Date of Award


Document Type


Degree Name

Master of Science in Aeronautical Engineering


Department of Aeronautics and Astronautics

First Advisor

Paul I. King, PhD


Pulse Detonation Engines (PDE) operating on liquid hydrocarbon fuels are limited to operating frequencies of 35 Hz due to long ignition times from a low energy ignition sources. This study shows ignition time of JP-8 can be nearly eliminated by igniting a thrust tube using a secondary detonation. A counter flow heat exchanger attached to a thrust tube utilized waste heat from the detonation process to heat JP-8 to supercritical conditions. The fuel flash vaporized when injected into the air stream of the engine. A detonation was produced by a spark in a 5 cm diameter, 1.37 m long tube. The detonation was then propagated in a 1.9 cm diameter crossover tube into the head of second thrust tube where a pressure transducer and hydroxyl (OH) sensor measured the combustion event. Branch detonation was performed over a range of equivalence ratios ranging from 1.05 to 1.3. Branch ignited thrust tubes have shown 40% improvement in deflagration to detonation transition (DDT) time and a slight improvement in DDT distance.

AFIT Designator


DTIC Accession Number