On the Double-Double Laminate Buckling Optimum for the 18-Panel ‘Horse-Shoe’ Reference Case

Abstract

The Double-Double (DD) laminate family allows for simplification in the context of buckling analysis. Stacking-sequence discussions, known from conventional-laminate optimization, made from 0∘, ±45∘, 90∘ plies, omit for DD. The recently presented DD-specific buckling relation is applied in this article to the 18-panel, ‘horse-shoe’ laminate blending reference case. The use case addresses the challenge of identifying a compatible group of laminates for differently loaded, adjacent regions, as it is a common scenario in wing covers and fuselage skins. The study demonstrates how the novel DD-laminate buckling relation simplifies the process of determining a buckling optimum for a group of laminates. The process of determining the optimum blended DD panel is presented. Its determined mass is compared with minimum masses, presented in earlier studies, which focus on stacking optimization and blending for more conventional ply orientations and laminate stacking conventions.