Experimental studies of instabilities of laminar premixed flames

Abstract

We first briefly recall the basic mechanisms controlling the hydrodynamic and thermo-diffusive stability of planar laminar premixed flames, and give the state of the theoretical analysis. We then describe some novel experiments to observe and measure the growth rate of cellular structures on initially planar flames. The first experiment concerns the observation of the temporal growth of wrinkling on a freely propagating planar flame. A second experiment concerns the spatio-temporal growth of structures of controlled wavelength on an anchored flame. The experimental observations are compared to theoretical dispersion relation. Finally, we compare observations of the non-linear evolution to saturation with the predictions of an extended Michelson-Sivashinsky equation.