Schlieren Imaging of a Single-Ejector, Multi-Tube Pulsed Detonation Engine (Postprint)

Single-ejector, multi-tube pulsed detonation engine configurations are examined utilizing high speed Schlieren and coherent structural velocimetry. The mechanisms of ejector augmentation are evident in secondary air entrainment and induced flow across the ejector lip. An axisymmetric ejector with both a linear array and a more compact box array of detonation tubes was examined. Good secondary entrainment and subsequent ejector flow was observed, supporting previous results indicating off-axis effects are relatively insignificant to ejector thrust augmentation. A linear ejector with linear detonation tubes revealed limited secondary flow engagement with the ejector lip, likely due to structural ribs.