Structure of Premixed Turbulent Flames : Part 1 Flames Dominated by Coherent Structures

Abstract

Flames dominated by coherent structures often appear in the shear layer between a couple of parallel streams of hot burnt gas and a cold unburnt mixture. Such flames were investigated by the synchronized Schlieren photography and electrostatic probing technique as well as by the laser Doppler anemometry. The ion current measurements conditioned by the instantaneous Schlieren photography showed that the most violent reaction occurred at the part of a coherent vortex where the unburnt mixture was engulfed. The flame is coupled with microstructures in coherent vortices and has the structure of a 'wrinkled laminar' flame.