Changeset 778 for palm/trunk/SOURCE/init_pegrid.f90

Timestamp:

Nov 7, 2011 2:18:25 PM (12 years ago)

Author:

fricke

Message:

Modifications of the multigrid pressure solver

File:

• palm/trunk/SOURCE/init_pegrid.f90 (modified) (8 diffs)

palm/trunk/SOURCE/init_pegrid.f90

@@ -4 +4 @@
 ! Current revisions:
 ! -----------------
-! 
+! Calculation of subdomain_size now considers the number of ghost points.
+! Further coarsening on PE0 is now possible for multigrid solver if the 
+! collected field has more grid points than the subdomain of an PE.
 !
 ! ATTENTION: nnz_x undefined problem still has to be solved!!!!!!!!
@@ -114 +116 @@
     IMPLICIT NONE
 
-    INTEGER ::  gathered_size, i, id_inflow_l, id_recycling_l, ind(5), j, k, &
+    INTEGER ::  i, id_inflow_l, id_recycling_l, ind(5), j, k,                &
                 maximum_grid_level_l, mg_switch_to_pe0_level_l, mg_levels_x, &
                 mg_levels_y, mg_levels_z, nnx_y, nnx_z, nny_x, nny_z, nnz_x, &
                 nnz_y, numproc_sqr, nx_total, nxl_l, nxr_l, nyn_l, nys_l,    &
-                nzb_l, nzt_l, omp_get_num_threads, subdomain_size
+                nzb_l, nzt_l, omp_get_num_threads
 
     INTEGER, DIMENSION(:), ALLOCATABLE ::  ind_all, nxlf, nxrf, nynf, nysf
@@ -879 +881 @@
 
           ELSE
-
              mg_switch_to_pe0_level_l = 0
              maximum_grid_level_l = maximum_grid_level
@@ -889 +890 @@
 !--       by user
           IF ( mg_switch_to_pe0_level == 0 )  THEN
-
              IF ( mg_switch_to_pe0_level_l /= 0 )  THEN
                 mg_switch_to_pe0_level = mg_switch_to_pe0_level_l
@@ -922 +922 @@
 
        grid_level_count = 0
+
        nxl_l = nxl; nxr_l = nxr; nys_l = nys; nyn_l = nyn; nzt_l = nzt
 
@@ -952 +953 @@
 !--          The size of this gathered array must not be larger than the
 !--          array tend, which is used in the multigrid scheme as a temporary
-!--          array
-             subdomain_size = ( nxr - nxl + 3 )     * ( nyn - nys + 3 )     * &
-                              ( nzt - nzb + 2 )
+!--          array. Therefore the subdomain size of an PE is calculated and 
+!--          the size of the gathered grid. These values are used in  
+!--          routines pres and poismg
+             subdomain_size = ( nxr - nxl + 2 * nbgp + 1 ) * &
+                              ( nyn - nys + 2 * nbgp + 1 ) * ( nzt - nzb + 2 )
              gathered_size  = ( nxr_l - nxl_l + 3 ) * ( nyn_l - nys_l + 3 ) * &
                               ( nzt_l - nzb + 2 )
 
-             IF ( gathered_size > subdomain_size )  THEN
-                message_string = 'not enough memory for storing ' // &
-                                 'gathered multigrid data on PE0'
-                CALL message( 'init_pegrid', 'PA0236', 1, 2, 0, 6, 0 )
-             ENDIF
 #else
              message_string = 'multigrid gather/scatter impossible ' // &
@@ -981 +979 @@
           nyn_l = nyn_l / 2 
           nzt_l = nzt_l / 2 
+
        ENDDO
 
@@ -987 +986 @@
        maximum_grid_level = 0
 
+    ENDIF
+
+!-- Temporary problem: In the moment the summation to calculate maxerror
+!-- in routine poismg crashes the program if the first coarsement is on PE0.
+!-- Further work required.
+    IF ( maximum_grid_level == mg_switch_to_pe0_level )  THEN
+       message_string = 'At least one coarser grid must be calculated ' // &
+                        'on the subdomain of each PE'
+       CALL message( 'poismg', 'PA0236', 1, 2, 0, 6, 0 )
     ENDIF