This presentation was made at the 2019 NAFEMS World Congress in Quebec Canada

Resource Abstract

The progressive climate change also requires a rethink in the automotive industry. It is well-known that the heavier the vehicle is, the more energy it needs to get moving. For example, fuel consumption and pollutant emissions can be significantly reduced by optimizing the weight of automobiles.



The use of innovative materials such as advanced composites, which have long been used in the aerospace industry, can also be used in future vehicle constructions to meet the energy consumption requirements. Regardless of the branch of industry, lightweight structures must be the goal of our efforts to use raw materials more sparingly.



In that context, the CAE software must not only support laminates but also optimization methods with regard to their design. In the optimization of laminates, which can often be characterized by orthotropic material behavior, the layer thicknesses and ply angles are available as design parameters in addition to the material parameters. Constructive restrictions such as discrete ply angles, a symmetrical and balanced stack reduce the dimension of the optimization problem.



Furthermore, the value ranges of the material characteristic values are subject to restrictions due to the positive definiteness of the strain energy, which differ depending on the underlying material law (e.g. transversal isotropic, orthotropic).



This contribution analyses the application of optimization methods in the environment of laminate structures with respect to the identification of material parameters and the optimization of laminates with respect to certain target functions and corresponding constraints.



Only a successful application of optimization methods in practice can increase the acceptance in design departments and thus justify the area-wide application of optimizations from the beginning of the product development process. All computations are carried out in PERMAS, whereas post-processing is done in VisPER and permasgraph. PERMAS specific keywords are denoted by capital letters and a preceding dollar sign in the subsequent text.