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Limitations for Meshing Large Assemblies
When meshing assemblies that contain components of sizes that differ by orders of magnitude, you may experience the following:
If you mesh an assembly considering the meshing requirement of a larger component, the same mesh may not fulfill the meshing requirement of the smaller components. As a result, the mesh generation may fail for smaller assembly components.
If a significant difference exists between the geometric accuracy of two parts in an assembly, it is difficult to create a cohesive assembly that includes both parts. In this case, if you were to mate the two components, the differences in tessellation refinement could cause geometric incompatibilities.
This is of particular concern for meshing, where the software uses the geometry to determine element edge length, element size, and so on. For instance, if you mated the two example parts along a nonlinear curve, Creo Simulate might experience problems in trying to match the small elements that would be a byproduct of the small part's refined tessellation with the larger elements that the larger part's coarser tessellation would produce.
While assembling components that were modeled in different unit systems, the absolute tolerance for the individual component is converted into the assembly units. This may also cause significant differences in the tolerance values of components.
Even if mesh generation succeeds, Creo Simulate will generate a coarse mesh with large-sized elements considering the meshing requirement of a larger component in the assembly. Such a coarse mesh may generate only a few elements for the smaller components in the assembly. As a result, the solver may not be able to produce accurate results for the smaller assembly components.
Refer to the meshing guidelines for meshing such assemblies.