add a 2D option and thickness to Static Current Conduction model

[catalineacsu]

It would be nice to have the 2D option available via a check box for 2D models. Then, for the sake of calculation and final numerical values, a thickness should be entered at some point. For example, I want to simulate the current flow in a thin copper foil, of an arbitrary shape but will always be 2D. The problem is that when I have a cross section and integrate the current, the values are meaningless, since the thickness was never defined. I assume everything is per length unit but if I want to couple this with heating and thus vary conductivity to see the current re-distribution, this model will not work well. Moreover, if I try to model it in 3D with the proper thickness, the results are weird if the foil is very thin, which I assume is due to the grid.

[raback]

I guess that if you want to couple it with heat equation you really need some BCs in the depth direction that break the symmetry. Hence your system will no longer be 2D. You could perhaps also assume some thickness + heat transfer coefficient in the depth direction to obtain a modified 2D heat equation (perhaps the perfusion term could be used already now). So the problems would not simply be solved by multiplying things with thickness. In 3D you should preferably use extruded wedge mesh (rather than tetrahedral) which maintains the translational symmetry better. In principle it would be a good thing to enable thickness to 2D models but going beyond simple multiplication would require quite a bit of effort.

[catalineacsu]

Thanks for coming back on this. I think 2D would indeed be useful. I personally could use it for power integrity in electronics and the 2D would help in comparing different thicknesses. It also makes more physical sense to have current density "injected" in a finite width rather than in a 2D model (with zero thickness). For the thermal coupled scenario I agree any other further addition would break the symmetry. Thanks for the advice on the mesh type.