2D Elements in Meshing for Finite Element Analysis (FEA)
Two Dimensional (2D) Elements, also commonly known as planar / shell elements are used in Finite Element Analysis (FEA) problems that predominately consist of thin or sheet based structures that the 2D plane’s dimensions are very large in comparison to the 3rd dimension, expected failure to be of bending deformation nature and consistent material properties over the entire model. They are also easier to model compared to 3D and solving time is faster than 3D models.
2D Elements are most recommended to be carried out on the mid-surface of the actual geometry. This approach allows the omission of detailed volume mesh as the thickness of geometry is virtually assigned to the 2D Elements. Mathematically, the element thickness is assigned with half in the +Z direction (top) and the other half in the –Z direction (bottom).
For the use of Two Dimensional (2D) Elements or planar / shell elements in Finite Element Analysis (FEA) problems, there are 2 major types of 2D Elements; Triangular & Quadrilateral.
Three noded triangle, also known as Constant Strain Triangle (CST) is of linear element nature, having 6 displacement degrees of freedom (DOFs) per element.
Six noded triangle, also known as Linear Strain Triangle (LST) is of parabolic element nature, which is a higher order triangular element, having 12 displacement degrees of freedom (DOFs) per element and quadratic displacement function.
Four noded rectangle, is of linear element nature, having 8 displacement degrees of freedom (DOFs) per element.
Eight noded rectangle, is of parabolic element nature, having 16 displacement degrees of freedom (DOFs) per element.
Quadrilateral elements are always more accurate compared to Triangular elements because displacements are interpolated to a higher degree in quadrilateral than in triangular elements.
Do you benefit from the knowledge of 2D Elements used in Finite Element Analysis (FEA)? Speak to your friendly consultant in NAC Consultancy or drop us a mail at sales@nac.com.sg to discuss more on the application of 2D Elements used in Finite Element Analysis (FEA)!
 |
Johnny Wong Senior Consultant, Partner NAC Consultancy Pte Ltd |