Planar Detonation Wave Initiation in Large-Aspect-Ratio Channels
In this study, two initiator designs are presented that are able to form planar detonations with low input energy in large-aspect-ratio channels over distances corresponding to only a few channel heights. The initiators use a single spark and an array of small channels to shape the detonation wave. The first design, referred to as the static initiator, is simple to construct as it consists of straight channels which connect at right angles. However, it is only able to create planar waves using mixtures that can reliably detonate in its small-width channels. An improved design, referred to as the dynamic initiator, is capable of detonating insensitive mixtures using an oxyacetylene gas slug injected into the initiator shortly before ignition, but is more complex to construct. The two versions are presented next, including an overview of their design and operation. Design drawings of each initiator are available elsewhere . Finally, photographs and pressure traces of the resulting planar waves generated by each device are shown.
© 2006 by California Institute of Technology. Published by the American Institute of Aeronautics and Astronautics, Inc., with permission. Received 5 December 2005; revision received 5 May 2006; accepted for publication 5 May 2006. This work was sponsored by the Department of Defense and Army Research Office through a National Defense Science and Engineering Graduate (NDSEG) Fellowship, by the Office of Naval Research Grants, "Pulse Detonation Engines: Initiation, Propagation and Performance," "Multidisciplinary Study of Pulse Detonation Engine," and "Detonation Initiation by Annular Jets and Shock Waves," and by General Electric. The authors are grateful for the assistance of M. Grunthaner and F. Pintgen.
Published - JACaiaaj06.pdf