Learning Forum

[turgut.ataseven]

Hi. I am trying to perform an analysis of pin breakage with Nonlinear Adaptive Region (Energy Criterion) on the section that will break. Even though Energy Coefficient is 0,4 and maximum stress that occurs on the section is  MPa, any split had not occured. Mesh on the Nonlinear Adaptive Region section and its connecting regions have quadratical tetra mesh. What should I do? Mesh Criterion does not feel right since stress concentration occurs.

[Giorgos Papa]

Hello,

 

There are several possible reasons why your model may not be remeshing, even when it seems like it should:

 

1. Checking frequency criteria

The program evaluates the nonlinear mesh adaptivity criteria at set intervals—either after a specified number of substeps or at equally distributed points throughout the load step or defined time interval.

This frequency is controlled in the Check At field under the Nonlinear Adaptive Region object details, with two available methods: Specified Recurrence Rate or Equally Specified Points.

You may need to experiment with these input values to determine the frequency that best suits your model and criteria. More details can be found in the Ansys Help documentation:

https://ansyshelp.ansys.com/account/secured?returnurl=/Views/Secured/corp/v252/en/ans_nlad/advnlcritcheckfreq.html

 

 

2. Remeshing attempt not successful

It is also possible that the solver attempted to remesh but failed to generate an adequate mesh, in which case it proceeds with the original mesh. You can confirm whether a remeshing attempt was made by checking the solver output file.

If this occurred, you can adjust the Adaptivity Remeshing Controls in Analysis Settings to improve the chances of generating a better mesh. Fine-tuning these controls may be necessary, since the optimal configuration can vary depending on the model.

 

Note: Remeshing controls are often model-specific, so achieving optimal results may require some trial and error.