Creating a unstructured triangular mesh or rectangular shape

mesh
1

Hello everyone,

I’ve been looking for a way of creating an unstructured triangular mesh of rectangular shape, but the following function creates a structured one:

mesh = RectangleMesh(Point(0., 0.),Point(N, N), N, N, "right")

however, I’m able to create an unstructured triangular one with circular shape using:

domain = Circle(dolfin.Point(0, 0), N)
mesh = generate_mesh(domain,N,10)

is there a way of combining both functionalities to create an unstructured triangular mesh of rectangular shape?

thanks in advance

2

It is quite straightforward. The built in mesh is structured, but if you use mshr to generate the mesh, it becomes unstructured. See minimal example below.

from dolfin import *
from mshr import *

domain = Rectangle(Point(0,0), Point(2,2))
mesh = generate_mesh(domain, 10)
File("mesh.pvd") << mesh
1 Like
3

Thank you. Is it also possible to create an unstructured quad mesh with mshr?

4

No, In dolfin, in general there is very little support for quadrilaterals cells. In dolfinx you can use quadrilateral elements, with built in meshes, or unstructured meshes creates with for instance gmsh.