How to set up a non-uniform boundary condition?

[waaizhaq]

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Question

Hello,

I have a rectangular mesh where I set the bottom boundary to a NeumannBC of value 0, representing the ground, the right and top walls to a DirichletBC of value 296.15 Kelvin, representing the ambient air, and currently I have the left wall set to a DirichletBC of value 505.15 Kelvin. However, I want to change that to where only the lower half of the wall is set to the 505.15 Kelvin, and the upper half is another insulated boundary, or NeumannBC of value 0.

[snowbugxs]

I think you may need a section on the domain, then you get two left walls, lower one and upper one. Set different BCs to them.

[waaizhaq]

Do you know an example that I can look at? I was trying to find something on the MOOSE framework but couldn't find what I was looking for.

[GiudGiud]

Hello
Use this generator to split the sideset in two. Then use one boundary condition on one part and another on the other part
https://mooseframework.inl.gov/source/meshgenerators/ParsedGenerateSideset.html

[snowbugxs]

Can we do it outside moose, e.g, using Gmsh to split the domains?

[GiudGiud]

Yes. You can take any mesh generation step in meshing software outside of moose