Tetrahedral mesh as required and Pass variables carried by nodes during grid processing

#1

Dear developers,

   Recently, I try to apply MMG in the following two aspects: 
   1. Refine any tetrahedral mesh on demand; 
   2. In the process of tetrahedral mesh adaption, passing variables carried by mesh nodes.
   I wonder if MMG can meet the above two demands? And is there any guidance document about this field? If MMG cannot do that, could you provide some advice on meeting  these demands based on the codes in MMG?
#2

Hello and thank you for trying Mmg,

  1. Normally you should be able to refine any tetrahedral mesh.
    You just have to provide:
  • a suitable value for the hausdorff parameter. This value can be local if your mesh represent an object embedded in an “infinite” space (Parameter file – Mmg Platform). Otherwise you can simply use a global hausdorff value using the -hausd command line argument (-hausd – Mmg Platform);
  • eventually, either a nodal size map (isotropic or anisotropic), or size parameters (-optim to respect the input edge length or -hsiz to impose a constant edge size).

A description of the mesh adaptation behaviour of Mmg is available for mmg2d (Mesh adaptation to a solution – Mmg Platform) and mmg3d (Mesh adaptation to a solution – Mmg Platform).

  1. I am not sure to understand what do you mean by variables : do you want to interpolate fields defined at input mesh node on the final one? If yes, Mmg doesn’t provide such tools but you can use the AdaptTools repository of the ISCDToolbox organization on github (GitHub - ISCDtoolbox/AdaptTools: Tools for mesh adaptation). The branch olderVersionThatWorks provides metric computation and P1 interpolation of nodal solution for 2D and 3D meshes.

I hope that it will help,
Best Regards,

Algiane