Structural Design and Optimisation of the LAPCAT A2 Mach 5 Vehicle Based on Aero-Elastic Deformations

摘要

Structural design of hypersonic aircraft is severely impacted by the high temperatures encountered during flight as they can lead to high thermal stresses and a significant reduction in material strength and stiffness. This reduction in structural rigidity requires innovative concepts and a stronger focus on aeroelastic deformations in the design and optimisation of the aircraft structure. This imposes the need for a closer coupling of the aerodynamic and structural tools than is current practise. The current paper presents how the different sizing, analysis, design and optimisation tools are coupled in the design of the structure for the LAPCAT A2 vehicle and gives results of the optimisation of a hot structure for the wing. The results indicate that skin buckling is the main driver for the wing structural weight regardless of the number of spars and ribs used. A wing structure with 6 spars and 6 ribs with cross-grid stiffeners leads to the lightest solution, weighing in just under 20 tons. Uni-axial stiffened skin concepts are considerably heavier.