Elements selection in different conditions

1. In 2D analysis, whenever we change element order from 1st order to 2nd order, there is no need to update the contact elements defined on 1 order elements. 
2. Make all elements as “well shaped” as possible to improve convergence and accuracy. 
3. If an automatic tetrahedral mesh generator is used, use the second-order elements C3D10 (in Abaqus/Standard) or C3D10M (in Abaqus/Explicit). If contact is present in Abaqus/Standard, use the modified tetrahedral element C3D10M if the default “hard” contact relationship is used or in analyses with large amounts of plastic deformation. 
4. If possible, use hexahedral elements in three-dimensional analyses since they give the best results for the minimum cost. 
5. Use second-order, fully integrated elements close to stress concentrations to capture the severe gradients in these regions. However, avoid these elements in regions of finite strain if the material response is nearly incompressible. 
6. For linear and “smooth” nonlinear problems use reduced-integration, second-order elements if possible. 
7. Use first-order quadrilateral or hexahedral elements or the modified triangular and tetrahedral elements for problems involving contact or large distortions. If the mesh distortion is severe, use reduced-integration, first-order elements. 
8. If the problem involves bending and large distortions, use a fine mesh of first-order, reduced-integration elements. 
9. Incompatible mode elements can give very accurate results in problems dominated by bending.