Selecting shell elements

Several guidelines are provided for selecting shell elements.

  • The linear, finite-membrane-strain, fully integrated, quadrilateral shell element (S4) can be used when greater solution accuracy is desired, for problems prone to membrane- or bending-mode hourglassing, or for problems where in-plane bending is expected.

  • The linear, finite-membrane-strain, reduced-integration, quadrilateral shell element (S4R) is robust and is suitable for a wide range of applications.

  • The linear, finite-membrane-strain, triangular shell elements (S3/S3R) can be used as general-purpose elements. A refined mesh may be needed to capture bending deformations or high strain gradients because of the constant strain approximation in the elements.

  • To account for the influence of shear flexibility in laminated composite shell models, use the shell elements suitable for modeling thick shells (S4, S4R, S3/S3R, S8R); check that the assumption of plane sections remaining plane is satisfied.

  • Quadratic shell elements, either quadrilateral or triangular, are very effective for general, small-strain, thin-shell applications. These elements are not susceptible to shear or membrane locking.

  • If you must use second-order elements in contact simulations, do not use the quadratic, triangular shell element (STRI65). Use the 9-node, quadrilateral shell element (S9R5) instead.

  • For very large models that will experience only geometrically linear behavior, the linear, thin-shell element (S4R5) will generally be more cost-effective than the general-purpose shell elements.

  • The small membrane strain elements are effective for explicit dynamics problems involving small membrane strains and arbitrarily large rotations.