Time-Resolved Particle Image Velocimetry was used to study transient interactions between hydrogen-enriched methane/air premixed flames and toroidal vortex structures. Lean and stoichiometric mixtures with hydrogen mole fraction in the fuel (hydrogen plus methane), xH 2, varying in the range of 0-0.5 were investigated. Results have shown that the hydrogen presence affects the flow field both quantitatively (increase of the velocity of the main toroidal vortex) and qualitatively (generation of different sub-vortices within the main vortex), enhancing the intensity of the interaction. Regardless of the mixture stoichiometry, the hydrogen substitution to methane leads to a transition from a regime in which the vortex only wrinkles the flame front (xH 2<0.2) to a more vigorous regime in which the interaction almost results in the separation of small flame pockets from the main front (xH 2>0.2). This transition was characterised in terms of time histories of flame surface area and burning rate. Copyright © 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.
Time-Resolved Particle Image Velocimetry of dynamic interactions between hydrogen-enriched methane/air premixed flames and toroidal vortex structures / V., Di Sarli; DI BENEDETTO, Almerinda; E., Long; G., Hargrave. - In: INTERNATIONAL JOURNAL OF HYDROGEN ENERGY. - ISSN 1879-3487. - 37:(2012), pp. 16201-16213. [10.1016/j.ijhydene.2012.08.061]
Time-Resolved Particle Image Velocimetry of dynamic interactions between hydrogen-enriched methane/air premixed flames and toroidal vortex structures
DI BENEDETTO, ALMERINDA;
2012
Abstract
Time-Resolved Particle Image Velocimetry was used to study transient interactions between hydrogen-enriched methane/air premixed flames and toroidal vortex structures. Lean and stoichiometric mixtures with hydrogen mole fraction in the fuel (hydrogen plus methane), xH 2, varying in the range of 0-0.5 were investigated. Results have shown that the hydrogen presence affects the flow field both quantitatively (increase of the velocity of the main toroidal vortex) and qualitatively (generation of different sub-vortices within the main vortex), enhancing the intensity of the interaction. Regardless of the mixture stoichiometry, the hydrogen substitution to methane leads to a transition from a regime in which the vortex only wrinkles the flame front (xH 2<0.2) to a more vigorous regime in which the interaction almost results in the separation of small flame pockets from the main front (xH 2>0.2). This transition was characterised in terms of time histories of flame surface area and burning rate. Copyright © 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.