General Mechanical

General Mechanical

Solver engine convergence error

    • tahm
      Subscriber

      I am getting this error message. How to resolve?


      The solver engine was unable to converge on a solution for the nonlinear problem as constrained.  Please see the Troubleshooting section of the Help System for more information.

    • Keyur Kanade
      Ansys Employee

      As ANSYS Staff, we can not download attachments. Please insert images using insert image functionality. 

    • tahm
      Subscriber


      Here are some screenshots

    • tahm
      Subscriber

      I was doing a 2D plane strain analysis of soil element

    • peteroznewman
      Subscriber

      Increase the Initial and Minimum Substeps to 100.


      Insert a command object


      NEQIT,50

      This will tell the solver to keep going for 50 iterations instead of doing a bisection or stopping after 26 iterations.

    • tahm
      Subscriber

      Still I am getting the error


    • peteroznewman
      Subscriber

      You have to improve the element shape where the solver is unable to obtain a force equilibrium and fails to converge.


      You can find out where that is by typing a 4 in the field called Newton-Raphson Residuals under the Solution Information Folder.  Take out the NEQIT command. Solve. When if fails to converge, you will have 4 plots under the Solution Information folder. The plot is the Newton-Raphson Force Residual plot. The Maximum value on this plot is where you need better elements.


      I already know that it will be in the interior corner.  If you put a small radius in that corner instead of a sharp interior corner, that will help it converge.

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