Initiation of diffusion combustion in a supersonic flow of H2–air mixture by electrical-discharge-excited oxygen molecules**This paper was presented at the Third International Symposium on Nonequilibrium Processes, Combustion, and Atmospheric Phenomena (Dagomys, Sochi, Russia, 25–29 June 2007).

Abstract

The methodology of arranging a stable combustion in a diffusion mode in a supersonic non-premixed H2–air flow at a short distance and at a low air temperature due to excitation of O2 molecules to the a 1Δg and states in the electrical discharge is considered. It is shown that for initiation of combustion in this case, it is sufficient to subject the oxygen molecules to an electrical discharge in a thin (with a thickness of 0.5–1 cm) layer located between hydrogen and air streams. It is shown that the mechanism of combustion enhancement is caused by accelerating the chain reactions due to the abundance of excited oxygen molecules in a shear layer and has a non-thermal character.