Hypersonic retro propulsion for reusable launch vehicles tested in the H2K wind tunnel

Abstract In the frame of RETALT (RETro propulsion Assisted Landing Technologies) project, aerodynamics reusable launch vehicles reentering atmosphere and descending landing with aid retro are studied. particular, series wind tunnel tests performed to assess aerodynamic properties such a vehicle in various flight phases from hypersonic supersonic re-entry down subsonic conditions at touch down. This paper discusses results Hypersonic Wind Tunnel Cologne (H2K) Supersonic Flow Technologies Department German Aerospace Center (DLR) for maneuver during burn. Mach numbers 5.3 7.0 were tested variation thrust coefficient, Reynolds number, angle attack, cold heated air. A single-engine configuration three active engines tested. all tests, engine exhaust was simulated using ambient temperature or Dependencies flow features square root coefficient known literature case can be confirmed extended three-engine configuration. For case, formation vortex rings observed, which eventually leads strong individual vortices extensive field disturbances. The heating supply air up 600 K mitigates condensation plume, while overall structures remained unchanged. High coefficients generally lead vanishing pressure on bay. single cases comparable this sense. number subordinate importance pressures vehicle, is dominating similarity parameter. Pressure far downstream plume affected less and, therefore, not negligible non-zero angles attack. paper, methodology obtained described detail.