cfpart is used to partition a single-zone unstructured grid into multiple zones for parallel processing. Boundary conditions and surfaces defined in the original file are preserved in the partitioned file. Additional "crinkly" surfaces will appear at the boundaries between the newly-created zones, with negative surface ID numbers. The appropriate coupled boundary conditions are automatically set for these zonal boundaries.
Mapping data is written into the partitioned .cgd file, that maps the split grid to the original single-zone grid. This data is used by the cfspart utility when re-partitioning multi-zone common flow (.cfl) and boundary data (.tda) files into a different number of zones.
Input to cfpart is specified in a keyword input file, with the three-letter extension .inp. Lines in the input file starting with a "/" are comments. The following keywords and values may be specified.
| CHECK | Checks the input file for errors without performing any
operations.
| ||
| FILE file_in.cgd | The input common grid (.cgd) file (80 characters max),
containing the unstructured grid to be partitioned.
| ||
| OUTPUT file_out.cgd | The output .cgd file (80 characters max), containing the
partitioned grid.
| ||
| NCPUS value | The number of zones into which the grid is to be partitioned.
Each zone will have (roughly) the same number of cells.
Thus for maximum efficiency, the number of zones should match
the number of available worker CPUs.
| ||
| CREATELINES | Turns on the global line calculation, required for the line
Gauss-Seidel implicit solver (i.e., the LINE option
in the Wind-US
IMPLICIT
keyword).
This is especially important for viscous calculations.
| ||
| MINLINE nmin | The minimum length of a line.
The default value is 20.
| ||
| MAXLINE nmax | The maximum length of a line.
The default value is 1000.
This value is not currently used.
| ||
| ANGLELIMIT angle | The maximum turning angle allowed when creating lines, in degrees.
The default value is 85.
| ||
| ASPECTRATIOMIN ar | The minimum aspect ratio allowed for cells to be eligible for
inclusion in lines.
The default value is 1.6.
| ||
| MINFACESPERCELLINLINE nfaces | This keyword controls which cell types are included when
creating lines.
Set nfaces = 4 to include all cell types, 5 to only
include non-tetrahedral cells, and 6 to only include hexahedral
cells.
The default value is 4.
| ||
| LINEMODE mode | This specifies the approach used to determine lines.
Setting mode = 0 corresponds to the basic way of
evaluating the transformation matrix to a canonical element;
set mode = 1 to use projected face areas to determine an
aspect ratio.
The default value is 0.
| ||
| WRITELINES | If this keyword is specified, the lines will be written to a
file named lines.fvp. Fieldview can read and display
these lines as particle paths.
| ||
| LOWMEM | If this keyword is specified, data required by cfpart
will be written to disk instead of being kept in memory.
This will increase the CPU time required, and should only be
used on systems with insufficient memory.
| ||
| GROUPFILENAME filename \ [MODE {APPEND|REPLACE}] | Read surface group definitions from a text file and include
these group definitions in the output grid (.cgd) file.
Mode APPEND will append to the list of existing groups
read from the input grid (.cgd) file and give an error if
the specified groupname already exists.
Mode REPLACE will ignore any existing groups from the
input grid file.
The format of the group definition file is as follows:
BEGIN [GROUP] groupname
{ [SURFACE U surfID [ZONE zone]] | \
[GROUP groupname] }
...(repeat as necessary for additional surfaces)
END [GROUP]
...(repeat as necessary for additional groups)
|
Example
The following example shows how cfpart may be used to partition a single-zone grid into five zones, suitable for parallel processing on five CPUs. The keyword input file, named M2129_cfpart.inp is:
/ Input single-zone grid / FILE M2129_1zone.cgd / / Output grid / OUTPUT M2129_5zone.cgd / / Split for 5 CPUs / NCPUS 5 / / Create lines for line Gauss-Seidel solver / CREATELINES
The terminal session is shown below. Lines in a slanted font are typed by the user.
% cfpart
***** cfpart *****
Select the desired version from the following list.
0) END
1) cfpart
Single program automatically selected.
Omit the .inp extension!
Enter cfpart INPUT FILE ............. (<CR>=cfpart.inp) : M2129_cfpart
CFPART - Version 1.2 (last changed 2008/09/05 19:58:42)
****************************************************************************
* Warning: This software contains technical data whose export is *
* restricted by the Arms Export Control Act (Title 22, U.S.C., Sec 2751, *
* et seq.) or Executive Order 12470. Violation of these export-control *
* laws is subject to severe criminal penalties. Dissemination of this *
* software is controlled under DoD Directive 5230.25 and AFI 61-204. *
****************************************************************************
beginning of us_main
Step Read grid
Time= 0.2639600 0.2639600
Step Face Connectivity
Time= 0.8398730 1.103833
Step Partitoning
*** Line statistics report ***
num lines = 16695
zero length lines = 0
minimum line length = 20
maximum line length = 149
average line length = 26.3946091644205
******************************
Time= 1.734736 2.838569
Step Global-Local cell function
Time= 3.9999485E-03 2.842569
Step Surface and face pointers 1
Time= 2.6996136E-02 2.869565
Step Volume data 1
Time= 2.3995876E-02 2.893561
Step CGD write 1
Time= 3.6993980E-02 2.930555
Step Surface and face pointers 2
Time= 2.0997047E-02 2.951552
Step Volume data 2
Time= 2.5995970E-02 2.977548
Step CGD write 2
Time= 3.8993120E-02 3.016541
Step Surface and face pointers 3
Time= 2.1996975E-02 3.038538
Step Volume data 3
Time= 2.7996063E-02 3.066534
Step CGD write 3
Time= 3.8993835E-02 3.105528
Step Surface and face pointers 4
Time= 2.1996975E-02 3.127525
Step Volume data 4
Time= 2.4996042E-02 3.152521
Step CGD write 4
Time= 3.8994074E-02 3.191515
Step Surface and face pointers 5
Time= 1.8996954E-02 3.210512
Step Volume data 5
Time= 2.4996996E-02 3.235509
Step CGD write 5
Time= 3.6995173E-02 3.273503
Total time 3.278502
end of us_main
in Linelet- Remapping cells
Total time 3.326493
end of cfpart_main
Last updated 15 Nov 2011