Advanced Solver Settings : Convergence Control

The relaxation solution is iterative, and these parameters control the iterative process. They can be adjusted if convergence problems are experienced, or to speed up analysis.

Definition

Number of Cycles to Check Residuals

The convergence of the solution depends on the magnitude of the residual vector, however checking the residual takes time so it is usual to not calculate this at every time step.

Dummy Mass Update

A dynamic relaxation solution assigns dummy mass to the nodes which is updated during the solution. In general it is best to leave the updating to the Automatic option, but the user can also take control of how frequently this happens. In some cases it may be better not to update the dummy mass, and instead specify a dummy mass factor directly.

Damping

There is a choice of using viscous damping (based on the pseudo velocities) or artificial damping (based on displacements). This can be handled automatically. or with a user defined percentage of damping.