Challenges of using topology optimization for the design of pressurized stiffened panels

Topology optimization has been successfully used in several case studies in aerospace and automotive industries to generate innovative design concepts that lead to weight savings. This motivates the exploration of this new approach for the design of an aircraft flat pressure bulkhead. However, no studies were conducted on this type of structure. Therefore, this paper presents and discusses the challenges associated with the design of flat pressurized plate using topology optimization (SIMP (Solid Isotropic Material with Penalization) method). A simply supported rectangular plate is used as the design case and a typical layout is defined as a comparison basis. The mass of the interpreted design concepts are obtained with a simplified sizing approach taking into consideration stress and displacement constraints. Results show that the topology layout is not unique as is sensitive to optimization parameters. Moreover, the interpretation of the layout is challenging as they are driven by complex interactions. Finally, the performance of the topology design concept is at most comparable with the typical layout and no significant improvement is obtained. The study highlights the importance of performing an extensive topology study in order to better understand the behavior of the design before creating a concept. An improved topology design process is finally proposed in order to provide guidance to industrial designers.