The ANSYS®
input file can be created by an arbitrary FE-Preprocessor. In ANSYS®,
the CDB
file is created with the following command:
CDWRITE, Option, Fname, Ext, Dir, Fnamei, Exti, Fmat
At least one Solve-Command has always to be specified: solve
or lssolve
.
To check, if the input file is executable in batch mode, one analysis
should be performed in batch mode from the command line before starting
the complete optimization. The corresponding batch call of ANSYS®
version 14.0 on Windows is as following:
Ansys140 -b -i<input file> -o<output file> -p<productvar>
Error messages and warnings can be found in the *.err file. The input
file must be corrected if an error occurs.
As input an file for the optimization loop, TOSCA_PREP
generates an ANSYS®
CDB
file from the ANSYS®
input file. Compared to a complete ANSYS®
input file this file contains no solution strategy (/SOLU).
During the optimization procedure, the analysis results are read from
the *.rst
file.
ANSYS®
Files Generated during a Tosca Structure
Optimization
During the optimization preprocessing the ANSYS®
model will be imported to ANSYS®
and exported again to generate a standard blocked CDB
file. During this import/export step, all macros in the ANSYS®
input file will be executed in ANSYS®
and can no longer be found as macros in the input files used during the
Tosca Structure
optimization.
- The input file (
model.cdb
) is split into multiple
files during the optimization preprocessing (TOSCA_PREP
):
model_ans.cdb
input file without solution /SOLU
model_ans.head
file containing the ANSYS®
Header
model_ans.solu
file containing the ANSYS®
Solution /SOLU
. Eventually, existing load case
files *.s0X
are copied into the optimization working
directory. These remain unchanged during the optimization process.
model_ans.tosca
temporary file, which is used for
the generation of the model_ans.cdb file
- Two files are generated during the
fem_modif
call:
model_<iter>.ans
model_<iter>.cdb
. The CDB
file
is included in the ans file using a CDREAD
The model<iter>.ans
file is renamed into model.ans
before the finite element
analysis is executed. The CDB
file is not renamed -
it is referenced with the iteration extension in the ans
file.
- Two files are moved in the corresponding
SAVE
directory:
model.ans
: is copied (copy_solver_info_list
) into the
corresponding SAVE
directory and gets an iteration
counter number before the finite element analysis is executed.
model_<iter>.cdb
:
is moved (move_per_iter_xxx_list
) into the corresponding
SAVE
directory at the end of the design cycle.
- The newly created
CDB
file in blocked format is detected and analyzed
automatically by the optimization preprocessor. Thus, the FE model is
imported into Tosca Structure.
The data of the ANSYS®
model (coordinates of nodes, materials, properties, and assignment of
elements) in the CDB
file can be modified during the
optimization. The load files contain the boundary restrictions, which
provide information about boundary movements for shape optimization.
- The solve section contains the solution strategy of the original
input file, checks, and the definition of which kind of results must be
written to the
*.rst
files for shape and topology optimization,
respectively. Thus, during the ANSYS®
analysis only the results necessary for the optimization are written
to the result file.
- During the optimization the data in the
CDB
file
is modified. Afterwards the three parts are merged and a new ANSYS®
analysis is performed. The load files are not changed during the optimization.