[Yann]

Hello Nafiz,

If you want to refine a zone inside your mesh you can do it directly in snappyHexMesh: define a box in the geometry section and then use it refinement regions.

geometry
{
    a_box_for_refinement
    {
        type box;
        min  (1.5 1 -0.5);
        max  (3.5 2 0.5);
    }
};

refinementRegions
    {
        a_box_for_refinement
        {
            mode inside;
            levels ((1.0 4)); // refine to level 4 inside the box
        }
    }

More details in the documentation: https://doc.openfoam.com/2306/tools/...inementRegions

Regards,
Yann