# convergence plot

Hello,

This is the plot of a static structural nonlinear simulation.

All the convergence criteria are PC. Only Force and Displacement criteria are available for this simulation, I can see it from the Solver Output. I know that convergence occurs when all the criteria overcome the convergence criterion for a certain number of iterations (don't know exactly how since it varies). Thus, I don't understand why the simulation doesn't convergence in a substep although both the criteria (in this case only Force and Displacement) are below the magenta line for more than three iterations. Sometimes the force and displacement keep being under the magenta line for 50 iterations or more then bisection occurs or divergence happens.

Thanks

## Comments

-Aniket

How to access Ansys help links

Guidelines for Posting on Ansys Learning Forum

Hi,

I have to insert a new image since I'have edited some parameters of the simulation, however the behaviour is quite the same. In this case there is a period of convergence of both criteria (force and displacement) without any substep increment, then a bisection. After that, convergence of substeps occurred, but a new period of non-time increment occurs and persists in this way. There are warnings about large penetration and contact chattering.

Thanks