Hey, I have a domain \Omega in \mathbb{R}^3, which is the unit cube. And in this domain there should be a torus T, so that my right side L is only on the torus (L=0 outside the torus). Is there any documentation where I can read something about this? Or does anyone else have ideas and could give me…

You could probably generate the mesh with gmsh with a torus inclusion using OpenCASCADE .

Thank you. I think I have created the right domain. Can you please take a look and check it? I am not so sure about the boundaries. // Gmsh project created on Wed Aug 4 22:50:25 2021 SetFactory("OpenCASCADE"); //+ Point(1) = {0, 0, 0, 1.0}; //+ Point(2) = {1, 0, 0, 1.0}; //+ Point(3) = {1, 1, 0,…

Hey, I tried to read a 3D mesh from gmsh with from fenics import* import meshio msh = meshio.read("mesh.msh") meshio.write("mesh.xdmf", meshio.Mesh(points=msh.points, cells={"tetra": msh.cells["tetra"]})) but I get the error usr/bin/python3.8 /home/noya/donut.py Traceback (most recent call la…

See for instance: Accessing and marking imported boundaries - #8 by dokken On how to use newer versions of meshio

Hello again, I have now been advised by my supervisor to solve the problem via “submesh”. But for “submesh” I need a “subdomain”. This “subdomain” should be my torus. The representation of a torus is \left(\begin{array}{c} x \\ y \\ z \end{array}\right)= \left(\begin{array}{c} (R+r\cdot cos(\ph…

Hi @Noya , Note that per Wikipedia , the interior of the torus (including the boundary) satisfies \left( \sqrt{x^2 + y^2} - R \right)^2 + z^2 \leq r^2 Therefore, you should be able to define your SubDomain using class torus(SubDomain): def inside(self, x, on_boundary): return (sqrt(x[…

Thank you. But I have know the following problem from fenics import* mesh = UnitCubeMesh(10, 10, 10) r = Constant(0.01) R = Constant(0.2) class Torus(SubDomain): def inside(self, x, on_boundary): return (sqrt(x[0] * x[0] + x[1] * x[1]) - R) ** 2 + x[2] * x[2] <= r ** 2 torus = Torus(…

There are quite a few issues with your code: You do not actually use the torus variable to mark the MeshFunction. After correcting for this, there are quite a few errors due to the usage of dolfin variables, such as Constant and sqrt. These can be corrected as in the code below. Most crucially,…

Thank you. The torus.mark(mf, 1) always caused me errors before and that’s why I commented it out… N = 50 mesh = BoxMesh(Point(-1, -1, -1), Point(1, 1, 1), N, N, N) This creates a cube of the type [-1,1]^3 with mesh with the refinement 50 in each direction?? Now there is createt an \Omega=[-1,…

[image] Noya: This creates a cube of the type [-1,1]^3 [−1,1]3[-1,1]^3 with mesh with the refinement 50 in each direction?? This is correct. [image] Noya: Now there is createt an \Omega=[-1,1]^3 Ω=[−1,1]3\Omega=[-1,1]^3 and the torus T TT with T \in \Omega T∈ΩT \in \Omega . Can I create …

Define a Torus in the UnitCubemesh

mesh

Noya August 10, 2021, 2:09pm 14

Thank you. I have create a new post with all informations. Mesh, Submesh , Torus, Boundary

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Define a Torus in the UnitCubemesh

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