Gas-phase transient diffusion in droplet ignition

B. H. Chao, M. Matalon, C. K. Law

Research output: Contribution to journalArticle

Abstract

The existing droplet ignition criterion was obtained by examining the initiation of chemical reaction in the far field under the assumption of gas-phase quasi-steadiness. However, it is precisely in this far field where transient diffusion becomes important. In order to incorporate this effect in an ignition analysis, we consider the simultaneous limits of a small gas-to-liquid density ratio and a large activation energy of the chemical reaction. The ignition dynamics is thus investigated; in particular, ignition delay times and ignitability criteria are obtained. Comparison of the ignition Damköhler number obtained in the present study with that corresponding to the quasi-steady case shows that they may differ significantly, hence demonstrating the qualitative importance of transient diffusion in droplet ignition.

Original languageEnglish (US)
Pages (from-to)43-51
Number of pages9
JournalCombustion and Flame
Volume59
Issue number1
DOIs
StatePublished - Jan 1985

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ignition
Ignition
Gases
vapor phases
far fields
Chemical reactions
chemical reactions
Density of liquids
Time delay
time lag
Activation energy
activation energy
liquids
gases

ASJC Scopus subject areas

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

Cite this

Gas-phase transient diffusion in droplet ignition. / Chao, B. H.; Matalon, M.; Law, C. K.

In: Combustion and Flame, Vol. 59, No. 1, 01.1985, p. 43-51.

Research output: Contribution to journalArticle

Chao, B. H. ; Matalon, M. ; Law, C. K. / Gas-phase transient diffusion in droplet ignition. In: Combustion and Flame. 1985 ; Vol. 59, No. 1. pp. 43-51.
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