Reply To: Newton-Raphson Residual

[peteroznewman]

The convergence chart that shows the maximum value of Newton Raphson residual versus iteration number is always shown, but what you want to see to is a plot of the location of the maximum value of NR residual on the mesh. Knowing the location allows you to add a mesh control at that location to improve the element quality and usually to use smaller elements to help the convergence.  The plot is not automatically created, you need to turn it on by typing a number larger than 0 on Netwon Raphson Resuidual line under the Solution Information folder.  Then after a Solve, there will be as many plots to look at as the number you typed. Each plot is for the last few iterations.

https://innovationspace.ansys.com/knowledge/forums/topic/how-to-use-the-newton-raphson-residuals-option-under-solution-information/

There are other things to do to help convergence. Under Analysis Settings, turn on Automatic Time Stepping, then under that set the Initial and Minimum substeps to a value such as 10 and the Maximum Substeps to 1000. You have to do that for each step in the solution sequence.

https://www.padtinc.com/2012/10/10/overcoming-convergence-difficulties-in-ansys-workbench-mechanical-part-i-using-newton-raphson-residual-information/