Rounding errors causing loss of elements
This problem is related to the one that WeiLun asked on the discussion board a few weeks ago.
We are simulating domains which require some very refined regions - cells that are much smaller than the characteristic device dimensions. Rounding errors that seem to be internal to the meshing routine are `aliasing' cells, specifically when the ratio of element size/dimension size >~ 1e7. Note that the format specification precision used in the .msh file is not the limiting factor.
Two examples are attached: 1 structured and 1 unstructured. In these meshes the centre of the square is at (D, 0, 0). The length of the cells is 1 and the length of the square is 10. When D is larger than 1e+7, elements are lost from the mesh.
Any clues to solving this would be greatly appreciated.
Dalton Harvie.