Maximizing the First Natural Frequency of the Plate Model (Tosca ANSA® environment)

The set-up including starting a TOPO_SENSITIVITY task, loading the model and definition of design area, objective function and constraint can be done as described in the Getting Started Manual.

Related Topics
About Checking the Quality of the Optimization Result

  1. To define the objective function as the maximization of an eigenfrequency, select in the task manager PRE_PROCESSING | OBJ_FUNC_ITEM_1 | NEW | EIGENFREQUENCY.

  2. In the OBJFUNC_TERM item, choose the DYN_FREQ_KREISSEL type.

  3. To select the eigenmodes, do the following:

    1. Activate the LC_SET field and enter ?.
    2. In the LC_SET dialog, choose the first 5 eigenmodes:



      Note: It is not absolute necessary to change the APPROACH to MODAL, if there is only a modal analysis defined in the input deck. If only one load case exists, the LOADCASE fields can be left empty.

    3. To add load case definitions, use the button MORE.

  4. To set the filter radius, select in the task manager PRE_PROCESSING | TOPOLOGY_OPTIMIZATION_SENSITIVITY | NEW | SETTINGS and specify a 25 mm filter radius.

The optimization result looks as follows:

The convergence plot for the Objective Function is as follows: