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AutoGEM Overconstrained
We recommend that you run AutoGEM against all of the surfaces and volumes in your model at the same time. This approach assures a cohesive mesh.
However, if you mesh your model in stages, selecting volumes one or two at a time, examine the volume interfaces before you start. Be sure to use AutoGEM on the volume that includes the smallest features near the interface before you use it on the volumes with larger features.
This is because, after you use AutoGEM on one of the volumes in a model, the element faces on that volume become constraints that AutoGEM must respect while processing other adjacent volumes. If you start with volumes that have larger features near the interface, the existing large elements at the volume interface may overconstrain AutoGEM when you then try to mesh adjacent volumes with smaller features.
You can correct this situation through the AutoGEM Settings dialog box. In this case, you select Modify or Delete Existing Elements and select the volume filled with elements as well as the unfilled volume. AutoGEM then completes the unfilled volume and modifies the existing elements in the filled volume as required.
Return to How AutoGEM Uses Existing Elements.