Différences

Ci-dessous, les différences entre deux révisions de la page.

--- sunfluidh:meshgen_doc [2017/12/02 15:56] – yann
+++ sunfluidh:meshgen_doc [2017/12/02 17:16] – yann
@@ Ligne 24: / Ligne 24: @@
 ==== Meshgen settings ====
-The grid parameters are set in the input data file "data_meshgen.dat".
+The grid parameters are set in the input data file "data_meshgen.dat". A simple example of a 2D grid is given just below :
+   * The cell size is variable along the I-direction.
+     * The I-line is split in two equal parts.
+     * The function "TANH_ONE_SIDE" is applied over each part, with a reverse distribution over the 2nd part. This way is useful to define a perfect symmetrical distribution in regard to the mid-plane.
+   * The grid is regular along the J-direction
 <file txt data_meshgen.dat>
@@ Ligne 58: / Ligne 64: @@
 </file>
+==== Data set description ====
+In the data file, each block of data is attributed to a direction (I,J or K).\\
+Each direction can be split in several parts (segments) on which a specific distribution law is applied in order to place the discrete nodes.\\
+Each distribution law is defined by means of namelists that are described at the end of this page. The available functions are :
+   * Regular function (Function_name= REGULAR_MESH)
+   * Hyperbolic tangent function "one side" (Function_Name= TANH_ONE_SIDE_MESH)
+   * Hyperbolic tangent function "two sides" (Function_Name= TANH_TWO_SIDES_MESH)
+   * Gauss-Lobatto distribution (Function_Name= GAUSS_LOBATTO_MESH)
+   * Geometric series "type 1" (Function_Name= GEOMETRIC_SERIE_1_MESH)
+   * Geometric series "type 2" (Function_Name= GEOMETRIC_SERIE_2_MESH)
+These functions get a specific data set :
+   * Number_of_Cells : Number of cells over the segment (for all functions).
+   * Length          : Length of the segment (for all functions).
+   * Left_Cell_Size  : Reference size of the cell placed at the left tip of the segment (for all functions except the regular function)
+   * Right_Cell_Size : Reference size of the cell placed at the right tip of the segment (for hyperbolic function "two sides" and geometric series "Type 1" only)
+   * Reverse_Ordering : Reverse the ordering of the distribution if set to .true.
+   * End_of_Block_Data : logical set to .true. to declare the end of a data structure (by default it set to .false. by the program)
+__A complete template is provided below.__
+<note important>
+For each direction, the block of data must start with the namelist \\ &METRIC_UNIT         Type_of_Metric= 0 / \\
+   * Type_of_Metric= 0 specifies a usual metric
+   * Type_of_Metric= 1 specifies an angular metric. The unit is the degree.
+The block of data must be closed with the special namelist \\ &MESH_FUNCTION_DATA End_of_Data_Block = .true./
+</note>
+==== Templates for each function ====
+<file template>
+&METRIC_UNIT Type_of_Metric= 0 /         ---> Used to define the metric unit
+&MESH_FUNCTION_DATA  Function_Name="GAUSS_LOBATTO"     Number_of_Cells= 30   Length= 1.0                                                    Reverse_Ordering= .false. /
+&MESH_FUNCTION_DATA  Function_Name="TANH_ONE_SIDE"     Number_of_Cells= 40   Length= 1.0  Left_Cell_Size= 1.0d-03                           Reverse_Ordering= .false. /
+&MESH_FUNCTION_DATA  Function_Name="GEOMETRIC_SERIE_1" Number_of_Cells= 60   Length= 1.0  Left_Cell_Size= 1.0d-02  Cell_Ratio= 1.05d-00     Reverse_Ordering= .false. /
+&MESH_FUNCTION_DATA  Function_Name="REGULAR"           Number_of_Cells= 100  Length= 1.0                                                    Reverse_Ordering= .false. /
+&MESH_FUNCTION_DATA  Function_Name="TANH_TWO_SIDES"    Number_of_Cells= 100  Length= 1.0  Left_Cell_Size= 1.0d-02  Right_Cell_Size= 1.0d-02 Reverse_Ordering= .false. /
+&MESH_FUNCTION_DATA  Function_Name="GEOMETRIC_SERIE_2" Number_of_Cells= 50   Length= 1.0  Left_Cell_Size= 1.0d-02  Right_Cell_Size= 5.0d-02 Reverse_Ordering= .false. /
+&MESH_FUNCTION_DATA  Function_Name="TANH_ONE_SIDE"     Number_of_Cells= 100  Length= 1.0  Left_Cell_Size= 1.0d-03                           Reverse_Ordering= .false. /
+&MESH_FUNCTION_DATA  End_of_Data_Block= .true.        /
+</file>
+==== Generate the grid with Meshgen ====
+After setting the data set in the file "data_meshgen.dat", run the command "meshgen.x".
+Few questions are asked :
+   * Choice of CFD code : OLORIN or SUNFLUIDH (1) CHORUS (2) ---> tape the correct option
+   * MPI domain decomposition (1) or not (0) ---> tape the correct option
+For the case of MPI domain decomposition, further information is required to perform the appropriate domain decomposition
+   * number of domain decomposition per direction
+     *  In I-direction
+     *  In J-direction
+     *  In K-direction
+The grid data are recorded in the appropriate files that depend on the code previously selected:
+    * For Chorus : maille_yyyyy.dat : data are recorded in binary format. "yyyyy" is the number of the associated subdomain.
+    * For sunfluidh : maillx_yyyyy.dat, maillx_yyyyy.dat and maillz_yyyyy.dat (one file per direction): data are recorded in ASCII format and ordered in two colums, the first one is the cell-index, the second one is the coordinate of the upper face of the cell.