Dynamic Analysis of Variable Thickness Shells in Aerospace Applications via CUF Adaptive Finite Elements

New technologies and tools lead to design structures with increasingly more complex and disruptive geometries. In the field of thin structures, such as plates and shells, it is necessary to have numerical analysis tools that take into account these innovations and the use of advanced materials, such as composites, metamaterials or sandwich plates, or in general muti-layer materials. Within the Carrera’s Unified Formulation (CUF) framework, this article proposes a formulation based on adaptive finite elements that can study complex geometries, as variable thickness plates or with edges not orthogonal to the midsurface, while retaining the advantages of CUF theories for the study of multi-layer structures, both in terms of accuracy and reduced computational cost. The adaptability of these new elements concerns both the geometry and the possibility of using different structural models within the same element. Two case studies are presented in the following paper in order to demonstrate the new formulation: a plate with a topology optimized thickness and a semi-cylinder with a sinusoidal thickness.