Effect of Flame Front Movement on Local Flow in Turbulent Premixed Flames.

Abstract

An attempt has been made to examine the flame-flow interaction in turbulent premixed flames in a reaction-sheet regime. Vectors of the flame-front movement and gas velocity have been measured simultaneously by use of a two-color, four-beam LDV system and a three-element electrostatic probe at two positions in a turbulent flame brush, i. e., on the centerline and off axis. Change of gas velocity across the flame front differs whether the flame front passes in the unburnt-to-burnt or burnt-to-unburnt direction. When the flame front passes in the burnt-to-unburnt direction, the normal component of the gas velocity to the flame front decreases across the flame front, while the parallel component does not change across the flame front. On the other hand, when the flame front passes in the unburnt-to-burnt direction, the normal component of gas velocity decreases across the flame front. The parallel component increases in the opposite direction to that of the flame front movement.