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How to prevent Model Remeshing while solving after Updating Boundary Selections (No Geometry Change)

Posted 04.12.2025, 15:14 GMT-5 Geometry, Mesh, Modeling Workflow Version 6.4 0 Replies

Aragorn

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Hi,

In my workflow, I use a union of ball selections(created in geometry, after Form Union) to identify and select new boundary surfaces. Then, I update the boundary conditions with these newly created selection sets. Importantly, I do not modify the actual geometry, just create an union of different ball selections to use as boundary.

Here’s a simplified snippet of my code where the BCs are assigned and then the study is run:

model.component('comp1').physics('ec').feature('term1').selection.named('geom1_termUnion'); model.component('comp1').physics('ec').feature('gnd1').selection.named('geom1_groundUnion');

model.study('std2').run;

termUnion and groundUnion are unions of several ball selections.

However, when I run the study, COMSOL remeshes the entire model before solving. I would expect that only the solution should update, there should be no reason to regenerate the mesh if the geometry hasn’t changed. That is the entire idea of using ball selections.

Why does COMSOL trigger a remesh in this situation, even though only boundary selections have changed? Is there a way to prevent unnecessary remeshing when updating boundary conditions via selection sets?

Any tips would be greatly appreciated! Thank you in advance for your help.

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