High Performance 3D-Analysis of Thermo-Mechanically Loaded Composite Structures

Abstract

An integrated analysis process for thermally and mechanically loaded composite structures is presented which uses a shell finite element model throughout. Thermal Lamination Theories and related finite elements developed by the first author are used for the 3D thermal analysis. The stress analysis is carried out using the same geometry model but with different mesh density. Interpolation between the different meshes can be accomplished automatically since both discretizations are defined on the same geometry. Standard shell elements based on the First Order Shear Deformation Theory (FSDT) provide the three in-plane stress components. A novel postprocessing scheme is adopted for determining all transverse stress components from the in-plane stresses and the temperature field. The postprocessing methodology is based on the new extended 2D-method which utilizes the material law for transverse shear and the 3D equilibrium conditions. Thus, the integrated analysis process provides full 3D information without any 3D discretisation. The interaction of thermal and stress analysis is demonstrated by the example of a composite wing box for a future large airliner.