Layers with different rheological properties

clairewcook

I'm trying to run a model with a couple layers, with the layers having different values for material parameters (B and n). I saw a previous post (https://issm.ess.uci.edu/forum/d/211-running-a-model-with-dissimilar-layers) suggesting this was possible, but I have a couple questions about how to do this.

1) Is it possible to define internal layers in the geometry for a 3d model? I don't mean through extrusion between the surface and the base but using some internal boundary defined by data. And then can you extrude the mesh between the base and the internal boundary and between the internal boundary and the surface?

2) If you have internal layers, either defined as described above, or just from extrusion, how should different material parameters be defined for those layers? I'm assuming you'd do something like md.materials.rheology_B(indices for vertices in the layer)=whatever*ones(number of vertices in the layer) for B and similarly with n except defining it for each element in the layer. But I'm not sure how to access the vertex/element numbering generally (besides for the surface and base).

Thanks,
Claire

mathieumorlighem

Hello Claire,

1) right now, extrude will distribute the layers the same way for each vertical column. That being said... nothing prevents you from manually modifying md.mesh.z if you want the layers to do something specific. Just make sure that the elements are not flipped.

2) we number the layers one at a time. The first vertices (1:md.mesh.numberofvertices2d) belong to the bottom layer. The following vertices (md.mesh.numberofvertices2d+1:2*md.mesh.numberofvertices2d) belong to the second layer etc. So you can do something like this:

for i=1:md.mesh.numberoflayers
md.materials.rheology_B((i-1)md.mesh.numberofvertices2d+1:imd.mesh.numberofvertices2d) = XXX;
end

I hope this helps!
Mathieu

clairewcook

This helped--I was able to modify the mesh and rheology as I was hoping. Thanks so much!