The relevance of reliability-based topology optimization in early design stages of aircraft structures

Abstract

This paper aims to compare the structural designs derived from Deterministic Topology Optimization (DTO) and Reliability-Based Topology Optimization (RBTO). The target is to prove that including uncertain data in preliminary stages of the design process such as topology optimization can help to reduce the weight of the component to be conceived. To compare both approaches the same Reliability-Based Design Optimization (RBDO) sizing problem is formulated over the bar structures emerged from the DTO and RBTO results. The RBTO is performed through the RBDO algorithm Sequential Optimization and Reliability Assessment (SORA) based on its robustness, accuracy and decoupled nature, which allows to use an external optimization software when dealing with the topology optimization problem. Three application examples, including two 2D bar structures and a 3D simplified aircraft rear fuselage are studied. The results show that the designs based on RBTO are lighter than the designs based on DTO when both structures are compared in a subsequent reliability-based size optimization including the same probabilistic information.