Sahil Sura
Ansys Employee

This might be an issue due to the computational limitations (eg. memory requirements to run the analysis, etc.) and the complexity of geometry leading to a heavy file. So, you might want to analyze which parts of your geometry are the critical ones and only simulate those with proper boundary conditions.
Another option can be used if your model has boundary conditions symmetric about a specific plane/axis, etc. you might want to take the advantage of the symmetry and solve symmetric region and graphically extend the results.
Some of the references may serve helpful-
Identifying Geometry and Details to Include in a Simulation Using Ansys SpaceClaim - YouTube
Symmetry (
Hope that helps!
Thanks Sahil
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