How to deal with ""Problem terminated -- degenerate cells""?"
|
Firstly, make sure the grid for all parts is correct before running AUTODYN. Then, carefully examine the material properties used in the AUTODYN calculation. Next, if the grid and material properties are okay, follow the instructions below: 1. If the Lagrange processor was used in your AUTODYN model and you do not want to change it to another processor, you may need to specify an erosion model for the material in the part containing the degenerate element. Erosion models are defined in the Material Modify panel. 2. If the ALE processor was used in your AUTODYN model and you don't want to change it to another processor, you may need to change the motion constraint in the ALE part. The default motion constraint is Lagrange. The motion constraint can be changed in the Parts panel by pressing the Motions button. Specifying any motion constraint other than Lagrange will help to automatically rezone the grid. The most frequently used motion constraint is Equipotential. 3. If you don't want to use the Lagrange processor in your AUTODYN model, you can choose to use the SPH processor, or ALE processor with Eulerian motion constraints, or Euler processor. SPH is a meshless processor and thus has no degenerated cells. Using the ALE processor with Eulerian motion constraints can automatically rezone the nodes in the part and thus reduce distortion of the mesh. In Euler processors nodes do not move, rather the material flows from one cell to another. |
||
|