Changing mesh size factor

[Mahmood Naderan]

Hi,

I opened couette_flow_2d.msh with gmsh. I see that the number of meshed are small (mean bigger polygons). I then double-clicked in the screen and used a low value for "global mesh size factor", e.g. 0.4.

Then I clicked on Modules->Mesh->2D and is said "Done meshing 2D". However, screen doesn't show the new meshes and still I see big polygons.

Is that normal?

Regards,
Mahmood

[Brian Vermeire]

Hi Mahmood,

It sounds like what you are trying to do is not a valid way to use gmsh. As far as I am aware, you cannot re-mesh a .msh file like that since the .msh file does not contain the geometry, that is contained in the .geo file.

You need to have the .geo file that defines the geometry, and generate a finer mesh using that. Thankfully, you should be able to make a new .geo file very quickly for that case, since it is just a rectangle.