Global Stop Criterion (Number of Iterations)

The stop criterion is the maximum number of optimization iterations, which is default 50 for sensitivity-based and 15 for controller-based optimizations. When the maximum number of optimization iterations is reached, the optimization algorithm always stops independent on the values of the two previously mentioned criteria. The allowed maximum number of optimization iterations can be increased or decreased by the user. This is defined by the parameter ITER_MAX of the STOP command.

STOP
 ID_NAME  = global_stop
 ITER_MAX = 55
END_

where ITER_MAX is increased to 55.

Important: The global stop criterion is defined using a STOP command whereas the convergence criteria are defined in the optimization settings ( OPT_PARAM command). The global stop criterion leads to a stop of the optimization, independent of a complete convergence of the result (in particular with a small number of iterations this cannot be achieved). For the controller-based algorithm, the number of iterations required for full convergence is set using the SPEED= ITER,<nr> parameter in the OPT_PARAM) command. If there are stress design responses or nonlinear materials present in the optimization, the default maximum number of iterations will be automatically set to 80.