Oscillatory flame edge propagation, isolated flame tubes and stability in a non-premixed counterflow
نویسندگان
چکیده
An investigation is carried out into the ranges of Damköhler number and Lewis number, less than unity, in which different forms of combustion phenomena arise within a non-premixed counterflow; cases that are symmetrical across the counterflow are chosen for study. These link oscillatory and steady propagation of flame edges, zero propagation speeds, isolated flame tubes, quenching and marginal stability of planar diffusion flames. Over a range of Lewis numbers, the transition between steady and oscillatory propagation of a flame edge has characteristics that are consistent with a subcritical Hopf bifurcation. Isolated flame tubes are found to persist up to a Lewis number that is very close to unity.
منابع مشابه
Edges of flames that don’t exist
A counterflow diffusion flame model is studied revealing that, at least as a part of the quenching boundary is approached in parameter space at low enough Lewis numbers, an edge of a diffusion flame, or triple flame, has a propagation speed that still advances the burning solution into regions that are not burning. In crossing the quenching boundary, the advancing flame edge remains a robust pa...
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