Quantitative Analysis of Flame Instabilities in a Hele-Shaw Burner

Abstract

We show in this paper that a Hele-Shaw burner can be used for studying the development of premixed flame instabilities in a quasi-two dimensional configuration. It is possible to ignite a plane flame at the top of the cell, and to measure quantitatively the growth rates of the instability by image analysis. Experiments are performed with propane and methane-air mixtures. It is found that the most unstable wavelength, and the maximum linear growth rate of perturbations, directly measured in the present experiments, have the same order of magnitude as those previously measured on flames propagating freely downwards in wide tubes.

Darrieus–Landau instability and Markstein numbers of premixed flames in a Hele-Shaw cell

“…Our experiments show a net increase of the flame propagation velocity, except for lean flames, and the effects on the instability appears to be reduced just to quantitative modifications (ca. 30% reduction on the growth rates, see [7]). This could…”

“…The experiment, which will be described in more 1 * Corresponding author email bruno.denet@irphe.univ-mrs.fr detail in [7], is summarized here: the Hele-Shaw burner consists of two glass plates 50 cm wide and 150 cm high, separated by a gap width of 4.7 mm. It is mounted vertically with the inlet gas mixture 25 at the bottom, open at the upper end.…”

“…The effective experimental expansion ratio E = 7.3 for φ = 1.0 can be compared to the value obtained by Cantera with a San Diego mechanism E = 7.95. Unfortunately we were 205 not able to measure growth rates for rich propane flames, as explained in [7] (because of difficulties to anchor the flame for slightly rich flames, or Bunsen flame already cellular for very rich flames). In the methane case (figure 6), the accessible 210 range of equivalence ratio was larger, from φ = 0.9 to φ = 1.3.…”

Experimental and numerical Lattice-Boltzmann investigation of the Darrieus–Landau instability

“…vertically oriented and separated by a ∆ = 5mm gap, shown in laser-cut with a sinusoidal profile, is positioned at top of the burner next to the anchored flame (see [21] for details about the experimental technique).…”

Coupling of vibro-acoustic waves with premixed flame

“…More recently, accurate studies of the Darrieus-Landau wrinkling have been performed in an experimental device which allows to reduce the flame dynamics to a quasi-bidimensionnal one [18,[23][24][25][26][27][28][29]. The two dimensional dynamics has been shown to be similar to that of freely propagating flames [18].…”