Effect of vorticity flip-over on the premixed flame structure: Experimental observation of type-I inflection flamesстатья
Статья опубликована в высокорейтинговом журнале
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Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 26 января 2016 г.
Аннотация:Premixed flames propagating in horizontal tubes are observed to take on a convex shape towards the fresh mixture, which is commonly explained as a buoyancy effect. A recent rigorous analysis has shown, on the contrary, that this process is driven by the balance of vorticity generated by a curved flame front with the baroclinic vorticity, and predicted existence of a regime in which the leading edge of the flame front is concave. We report experimental realization of this regime. Our experiments on ethane and n-butane mixtures with air show that flames with an inflection point on the front are regularly produced in lean mixtures, provided that a sufficiently weak ignition is used. The observed flame shape perfectly agrees with that theoretically predicted.