Experimental investigation of the limits of ethanol combustion in the
boundary layer behind an obstacle
B.F.
Boyarshinov
Kutateladze Institute of Thermophysics SB RAS,
Novosibirsk, Russia
E-mail: boyar@itp.nsc.ru
Keywords: flame blow-off, mixed convection, combustion “on the ceiling”, PIV method, Rayleigh-Taylor instability, mushroom-like structures
Abstract
Experimental data on the
flow structure and mass transfer near the boundaries of the region existence of
the laminar and turbulent boundary layers with combustion are considered.
These data include the results of investigation on reacting flow stability at
mixed convection, mass transfer during ethanol evaporation “on the floor” and
“on the ceiling”, when the flame surface curves to form the large-scale
cellular structures. It is shown with the help of the PIV equipment that
when Rayleigh–Taylor instability manifests, the mushroom-like structures are
formed, where the motion from the flame front to the wall and back alternates.
The cellular flame exists in a narrow range of velocities from 0.55 to 0.65
m/s, and mass transfer is three times higher than its level in the standard
laminar boundary layer.
DOI: 10.1134/S0869864318010043
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