TY - JOUR
T1 - Hydrodynamic and diffusion effects on the stability of spherically expanding flames
AU - Bechtold, J. K.
AU - Matalon, M.
N1 - Funding Information:
* This work was supportedin part by the NationalS cience Foundatiounn derg rantsC BT-8521352an dD MS-8601903an d by the U.S. Departmenotf Energy under grant DE-AC02-78ER04650.
Copyright:
Copyright 2014 Elsevier B.V., All rights reserved.
PY - 1987/1
Y1 - 1987/1
N2 - We examine the stability of an outwardly propagating spherical flame accounting for both hydrodynamic and thermodiffusive effects. For Lewis numbers less than a critical value Le* < 1, disturbances of the flame front grow during the initial phase of propagation, i.e., when the radius is comparable to the flame thickness. However, for Le > Le*, the flame, which is stable to thermodiffusive effects, becomes unstable only after a critical size is reached. This instability is hydrodynamic in nature and is caused by the thermal expansion of the gas. In this study we provide an expression for the determination of the critical size, or a critical Peclet number, which depends on the thermal expansion coefficient and on the Lewis number. The explicit dependence on all the relevant physicochemical parameters enables us to compare our results with experimental data.
AB - We examine the stability of an outwardly propagating spherical flame accounting for both hydrodynamic and thermodiffusive effects. For Lewis numbers less than a critical value Le* < 1, disturbances of the flame front grow during the initial phase of propagation, i.e., when the radius is comparable to the flame thickness. However, for Le > Le*, the flame, which is stable to thermodiffusive effects, becomes unstable only after a critical size is reached. This instability is hydrodynamic in nature and is caused by the thermal expansion of the gas. In this study we provide an expression for the determination of the critical size, or a critical Peclet number, which depends on the thermal expansion coefficient and on the Lewis number. The explicit dependence on all the relevant physicochemical parameters enables us to compare our results with experimental data.
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U2 - 10.1016/0010-2180(87)90015-0
DO - 10.1016/0010-2180(87)90015-0
M3 - Article
AN - SCOPUS:0023089496
SN - 0010-2180
VL - 67
SP - 77
EP - 90
JO - Combustion and Flame
JF - Combustion and Flame
IS - 1
ER -