Maximum Iterations per Stage edit box. When target-force loads are applied in a nonlinear static load case, deformation load is iteratively applied to achieve the target force. Each iteration is a complete nonlinear static analysis, or stage thereof. Many iterations may be required for some structures, and each iteration may take some time. Start with a moderate value, such as 5 or 10, and increase it as necessary. Set this value to zero (0) to prevent target-force iteration.
Relative Convergence Tolerance edit box. This is the error you are willing to accept in the target forces. Since target forces represent your desire, and not a natural requirement like equilibrium, a large value such as 0.01 to 0.10 is recommended.
Acceleration Factor edit box. The difference between the target force and the force actually achieved is converted to deformation load and applied in the next iteration. You can increase or decrease this load by the acceleration factor. Use a value greater than 1.0 if convergence is slow, such as when pulling or pushing against a flexible structure. Use a value less than 1.0 if the solution is diverging, i.e., the unbalance is growing or oscillating between iterations.
Continue Analysis if No Convergence option. Since achieving the target forces is not a natural requirement, and may not even be possible, you may want to continue the analysis even if the target is not reached.
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The target-force iteration option is one of the Solution Control area/options that appear on the Nonlinear Parameters form. Access the Nonlinear Parameters form as follows:
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