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The Shape to be meshed could be set to: From mesh or from geometry.
In case of 'From mesh' a an auxiliary unstructured mesh of triangles will be generated and will be used as input for the cartesian mesher. This intermediate mesh will be deleted at the end, and in any moment will be visible for the user.
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Now assign to the volume number 3 a specific size=0.8 in all directions. Select
Mesh->Assign cartesian size→Volumes
and select the volume number 3 (on the right of the images) finishing with a double <Esc>
and generate again a mesh with general size=2.0. You will obtain a non-uniform mesh like these:
In case of Variable spacing, the Minimum size try to avoid a too small edge size, and the Size ratio try to avoid big differences of sizes between two consecutive edges.
The grid is automatically defined when generating the mesh (based on the current geometry and mesh sizes), but the user could set its own definition:
In preferences check User defined, press Apply to accept it, and then the Grid window... button become enable. Pressing it, a window like the following one appears, filled with the current values:
In this window it is allowed to modify the location and size of the box, set the number of divisions and set the values of the ticks editing the values of the table.
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