Estudo experimental em túnel de vento subsônico do arrasto e sustentação do demonstrador da combustão supersônica X-43

Abstract

Scramjet technology demonstrators aim to demonstrate aspirated hypersonic propulsion at hypersonic speeds, that is, 5 times the speed of sound at flight altitude. The design of these vehicles aims to adapt to thermal and structural aerodynamic efforts for speeds greater than Mach 5. A scramjet vehicle works only at hypersonic speeds, however, to leave an aerodrome and reach operating speed and altitude the vehicle must be accelerated by another aircraft or other form of propulsion. Therefore, a hypersonic vehicle like the X-43 goes through all stages of flight from rest, going through the subsonic, transonic, and supersonic speed regimes until reaching hypersonic speed. Although projects have a large team of professionals, Scramjet vehicle designers often ignore subsonic stability in projects at hypersonic speeds, but for a viable final project, stability and maneuverability at low (subsonic) speeds are crucial for a well-driven vehicle, given that currently, there are only hypersonic vehicles for military purposes, there are studies predicting vehicles for transporting passengers. Little is known about the aerodynamic behavior of this vehicle in subsonic flight, therefore in this present study an aerodynamic analysis of the drag and lift forces in subsonic flight will be carried out on the geometry of NASA's Scramjet X-43 demonstrator on a scale of 1:3.66 in a closed wind tunnel at a cruising speed of 20 m/s to verify the predictions of this geometry for a stable flight with an angle of attack of 0°, that is, the aircraft axis perpendicular to the airflow.