Abstract: he stiffener layout optimization of thin walled structures is addressed in this article using a topology optimization method. Taking into consideration the complexities and wide applications of thin walled stiffened structures in aeronautic and astronautic fields, the article proposes a new geometric background grid (GBG) method suitable for stiffener design with unstructured finite element meshes. On the one hand, the stiffener definition is parameterized by this method using the background grid size. On the other hand, the definition of the background grid in the curvelined coordinate system makes it possible to perform stiffener design of 3D curved shells. To validate the GBG method, it is applied to the stiffness maximization of plane and curved panels. Numerical examples show that this method can provide satisfactory results for stiffener layout.

Key words: stiffener design, thin walled structures, topology optimization, layout optimization, geometric background grid (GBG), stiffness maximization