Effects of Increasing Aerothermodynamic Fidelity on Hypersonic Trajectory Optimisation for Flight Testing Purposes

Abstract

In a previous study, the optimal re-entry trajectory of Hyperion-2 has been derived. The mission of the vehicle is to measure hypersonic boundary-layer transition, a phenomena in which the laminar boundary layer turns into a turbulent boundary layer. This is an important feature in hypersonic flow to investigate, as it introduces peak heating and increases drag. A constant Mach 10 flight has been performed, optimising for flight time, whilst maintaining a large Reynolds number range, in which transition occurs (Retrans = 106). Hyperion-2 is a theoretical experimental vehicle studied at Delft University of Technology. The aerodynamic coefficients of Hyperion-2 in the previous study have been obtained using a modified Newtonian panel method. In present thesis, the aerodynamic coefficients are computed using an open source computational fluid dynamics software called SU2 (Stanford University Unstructured). Simple geometries have been used to verify and validate the solver, focusing on shock position and shape, pressure distribution and heat flux. Using an open source mesh generator called GMSH, a three dimensional unstructured grid of Hyperion-2 has been generated. With this grid, the aerodynamic database consisting of 120 combinations of Mach number and angles of attack has been created. The database has been used to create a new optimal trajectory for the Hyperion-2 mission. During the presentation, the differences in aerodynamic coefficients are evaluated and the effect on the optimal constant Mach 10 flight trajectory is presented.