Anisotropic thermal conductivity with falloff question.

Hi all,
I'm trying to define a base material with isotropic thermal conductivity, but with a penetration zone along one axis where the k value falls off from the outer surface toward the center. Essentially, my material is soaked with another material of a higher k value that penetrates to a certain shell depth, falling off logarithmically as it goes deeper.

The way I was thinking of modelling this is defining the k value as anisotropic, with identical x,z scalar values and a changing y value based off of some log function.

I'm moderately new to COMSOL's more advanced features, and I'm not sure how to properly define this in the material properties.

Do you have any pointers/ tutorials/ advice?


Thanks in advance,


Evan