Discussion Forum

Hi all.

I am new to comsol and have a problem I could not find a solution to in the manuals.

I am using the Electrostatics package (in rotation symmetry 2D) to compute a potential (field) map. I used geometry building blocks for the electrodes and the casing and this works very well.

Then i wanted a much higher mesh resolution in a small part of setup, so that i can extract a highly precise fieldmap from this area. Therefore I defined a rectangular geometry and used a seperate mapped mesh + distribution with a high number of points on the geometry borders (maybe there is a better way to do this?).

My Problem now is, that i need to introduce a elliptically shaped space charge inside of this mentioned area. I defined an elliptic geometry and assigned the domain a spacecharge. But because of this new geometric object, the automatic meshing takes the elliptic border into account and distorts the original mesh, with the added effect that the calculated potential in the space charge area is very "spikey" (=discontinous, therefore high fields where actually no field should be present at all and i think this comes from the mesh, as it looks like it changes its properties stongly with different meshes) .

My question now is: Can i somehow tell comsol, that it should ignore the elliptic area (domain) for meshing purposes? I want to retain the ortogonal mesh from the rectangular geometry and it should penetrate the elliptic area as if it is not there at all.

Thank you.


PS: If I export my data in spreadsheet format and use the grid option, so that the extracted points do not coincide with the mesh points, what kind of interpolation is used in that case? Nearest neighbor, linear, n-spline?