A comparison of Ansys Shell181 and Solsh190 elements

Please find attached a report on a comparison between ANSYS SHELL181 and SOLSH190 elements with particular emphasis on applicability to linear elastic sandwich panels.

Title: Comparison of Ansys elements Shell181 and Solsh190

Abstract:

 Plate and shell elements are indispensable for the study of the mechanics of complex structures. Two classes of shell elements are commonly used in finite element analyses of thin structures, classical two-dimensional lements and three-dimensional continuum elements. Users of commercial finite element software, such as ANSYSTM , are often unsure of the relative strengths and weaknesses of these elements and of the appropriate use of these elements. This report provides data that can be used as a basis for the selection of shell elements for engineering analysis and design. The displacements and stresses predicted by two ANSYSTM shell elements, SHELL181 and SOLSH190, are compared with exact solutions and full three-dimensional simulations for several geometries and boundary conditions. We conclude that classical shell, SHELL181, elements and solid shell, SOLSH190, elements behave in a similar, though not identical, manner for many situations. For instance, SHELL181 elements generate poor solutions compared to SOLSH190 elements for sandwich plates with isotropic layers and small core to facesheet stiffness ratios. However, for low stiffness cores of moderately high shear stiffness, both SHELL181 and SOLSH190 elements perform adequately. We also note that plates modeled with a single layer of SOLSH190 elements are extremely stiff in bending and we recommend at least three elements through the plate thickness for reasonable results. Also, boundary conditions have to be applied to all the nodes of SOLSH190 elements to achieve the correct mid-surface deformation behavior. The solid shell element provided by ANSYSTM can be used to replace standard shell elements provided care is taken during its use.