Reinitiation phenomenon in hydrogen-air rotating detonation engine.

This article presents a numerical study on the rotating detonation engine (RDE). The simulation explores the phenomenon of the reinitiation of detonations in the RDE with a cylindrical combustion chamber. The process is modelled by the three-dimensional reactive Euler equations with an Arrhenius form of the reaction rate for the premixed stoichiometric hydrogen-air mixture. The detonation flow goes through three stages: initiation, quenching, and spontaneous reinitiation. The detonation fronts collide with each other and also have frequent collisions with the outer wall after initiation. While there is a possibility of generating new detonation fronts from the explosion, it is also likely that the explosion will burn out the surrounding reactive mixtures and snuff out the detonation waves. The simulation shows that a strong collision between two detonation wave fronts extinguishes the detonation flow and consequently renders the engine inoperative for an extended period until a spontaneous reinitiation occurs in the flow. The reinitiation is found to be triggered by a rapid and sharp increase of pressure near the chamber wall. [ABSTRACT FROM AUTHOR]