Description: DistMesh giving a singular FEM matrix?-Hi
Anyone here with some experience of using DistMesh in finite element code? I m solving the scalar Helmoltz equation in an annular region in 2D:
rho_1 < rho < rho_2
where rho_1 is the radius of a Perfect Electric Conducting cylinder and rho_2 is where the mesh is truncated using an Absorbing Boundary condition.
Now, I ve written code to mesh the region myself (by dividing the region into annular rings and picking a fixed number of points on each ring) and I ve written another program which uses DistMesh to mesh the region. I get a nice solution using my own meshing code but the FEM matrix becomes singular when I use DistMesh. This is the DistMesh Code I used:
Circle with hole
rABC=1.5
rCyl=0.5
fdstring=sprintf( ddiff(dcircle(p,0,0, f),dcircle(p,0,0, f)) ,rABC,rCyl)
fd=inline(fdstring, p )
box=[-2,-2 2,2]
[p,N]=distmesh2d(fd,@huniform,0.04,box,[])
I tried changing box and the 0.04 value (initial edge length). But every time, the matrix becomes sin Platform: |
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Author:skypigr |
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