Enhanced Mixing in Supersonic Flow Using a Pulse Detonator

Mixing enhancement in a M = 2 crossflow using the transient high-pressure, high-temperature, and high-velocity pulse from a detonation was investigated experimentally. High-frame-rate shadowgraphy and planar laser-induced fluorescence of the nitric oxide molecule showed the structure and time-dependent interaction of the detonation plume with the supersonic flow. The high-momentum flux from the detonation provided significant penetration, with blowdown times of 4-8 ms achieved. Planar laser-induced fluorescence of nitric oxide captured the spanwise structure of the plume and the large counter-rotating vortex structure for enhanced mixing. The upstream jet was shown to be drawn into the pulse detonator's plume, providing distribution to the core supersonic flow. Significant coupling between a continuous upstream jet and the pulse detonator plume was found and indicated that there was an optimal staging distance for enhanced mixing.