High Temperature Effects On Aerothermodynamics Of Complicated Shape Aircraft

Regarding hypersonic vehicles, extremely high temperature will be induced according to the hypersonic aerodynamics, which may change the characteristics of its surrounding air, known as the high-temperature effects, and thus influence the aero thermodynamic performance of the vehicle. In order to more precisely predict the aerodynamics and aerothermodynamics of hypersonic vehicles, and to improve the stability and the controlling accuracy, a research on impact of high temperature effects on aerothermodynamics of complicated shape aircraft was conducted.Referring to regimes of air thermal and chemical state at different flight velocities and altitudes, this research is based on our team’s calorically perfect gas model and the 5 components/5 reactions chemical kinetic mechanisms. AUSMPW+ spatial scheme and the implicit LUSGS temporal scheme are also employed to solve the three dimensional Naiver-Stokes equations. With consideration of the super catalytic and non-catalytic wall boundary conditions, a code named HyCFD for the simulation of hypersonic high-temperature flow fields has been completed. Approaches in this research are proved feasible and reliable, by numerical validation and verification with several classic hypersonic high-temperature benchmark testing cases.Concentrating on the vehicles with all-movable rudder in long span flight conditions with diverse flight attitudes, this research discussed the key factors influencing the aerothermodynamic performance of hypersonic vehicles by the high-temperature effects, and the influential disciplines of the high-temperature effects upon the aerothermodymanic performance of hypersonic vehicles.The research indicated that: high-temperature effects are mainly due to speed and altitude of the hypersonic vehicle. High-temperature effects make the outstanding distance of shock wave short, reduce the surface temperature sharply as well as the heat flux; however, they have trivial influence on the near-wall distributions of both velocity and pressure. The surface catalytic condition majorly influences the heat flux, then the local near-wall shearing stresses, and at last the global aerodynamics on a very low level. High-temperature effects also reduce the lift and drag efficiencies, lower the efficiency of rudder, and produce nose up pitching moment by moving the center of pressure forward.High-temperature effects are common for hypersonic flights; therefore, this research on the high-temperature effects processes great significance for the fast, precise and safe design of hypersonic vehicles.