Let's check accuracy for 8 nodes Solid Hex Element
In this video, the focus is on comparing different types of solid elements: linear tetrahedral, quadratic tetrahedral (with mid-sides), and linear hexahedral elements. The linear tetrahedral elements may lack accuracy for many tasks, requiring a very fine mesh. The linear hexahedral elements, however, show comparable accuracy to the nonlinear tetrahedral elements but with fewer nodes. Stress distribution is examined, revealing that linear hexahedral elements can be a more efficient choice in terms of both accuracy and computational resources. But linear hexa mesh need some accuracy and understanding from FE engineer.
The absence of quadratic nonlinear hexahedral elements is left for viewers to consider and comment on.