Effects of Aerothermal Shape Distortion on Hypersonic Vehicle Performance in Cruise

Abstract

This paper explores the effects of aerothermal shape distortion upon the aerodynamic  performance of a hypersonic vehicle. A reference waverider vehicle was designed to operate at a nominal cruise condition of Mach 7 at 39 km altitude. A simple semi-monocoque structure made from titanium alloy skins and frames is used with constant skin thicknesses and a solid tungsten nose ballast. The aerodynamic performance of the vehicle was assessed using Ansys Fluent with the Spalart-Allmaras turbulence model. Multiphysics aerothermal distortion was computed using a two-way steady state coupled approach with linearly interpolated temperatures. This resulted in an increase in maximum drag of 14.8% and a decrease in the maximum lift-to-drag ratio of 4.76%. Significant changes in the stability of the vehicle were also observed at higher angles of attack.