Development and testing of a miniature pulse detonation engine

The purpose of the present work was to develop a new design of the Pulse Detonation Engine (PDE). The weight of the PDE is a prime factor to be considered when the engine is to be used for propulsive applications. Previous research into pulse detonation conducted in UTA used a 3 in. (76 mm) internal diameter detonation tube. The goal of the new design was to reduce the weight and size of the engine. The new design resulted in a detonation tube of ¾ in. (19 mm) internal diameter thus reducing the weight of the engine. The PDE consists of a detonation tube one end of which is open to the atmosphere while the other end is closed. A near stoichiometric mixture of propane and oxygen were used as reactants. Air was used for purging the combustion products. A high voltage arc igniter was used to initiate combustion. Preliminary tests were conducted for cycle frequencies of 5, 10 and 20 Hz for mixtures initially at 1 atm. A bare tube and one with a segment that had a Shchelkin spiral were tested. It was found that the velocities of the combustion wave were closer to the Chapman-Jouguet (CJ) velocity when the Shchelkin spiral was used as compared to the velocities achieved in the bare detonation tube.