Sahil Sura
Ansys Employee

Hexahedral elements are 3D elements used for 3D analyses. Quad and Tria elements prove useful for 2D analyses.
For 2D analysis, mapped meshing serves useful to get a structured mesh.
You can add the 'sizing option', and select the edge, set the 'Type' to 'Number of divisions' and specify the same. Since the width remains constant this method works the best.
Hope that helps.
Thanks Sahil