( k == nz-1 ) THEN |
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| 236 | ar(i,j,k+1) = ar1(i,j,k) / ( tri(i,j,k,1) + 1.0E-20 ) |
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| 237 | ELSE |
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| 238 | ar(i,j,k+1) = ( ar1(i,j,k) - ddzuw(k,2) * ar(i,j,k+2) ) & |
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| 239 | / tri(i,j,k,1) |
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| 240 | ENDIF |
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| 241 | ENDDO |
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| 242 | ENDDO |
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| 243 | !$acc end kernels |
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| 244 | ENDDO |
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| 245 | |
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| 246 | ! |
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| 247 | !-- Indices i=0, j=0 correspond to horizontally averaged pressure. |
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| 248 | !-- The respective values of ar should be zero at all k-levels if |
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| 249 | !-- acceleration of horizontally averaged vertical velocity is zero. |
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| 250 | IF ( ibc_p_b == 1 .AND. ibc_p_t == 1 ) THEN |
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| 251 | IF ( nys_z == 0 .AND. nxl_z == 0 ) THEN |
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| 252 | !$acc kernels loop present( ar ) |
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| 253 | DO k = 1, nz |
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| 254 | ar(nxl_z,nys_z,k) = 0.0 |
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| 255 | ENDDO |
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| 256 | ENDIF |
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| 257 | ENDIF |
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| 258 | |
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| 259 | END SUBROUTINE tridia_substi |
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| 260 | |
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| 261 | |
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| 262 | SUBROUTINE split |
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| 263 | |
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| 264 | !------------------------------------------------------------------------------! |
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| 265 | ! Splitting of the tridiagonal matrix (Thomas algorithm) |
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| 266 | !------------------------------------------------------------------------------! |
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| 267 | |
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| 268 | USE arrays_3d, ONLY: tri, tric |
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| 269 | |
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| 270 | IMPLICIT NONE |
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| 271 | |
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| 272 | INTEGER :: i, j, k |
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| 273 | |
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| 274 | ! |
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| 275 | !-- Splitting |
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| 276 | !$acc kernels present( tri, tric ) |
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| 277 | !$acc loop |
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| 278 | DO j = nys_z, nyn_z |
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| 279 | !$acc loop vector( 32 ) |
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| 280 | DO i = nxl_z, nxr_z |
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| 281 | tri(i,j,0,1) = tric(i,j,0) |
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| 282 | ENDDO |
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| 283 | ENDDO |
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| 284 | !$acc end kernels |
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| 285 | |
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| 286 | DO k = 1, nz-1 |
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| 287 | !$acc kernels present( tri, tric ) |
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| 288 | !$acc loop |
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| 289 | DO j = nys_z, nyn_z |
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| 290 | !$acc loop vector( 32 ) |
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| 291 | DO i = nxl_z, nxr_z |
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| 292 | tri(i,j,k,2) = ddzuw(k,1) / tri(i,j,k-1,1) |
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| 293 | tri(i,j,k,1) = tric(i,j,k) - ddzuw(k-1,2) * tri(i,j,k,2) |
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| 294 | ENDDO |
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| 295 | ENDDO |
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| 296 | !$acc end kernels |
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| 297 | ENDDO |
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| 298 | |
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| 299 | END SUBROUTINE split |
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| 300 | |
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| 301 | |
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| 302 | SUBROUTINE tridia_1dd( ddx2, ddy2, nx, ny, j, ar, tri ) |
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| 303 | |
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| 304 | !------------------------------------------------------------------------------! |
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| 305 | ! Solves the linear system of equations for a 1d-decomposition along x (see |
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| 306 | ! tridia) |
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| 307 | ! |
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| 308 | ! Attention: when using the intel compilers older than 12.0, array tri must |
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| 309 | ! be passed as an argument to the contained subroutines. Otherwise |
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| 310 | ! addres faults will occur. This feature can be activated with |
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| 311 | ! cpp-switch __intel11 |
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| 312 | ! On NEC, tri should not be passed (except for routine substi_1dd) |
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| 313 | ! because this causes very bad performance. |
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| 314 | !------------------------------------------------------------------------------! |
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| 315 | |
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| 316 | USE arrays_3d |
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| 317 | USE control_parameters |
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| 318 | |
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| 319 | USE pegrid |
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| 320 | |
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| 321 | IMPLICIT NONE |
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| 322 | |
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| 323 | INTEGER :: i, j, k, nnyh, nx, ny, omp_get_thread_num, tn |
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| 324 | |
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| 325 | REAL :: ddx2, ddy2 |
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| 326 | |
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| 327 | REAL, DIMENSION(0:nx,1:nz) :: ar |
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| 328 | REAL, DIMENSION(5,0:nx,0:nz-1) :: tri |
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| 329 | |
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| 330 | |
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| 331 | nnyh = ( ny + 1 ) / 2 |
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| 332 | |
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| 333 | ! |
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| 334 | !-- Define constant elements of the tridiagonal matrix. |
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| 335 | !-- The compiler on SX6 does loop exchange. If 0:nx is a high power of 2, |
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| 336 | !-- the exchanged loops create bank conflicts. The following directive |
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| 337 | !-- prohibits loop exchange and the loops perform much better. |
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| 338 | ! tn = omp_get_thread_num() |
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| 339 | ! WRITE( 120+tn, * ) '+++ id=',myid,' nx=',nx,' thread=', omp_get_thread_num() |
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| 340 | ! CALL local_flush( 120+tn ) |
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| 341 | !CDIR NOLOOPCHG |
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| 342 | DO k = 0, nz-1 |
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| 343 | DO i = 0,nx |
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| 344 | tri(2,i,k) = ddzu_pres(k+1) * ddzw(k+1) |
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| 345 | tri(3,i,k) = ddzu_pres(k+2) * ddzw(k+1) |
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| 346 | ENDDO |
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| 347 | ENDDO |
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| 348 | ! WRITE( 120+tn, * ) '+++ id=',myid,' end of first tridia loop thread=', omp_get_thread_num() |
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| 349 | ! CALL local_flush( 120+tn ) |
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| 350 | |
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| 351 | IF ( j <= nnyh ) THEN |
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| 352 | #if defined( __intel11 ) |
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| 353 | CALL maketri_1dd( j, tri ) |
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| 354 | #else |
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| 355 | CALL maketri_1dd( j ) |
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| 356 | #endif |
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| 357 | ELSE |
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| 358 | #if defined( __intel11 ) |
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| 359 | CALL maketri_1dd( ny+1-j, tri ) |
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| 360 | #else |
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| 361 | CALL maketri_1dd( ny+1-j ) |
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| 362 | #endif |
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| 363 | ENDIF |
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| 364 | #if defined( __intel11 ) |
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| 365 | CALL split_1dd( tri ) |
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| 366 | #else |
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| 367 | CALL split_1dd |
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| 368 | #endif |
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| 369 | CALL substi_1dd( ar, tri ) |
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| 370 | |
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| 371 | CONTAINS |
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| 372 | |
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| 373 | #if defined( __intel11 ) |
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| 374 | SUBROUTINE maketri_1dd( j, tri ) |
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| 375 | #else |
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| 376 | SUBROUTINE maketri_1dd( j ) |
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| 377 | #endif |
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| 378 | |
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| 379 | !------------------------------------------------------------------------------! |
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| 380 | ! computes the i- and j-dependent component of the matrix |
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| 381 | !------------------------------------------------------------------------------! |
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| 382 | |
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| 383 | USE constants |
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| 384 | |
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| 385 | IMPLICIT NONE |
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| 386 | |
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| 387 | INTEGER :: i, j, k, nnxh |
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| 388 | REAL :: a, c |
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| 389 | |
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| 390 | REAL, DIMENSION(0:nx) :: l |
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| 391 | |
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| 392 | #if defined( __intel11 ) |
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| 393 | REAL, DIMENSION(5,0:nx,0:nz-1) :: tri |
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| 394 | #endif |
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| 395 | |
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| 396 | |
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| 397 | nnxh = ( nx + 1 ) / 2 |
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| 398 | ! |
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| 399 | !-- Provide the tridiagonal matrix for solution of the Poisson equation in |
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| 400 | !-- Fourier space. The coefficients are computed following the method of |
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| 401 | !-- Schmidt et al. (DFVLR-Mitteilung 84-15), which departs from Stephan |
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| 402 | !-- Siano's original version by discretizing the Poisson equation, |
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| 403 | !-- before it is Fourier-transformed |
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| 404 | DO i = 0, nx |
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| 405 | IF ( i >= 0 .AND. i <= nnxh ) THEN |
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| 406 | l(i) = 2.0 * ( 1.0 - COS( ( 2.0 * pi * i ) / & |
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| 407 | REAL( nx+1 ) ) ) * ddx2 + & |
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| 408 | 2.0 * ( 1.0 - COS( ( 2.0 * pi * j ) / & |
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| 409 | REAL( ny+1 ) ) ) * ddy2 |
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| 410 | ELSE |
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| 411 | l(i) = 2.0 * ( 1.0 - COS( ( 2.0 * pi * ( nx+1-i ) ) / & |
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| 412 | REAL( nx+1 ) ) ) * ddx2 + & |
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| 413 | 2.0 * ( 1.0 - COS( ( 2.0 * pi * j ) / & |
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| 414 | REAL( ny+1 ) ) ) * ddy2 |
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| 415 | ENDIF |
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| 416 | ENDDO |
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| 417 | |
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| 418 | DO k = 0, nz-1 |
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| 419 | DO i = 0, nx |
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| 420 | a = -1.0 * ddzu_pres(k+2) * ddzw(k+1) |
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| 421 | c = -1.0 * ddzu_pres(k+1) * ddzw(k+1) |
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| 422 | tri(1,i,k) = a + c - l(i) |
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| 423 | ENDDO |
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| 424 | ENDDO |
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| 425 | IF ( ibc_p_b == 1 ) THEN |
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| 426 | DO i = 0, nx |
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| 427 | tri(1,i,0) = tri(1,i,0) + tri(2,i,0) |
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| 428 | ENDDO |
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| 429 | ENDIF |
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| 430 | IF ( ibc_p_t == 1 ) THEN |
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| 431 | DO i = 0, nx |
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| 432 | tri(1,i,nz-1) = tri(1,i,nz-1) + tri(3,i,nz-1) |
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| 433 | ENDDO |
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| 434 | ENDIF |
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| 435 | |
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| 436 | END SUBROUTINE maketri_1dd |
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| 437 | |
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| 438 | |
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| 439 | #if defined( __intel11 ) |
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| 440 | SUBROUTINE split_1dd( tri ) |
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| 441 | #else |
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| 442 | SUBROUTINE split_1dd |
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| 443 | #endif |
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| 444 | |
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| 445 | !------------------------------------------------------------------------------! |
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| 446 | ! Splitting of the tridiagonal matrix (Thomas algorithm) |
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| 447 | !------------------------------------------------------------------------------! |
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| 448 | |
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| 449 | IMPLICIT NONE |
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| 450 | |
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| 451 | INTEGER :: i, k |
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| 452 | |
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| 453 | #if defined( __intel11 ) |
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| 454 | REAL, DIMENSION(5,0:nx,0:nz-1) :: tri |
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| 455 | #endif |
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| 456 | |
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| 457 | |
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| 458 | ! |
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| 459 | !-- Splitting |
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| 460 | DO i = 0, nx |
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| 461 | tri(4,i,0) = tri(1,i,0) |
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| 462 | ENDDO |
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| 463 | DO k = 1, nz-1 |
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| 464 | DO i = 0, nx |
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| 465 | tri(5,i,k) = tri(2,i,k) / tri(4,i,k-1) |
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| 466 | tri(4,i,k) = tri(1,i,k) - tri(3,i,k-1) * tri(5,i,k) |
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| 467 | ENDDO |
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| 468 | ENDDO |
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| 469 | |
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| 470 | END SUBROUTINE split_1dd |
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| 471 | |
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| 472 | |
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| 473 | SUBROUTINE substi_1dd( ar, tri ) |
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| 474 | |
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| 475 | !------------------------------------------------------------------------------! |
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| 476 | ! Substitution (Forward and Backward) (Thomas algorithm) |
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| 477 | !------------------------------------------------------------------------------! |
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| 478 | |
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| 479 | IMPLICIT NONE |
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| 480 | |
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| 481 | INTEGER :: i, k |
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| 482 | |
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| 483 | REAL, DIMENSION(0:nx,nz) :: ar |
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| 484 | REAL, DIMENSION(0:nx,0:nz-1) :: ar1 |
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| 485 | REAL, DIMENSION(5,0:nx,0:nz-1) :: tri |
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| 486 | |
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| 487 | ! |
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| 488 | !-- Forward substitution |
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| 489 | DO i = 0, nx |
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| 490 | ar1(i,0) = ar(i,1) |
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| 491 | ENDDO |
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| 492 | DO k = 1, nz-1 |
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| 493 | DO i = 0, nx |
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| 494 | ar1(i,k) = ar(i,k+1) - tri(5,i,k) * ar1(i,k-1) |
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| 495 | ENDDO |
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| 496 | ENDDO |
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| 497 | |
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| 498 | ! |
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| 499 | !-- Backward substitution |
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| 500 | !-- Note, the add of 1.0E-20 in the denominator is due to avoid divisions |
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| 501 | !-- by zero appearing if the pressure bc is set to neumann at the top of |
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| 502 | !-- the model domain. |
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| 503 | DO i = 0, nx |
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| 504 | ar(i,nz) = ar1(i,nz-1) / ( tri(4,i,nz-1) + 1.0E-20 ) |
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| 505 | ENDDO |
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| 506 | DO k = nz-2, 0, -1 |
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| 507 | DO i = 0, nx |
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| 508 | ar(i,k+1) = ( ar1(i,k) - tri(3,i,k) * ar(i,k+2) ) & |
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| 509 | / tri(4,i,k) |
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| 510 | ENDDO |
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| 511 | ENDDO |
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| 512 | |
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| 513 | ! |
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| 514 | !-- Indices i=0, j=0 correspond to horizontally averaged pressure. |
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| 515 | !-- The respective values of ar should be zero at all k-levels if |
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| 516 | !-- acceleration of horizontally averaged vertical velocity is zero. |
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| 517 | IF ( ibc_p_b == 1 .AND. ibc_p_t == 1 ) THEN |
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| 518 | IF ( j == 0 ) THEN |
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| 519 | DO k = 1, nz |
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| 520 | ar(0,k) = 0.0 |
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| 521 | ENDDO |
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| 522 | ENDIF |
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| 523 | ENDIF |
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| 524 | |
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| 525 | END SUBROUTINE substi_1dd |
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| 526 | |
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| 527 | END SUBROUTINE tridia_1dd |
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| 528 | |
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| 529 | |
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| 530 | END MODULE tridia_solver |
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