Uniform Mesh for Circular Geometry in MOOSE

[sskalati]

Hi everyone,

I'm trying to simulate a circular geometry using the meshing tools built into MOOSE. I’ve written the following code using AnnularMeshGenerator

[Mesh]
  [msh]
    type = AnnularMeshGenerator
    nt = 1000
    rmax = 4.1e-3
    rmin = 0
    nr = 80
  []
[]

However, this results in very small elements near the center and progressively larger elements as the radius increases. What I actually need is a uniform mesh throughout the domain, where I can specify the element size directly for instance 0.1mm in my case (as shown in the attached figure).

Is there a way to achieve this in MOOSE? Any suggestions or alternative mesh generators that would work better?

Thanks in advance!

[GiudGiud]

Hello

There are a number of mesh generators that can do circular meshes.
The easiest for a uniform triangular one might be this one
https://mooseframework.inl.gov/source/meshgenerators/XYDelaunayGenerator.html
that would mesh inside a circular curve

This one makes a uniform quad mesh
https://mooseframework.inl.gov/source/meshgenerators/ConcentricCircleMeshGenerator.html
that you can then convert to triangles if you want using this
https://mooseframework.inl.gov/source/meshgenerators/ElementsToSimplicesConverter.html

[sskalati]

Thank you so much! Your comment was incredibly helpful. The XYDelaunayGenerator was exactly what I needed.

I have one more question: If I want to create a cylinder, can I generate a circle using ParsedCurveGenerator, extrude it in the Z direction, and then use XYZDelaunayGenerator?

[GiudGiud]

That is one option though you will also need to create the top and bottom surface meshes as well.

The extrusion can be done from a line mesh or from a sideset.

Alternatively, mesh in 2D then use the AdvancedExtruderGenerator to get a prism mesh