Flame acceleration and DDT of hydrogen-oxygen gaseous mixtures in channels with no-slip walls
2011 (English)In: International journal of hydrogen energy, ISSN 0360-3199, Vol. 36, no 13, 7714-7727 p.Article in journal (Refereed) Published
Hydrogen-oxygen flame acceleration and transition from deflagration to detonation (DDT) in channels with no-slip walls were studied theoretically and using high resolution simulations of 2D reactive Navier-Stokes equations, including the effects of viscosity, thermal conduction, molecular diffusion, real equation of state and a detailed chemical reaction mechanism. It is shown that in "wide" channels (D > 1 mm) there are three distinctive stages of the combustion wave propagation: the initial short stage of exponential acceleration; the second stage of slower flame acceleration; the third stage of the actual transition to detonation. In a thin channel (D < 1 mm) the flame exponential acceleration is not bounded till the transition to detonation. While velocity of the steady detonation waves formed in wider channels (10, 5, 3, 2 mm) is close to the Chapman Jouguet velocity, the oscillating detonation waves with velocities slightly below the CJ velocity are formed in thinner channels (D < 1.0 mm). We analyse applicability of the gradient mechanism of detonation ignition for a detailed chemical reaction model to be a mechanism of the deflagration-to-detonation transition. The results of high resolution simulations are fully consistent with experimental observations of flame acceleration and DDT in hydrogen-oxygen gaseous mixtures.
Place, publisher, year, edition, pages
2011. Vol. 36, no 13, 7714-7727 p.
Hydrogen, Flame acceleration, Shock wave, DDT, Detonation
IdentifiersURN: urn:nbn:se:uu:diva-156107DOI: 10.1016/j.ijhydene.2011.03.134ISI: 000292123900041OAI: oai:DiVA.org:uu-156107DiVA: diva2:430542