CFD Online Discussion Forums - Convert existing gmsh mesh to second order?

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Convert existing gmsh mesh to second order?

Hello everyone,

Quick question about gmsh. Is there a way to take an existing gmsh .msh file, and convert it to second order elements? Specifically, I'm trying to go from 8-point hexahedra (hex8) to 20-point hexahedra (hex20). Ideally, I'd like a command-line solution. I tried this:

Code:

gmsh -o output.msh -format msh2 input.msh -order 2 -0

But it doesn't seem to work - I still get hex8 elements in the output. Is there a way to do this, or does the order need to be set when the mesh is first generated?

Thanks

Answered my own question - you can do it using a gmsh script (i.e. a .geo file).

Code:



Merge "input.msh";



SetOrder 2;



Save "output.msh";

Saving that as "convert.geo", you can then run:

Code:

gmsh convert.geo -0