Wave Drag Reduction Approach for Blunt Bodies at High Angles of Attack: Proof-of-Concept Experiments

Abstract

The present investigation is an attempt to improve the aerodynamic effectiveness of aero-spikes located at the nose of supersonic blunt bodies flying at a wide range of angles of attack. For this purpose, the use of pivoting spikes, which can maintain their favorable alignment relative to the incoming flow independent from the body's orientation, is proposed. The proof-of-concept experiments for the pivoting spikes have been conducted in the Ludwieg Tube Facility at DLR Göttingen at Mach 2, 3 and 5 for angles of attack from 0 to 30 degrees. The model tested is a cylindrical body with a hemispherical nose. Additionally to the body equipped with a pivoting spike the reference body without a spike and the body with a conventional fixed spike were investigated. The results containing shadowgraph visualizations, direct force measurements and infrared heat flux measurements show the clear adventages of the pivoting spikes.