Application of an Innovative Design Approach to an Aircraft Frame Using Double-Double Laminates

Abstract

This work includes the presentation and application of the innovative Double-Double design approach. Key enablers of the method, such as homogenization of DD laminates and the approach to design thickness changes within a component, are explained. In addition, a failure criterion for fiber composites, based on introducing a principal strain cutoff circle, is presented. The work focuses on applying the double-double layup method, including the tapering strategy, to an integral aircraft frame. For this purpose, the existing finite element model of the frame is altered. The DD angles Φ and Ψ are determined based on various criteria. In this context, an optimization problem is defined using an interface between Abaqus and Python. The resulting frame configurations are evaluated in terms of weight and structural performance. In addition, current design guidelines for fiber composites are presented and compared with the DD philosophy.