Selecting nodes after substracting 3D components 1

[opotin]

Hi,
My aim is to extract the capacitance value of spires in a polyimide by using the CMATRIX function. To do, I model a 3D block in which I substract 4 spires (torus). But after meshing the block I can't select the 4 torus boundaries to create components (which I will use in CMATRIX function) without selecting the all block.

Any idea ?
Olivier POTIN

 

[kan123]

Did you create surfaces to define the boundary of each torus before generating the element mesh? If so, then the nodes that are created should be associated with those surfaces and can be selected when creating a component.