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Note: When meshing a complex volume, instead of trying to adjust element sizes and geometry detail, it may be useful to use the 'By geometry' and 'Correct incompatible sizes' options, setting the Maximum meshing size as equal to the default size for meshing, and setting the Minimum meshing size to reflect the details (10 times smaller, for example). Sometimes it is also necessary to assign sizes by cordal chordal error.
Assign entities:
This option is used to assign an unstructured mesh to geometrical entities (lines, surfaces or volumes). Using this option it is not necessary to specify an unstructured size for entities; the default size will be set for them.
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