Hydrodynamic and diffusion effects on the stability of spherically expanding flames

J. K. Bechtold, M. Matalon

Research output: Contribution to journalArticle

Abstract

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.

Original languageEnglish (US)
Pages (from-to)77-90
Number of pages14
JournalCombustion and Flame
Volume67
Issue number1
DOIs
StatePublished - Jan 1987

Fingerprint

Lewis numbers
Thermal expansion
flames
thermal expansion
Hydrodynamics
hydrodynamics
Peclet number
Gases
coefficients
gases

ASJC Scopus subject areas

  • Chemistry(all)
  • Chemical Engineering(all)
  • Fuel Technology
  • Energy Engineering and Power Technology
  • Physics and Astronomy(all)

Cite this

Hydrodynamic and diffusion effects on the stability of spherically expanding flames. / Bechtold, J. K.; Matalon, M.

In: Combustion and Flame, Vol. 67, No. 1, 01.1987, p. 77-90.

Research output: Contribution to journalArticle

@article{0ab4470f71e4481797d7b64d120e9f7a,
title = "Hydrodynamic and diffusion effects on the stability of spherically expanding flames",
abstract = "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.",
author = "Bechtold, {J. K.} and M. Matalon",
year = "1987",
month = "1",
doi = "10.1016/0010-2180(87)90015-0",
language = "English (US)",
volume = "67",
pages = "77--90",
journal = "Combustion and Flame",
issn = "0010-2180",
publisher = "Elsevier Inc.",
number = "1",

}

TY - JOUR

T1 - Hydrodynamic and diffusion effects on the stability of spherically expanding flames

AU - Bechtold, J. K.

AU - Matalon, M.

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.

UR - http://www.scopus.com/inward/record.url?scp=0023089496&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0023089496&partnerID=8YFLogxK

U2 - 10.1016/0010-2180(87)90015-0

DO - 10.1016/0010-2180(87)90015-0

M3 - Article

AN - SCOPUS:0023089496

VL - 67

SP - 77

EP - 90

JO - Combustion and Flame

JF - Combustion and Flame

SN - 0010-2180

IS - 1

ER -