Development and Investigation of an Air-Breathing, Pulse Detonation Engine-Crossover System

Abstract

An air-breathing PDE-crossover system is developed to characterize the effect of shock-initiated combustion within an air-breathing PDE. A shockwave is transferred through a crossover tube that connects a spark-ignited, driver PDE to the air-breathing, driven PDE. Detonations in the driven PDE develop from shock-initiated-combustion caused by shockwave reflection. A PDE-crossover system increases system efficiency through decreased deflagration-to-detonation transition (DDT) time while employing a single spark source to initiate a multi-PDE system. Shock-initiated combustion is researched to evaluate initiation effectiveness in comparison to spark discharge initiation and detonation injection through a predetonator. Increasing Reynolds number enhances combustion wave acceleration. However, the system requires a DDT device to transition the combustion wave to a detonation, for all initiation methods. Shock-initiated combustion and predetonator initiation produce similar results. With an incident shockwave Mach number of MS = 2.36, DDT run-up length is decreased by up to 59.1% compared to the spark discharge method. Similar combustion evolution is observed for an incident shockwave of strength MS = 1.87.