Effects of a jet turbulator upon flame acceleration in a detonation tube

Abstract

Allowing a fuel/air mixture to flow through bluff-body structures enhances the deflagration-to-detonation transition (DDT) process in pulse-detonation engines by increasing the turbulence intensity within the detonation chamber. However, these structures give rise to resistance and thrust loss. The use of jets as turbulators to reduce the obstacle-blockage ratio may reduce this loss. A jet turbulator composed of multiple evenly spaced jets on the tube wall was designed, and its effects upon flame acceleration were analysed. The results show that fuel/air-mixture jets combined with a low obstacle-blockage ratio can accelerate flame propagation whereas pure-air jets cannot. The jet turbulator offers an improvement over bluff-body structures in terms of acceleration of the DDT process.