Abstract
The Saffman-Taylor (S-T) instability mechanism in laminar premixed flames in a Hele-Shaw cell is investigated using two-dimensional numerical simulations with an Arrhenius reaction model and Poiseuille assumption for the viscous effect. The baseline calculations considering the Darrieus-Landau (D-L) and diffusive-thermal instability modes show results consistent with the classical linear instability theory. The primary effect of the variable transport properties is found to be the modification of the flame thickness, such that the results can be properly normalized by the actual flame thickness and timescales. The effect of different Lewis numbers is also found to be consistent with previous studies. With the S-T instability mechanism, the overall effect is to enhance the destabilizing mechanism by providing an increased viscous force in the product gas. The linear instability behaviour is found to be qualitatively similar to the D-L mechanism. However, the results in the nonlinear range demonstrate that there may exist distinct characteristic timescales associated with D-L and S-T mechanisms, such that the latter effect sustains longer in time, contributing to a higher overall flame speed. The calculations show that the S-T effect is considerable for Peclet numbers less than 50. For sufficiently smaller Peclet numbers, the overall flame speed is found to be significantly affected by the S-T mechanism.
Original language | English (US) |
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Pages (from-to) | 343-363 |
Number of pages | 21 |
Journal | Combustion Theory and Modelling |
Volume | 7 |
Issue number | 2 |
DOIs | |
State | Published - Jun 2003 |
Externally published | Yes |
Bibliographical note
Funding Information:This work was undertaken as a joint research programme initiated by the Institute of BK 21 Mechanical Engineering at the Korea Advanced Institute of Science and Technology (KAIST), Korea. HGI was also partly supported by the National Science Foundation under the monitoring of Dr Farley Fisher. SWB was supported by the Korea Agency of Defense Development and the Center for ElectroOptics at KAIST. The authors would like to thank Professor Paul D Ronney of University of Southern California for motivating this paper and providing many helpful comments.
ASJC Scopus subject areas
- General Chemistry
- General Chemical Engineering
- Modeling and Simulation
- Fuel Technology
- Energy Engineering and Power Technology
- General Physics and Astronomy