Hypersonic Aeroelastic and Aerothermoelastic Studies Using Computational Fluid Dynamics

A framework for aerothermoelastic-stability-boundary calculation for hypersonic configurations using computational fluid dynamics combined with radial basis functions for mesh deformation is developed. Application of computational fluid dynamics enables one to consider different turbulence conditions, laminar or turbulent, and different models of the air mixture, in particular real-gas model, which accounts for dissociation of molecules at high temperature. The effect of transition on the flutter margin of the heated structure is also considered using an uncertainty-propagation framework. The aerothermoelastic-stability margin of a three-dimensional low-aspect-ratio wing, representative of a control surface of a hypersonic vehicle, is investigated for various flight conditions. The system is found to be sensitive to turbulence modeling, as well as the location of the transition from laminar to turbulent flow. Real-gas effects play a minor role for the flight conditions considered. This study demonstrates the advantages of accounting for uncertainty at an early stage of the analysis, and emphasizes the important relation between transition from laminar to turbulent, thermal stresses, and stability margins of hypersonic vehicles.