Constraints for array variable on boundaries

[pj131611]

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Question

Greetings!

I'm looking for a constraint function that constrain the boundary value of the same variable through multiple boundaries. But the problem is I'm working with array variables and I couldn't find a constraint for array. So my question is does such function exist? If not, would it be reasonable to write a constraint function that inherit from EqualValueBoundaryConstraint or TiedValueConstraint but with array variable and component as input?

Thanks

[GiudGiud]

Hello

No I don't think we have that at the moment but feel free to implement it.
Please let us know if you hit any difficulties doing so

[pj131611]

Cool. I started with inherit from Constraint class and replace the variable with arraymoosevariable and here comes the first problem while testing:

*** ERROR ***
Unknown type of Constraint object

After doing a little bit of digging around, it seems like I need add this new constraint into Constraint Warehouse and objects, which will make me re-make moose. Is there a way to avoid this? It takes way too long to re-make the whole moose framework.

[GiudGiud]

hello

the Constraint class should be the base class for your new objects most likely.
It only brings a variable parameter which you can use and some background calls to the subproblem to trigger the right kind of re-iniit.

If you inherit from the Constraint class, your object will be added to the Constraint warehouse as expected

[pj131611]

Hi there!

A surprising problem arise while I'm trying to simplify the mesh: Is there a way to convert the input unstructured mesh(triangles and simplex) to structured mesh(squares and cubes)? It seems a lot easier to play with structured mesh.

[GiudGiud]

not in a general way. Most shapes described with unstructured mesh cannot be described with structured meshes

You can generate simple structured meshes with this:
https://mooseframework.inl.gov/source/meshgenerators/CartesianMeshGenerator.html

Under the hood they are still represented as unstructured meshes though. MOOSE does not support the libmesh structured mesh