The default solution controls in ANSYS typically do not allow for a robust and efficient solution in a progressive failure simulation of a composite structure. Specific solution control parameters allow for a solution with decreased tendency for time increment cutbacks when used with Simulation Composite Analysis. This results in a faster overall solution time. These solution controls are defined in the following steps. For further information regarding each command, refer to the ANSYS documentation and the Simulation Composite Analysis User's Guide.
Enter the following commands into the command window:
- NROPT, FULL, , OFF - This command instructs ANSYS to use the 'Full' Newton-Raphson algorithm and prevents it from using the 'Adaptive Descent' algorithm.
- PRED, OFF, , OFF - This command prevents ANSYS from using the converged solution at the last substep to estimate the solution for the current substep.
- NSUBST, 100, 100, 100 - This command specifies the number of substeps to be used in the analysis. Since the step time is 1, each substep time increment will be 0.01.
- NEQIT, 1000 - This command specifies the number of equilibrium iterations that must be performed before ANSYS evaluates the need to reduce the time increment size. It is intentionally large in order to force ANSYS to converge at each of the specified time steps.
- TIME, 1 - Specifies a step size equal to 1.