ISSN Online: 2377-424X
ISBN Print: 0-89116-299-2
International Heat Transfer Conference 7
BOUNDARY LAYER IGNITION FOR LARGE ACTIVATION ENERGIES WITH FINITE PLATE THICKNESS
要約
An analysis is performed of the influence of the plate thermal resistance on the boundary layer thermal ignition of a premixed combustible gas for the case of large activation energy. The analysis makes use of the boundary layer approximation to describe the gas flow and of first order matched asymptotic expansions to define ignition. Explicit expressions are derived for the critical Damkohler number for ignition and for the ignition distance. It is shown that these variables depend on a non-dimensional
parameter that includes the plate and
gas thermal resistances (Biot number) and the
local Damkohler number. The magnitude of the
ignition variables increases with this parameter.
Comparison of the results for high and low
activation energies shows that their magnitude
affects not only the location of ignition but the
relative position of the adiabatic and ignition
points.