For an electro ohmic quasi-static simulation, there is a check mark to specify a material setting as anisotropic, which will enable fields to enter conductivity on and off the diagonal of xx/yy/zz. As far as I understand it, this works well for a geometry with a fixed orientation/axis, but is there a way to specify the anisotropy with respect to a spline used to create the geometry (such as for muscles or nerves)? One might imagine this as using a local coordinate system rather than the global coordinate system.
Thank you for the help
Material anisotropy along a curve?
For this you would need to use the homogeneous anisotropic conductivity. The easiest way to use that feature I think, may be to create the field distribution in Python as a FloatFieldData on a RectilinearGrid and add this to the Analysis tree via the "TrivialProducer". You can then select the anisotropic conductivity from the Analysis pipeline.
Anisotropic conductivity distributions along a spline are sometimes computed by solving a Poisson equation in a tube, with Dirichlet boundary conditions at the top and bottom. This gives a main direction for the anisotropic tensor along the spline. You can create a tube from a spline using the "Thicken Wire" tool (or in Python: XCoreModeling.ThickenWire).
Since this seems to be an important question, maybe somebody who has a working script to assign homogeneous anisotropic conductivities can share it here as a reference.