Liftoff height of turbulent diffusion flame in water-mist-laden coflowing air stream
نویسندگان
چکیده
In the present study, enhancement of liftoff and blowout a propane/air coflowing diffusion flame by water mist was experimentally investigated in subsonic range. When fuel injection velocity U f is low, an attached laminar stabilized at burner rim with premixed base. An increase leads to flame, eventually lifted flame. The upstream disappears turbulent downstream region. stability deteriorates air flow rate Q m . stable can be achieved dynamic balance local mean gas g ¯ propagation speed p formed base estimated measurements laser Doppler velocimeter. decreases order 1 m/s independently mass fraction Y 0 This value nearly equal 2.5 S L , where adiabatic stoichiometric propane-air mixture. height increases both For case without mist, unique correlation has been proposed previous studies between non-dimensional form using By extending this water-mist-laden stream, influenced appraised compared simulation previously reported. Resulting reduction 65% that predicted numerical simulation, presumably due partial evaporation mist.
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ژورنال
عنوان ژورنال: Combustion and Flame
سال: 2021
ISSN: ['1556-2921', '0010-2180']
DOI: https://doi.org/10.1016/j.combustflame.2021.111425