Shock-Wave Mechanism of Detonation Initiation in Premixed Hydrogen-Argon-Oxygen Flow Around a Fast-Flying Body
I. A. Bedarev
Khristianovich Institute of Theoretical and Applied Mechanics, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia
Keywords: multifront detonation, detonation initiation, numerical modeling, detonation initiation energy
Abstract
A computational method has been developed to model the shock-wave mechanism of detonation wave initiation during the interaction of a fast flying body (FFB) with a combustible hydrogen-oxygen mixture diluted with 50% argon under normal conditions. The FFB velocities at Mach numbers M = 3-4 are considered, which are lower than the Chapman-Jouguet detonation velocity in the mixture under study at normal pressure and temperature. It is shown that the detonation wave is initiated at a FFB velocity exceeding M = 3.9. In this case, the shock-wave mechanism of detonation initiation occurs where a detonation wave is formed at the shock wave separated from the combustion wave by an induction zone. The modeling identified a new regime of reaction gas flow around the FFB. In the range of FFB velocities M = 3.4-3.85, a quasi-stationary mode of shock-initiated combustion occurs. The flow parameters required for direct initiation of multifront detonation of the FFB are consistent with analytical estimates of the initiation energy.
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