Assessment of computational models for sandwich panels and shells

Abstract

A study is made of the effects of variation in the material and geometric parameters of curved sandwich panels on the accuracy of the static response predicted by nine different modeling appraoches based on two-dimensional shell theories. The standard of comparison is taken to be the exact three-dimensional thermoelasticity solutions, and the quantities compared include gross response characteristics (e.g. strain energy components, average through-the-thickness displacements and rotations); detailed, through-the-thickness distributions of displacements and stresses; and sensitivity coefficients of the response quantities (derivatives of response quantities with respect to material and geometric parameters of the sandwich structure). Extensive numerical studies are conducted to assess the accuracy of both the global and detailed response characteristics and their sensitivity coefficients obtained by nine two-dimensional modeling approaches. For accurate determination of detailed through-the-thickness distributions such as transverse stresses, either high-order discrete three-layer models or predictor-corrector approaches are required. The potential of predictor-corrector approaches for predicting the thermomechanical response of sandwich panels and shells with complicated geometry is also discussed.