The following describes the general procedure for the definition of
an optimization task. These procedures are supported by the command tree in
Tosca Structure.pre
screen of Tosca Structure.gui
(GUI).
Analysis Model
- Question: Which file(s) contains the FE-model for the optimization?
- Procedure: Link file(s) to optimization task.
Design Area
- Question: Which surface area of the FE model should be selected for shape modifications?
- Procedure: Assign node group with surface nodes to design area.
- Question: Which area of the model should be selected for
smoothing of the FE mesh?
- Procedure: Assign element group to
MESH_SMOOTH area.
- Question: Are there nodes in the design area or in the mesh
smoothing area that are subject to certain restrictions? How can these
restrictions be described?
- Procedure: Define design variable
constraints for node group.
Objective function
- Question: Which terms describe the values to be optimized?
Should these values be minimized or maximized or otherwise combined?
- Procedure:
Choose terms for optimization (design responses) and target.
Constraint
- Question: Which design response describes the constraint? Which
value should the constraint have?
- Procedure: Choose term for
constraint and set target value or upper/lower boundary.
Optimization Task
- Question: Are all command definitions listed above complete
and ready for the optimization job?
- Procedure: If necessary
complete any additional required definitions and prepare the optimization
job.
Stop Condition
- Question: Should the optimization stop after a number of iterations
(or certain other conditions)?
- Procedure: Define a stop condition.
Check Run
- Question: Would prior testing of the restriction definitions
be useful?
- Procedure: Apply test displacements.
Completion
- Question: Has all the required data been specified?
- Procedure:
If yes, finish the definition of the optimization problem and save your
definition.
The essential commands required for the optimization model in shape optimization
are described in the following. The order of their appearance corresponds
to the order of the above listed procedures.
The definitions for the optimization job are assembled in a parameter
file. The exact syntax of the commands can be looked up in commands manual.
The following figure gives an overview of a standard optimization task
and the relation between the several commands. Only commands which are
referenced in the OPTIMIZE command will be included in the
optimization.