Troubleshooting FEM Mesh Generation
The following may prevent mesh generation in part mode:
• Imperfections in model geometry—Use > > to investigate the features flagged by the software. Resolve any errors or warnings before meshing the model.
• Insufficient data—When the software is unable to mesh, the mesh generator may prompt you to apply more mesh controls to specified geometry. If the error message appears again after applying the appropriate mesh controls, you should evaluate the model for the presence of invalid geometry.
• Inappropriate mesh controls—If the software is unable to generate a mesh, your model may include mesh controls that are inappropriate to the geometry. You can experiment with adding, changing, or removing mesh controls to determine which mesh control causes the problem. You may also be able to isolate problem geometry by suppressing some features.
When you attempt to generate a mesh in assembly mode and the system gives you an error message, also consider the following:
• Interference—The mesh generator cannot mesh assemblies that have interference. Use the > command and resulting Model Analysis dialog box to check for global interference in your model.
• Minimum element size—A Minimum Element Sizemesh control set for one part may not be appropriate for the entire assembly. If this is the case, remove all Minimum Element Size mesh controls assigned to the parts and try to mesh the assembly again. If you are still unsuccessful, remove all Maximum Element Size mesh controls as well.
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If you are working at the assembly level, you can often use Ignored Mesh Control on the Mesh Control dialog box instead of actually removing the mesh controls from lower-level components.
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• Design flaws—Design flaws in model geometry—such as misalignment, overlapping geometry, and other imperfections in part geometry—can often prevent the mesh generator from meshing assemblies even if it could successfully mesh constituent parts in part mode. You may need to temporarily suppress some components and attempt to mesh the assembly so you can determine which parts cause the problem. After you find the problem parts, try to eliminate imperfections.
• Curved surfaces—Some assemblies contain curved surfaces on the components that are close but not touching—for example, two concentric cylinders of similar but not equal diameters. In this case, place a local maximum, equal to the clearance, on the two opposing curved surfaces.
• Accuracy values—Accuracy values of the parts in the assembly must be compatible. It is better for large models to have accuracy values comparable to smaller models. If you have problems generating a mesh for an assembly, you can run a report to check the accuracy values of each assembly component. This report shows you which components have tolerance values that are too high so you can adjust them.
When the software fails to generate a solid mesh, check the available memory. If you receive a memory error message, you can increase the amount of memory that Creo Parametric uses by modifying the sim_max_memory_usage configuration file preference.