An experimental study was conducted to investigate unsteady effects of velocity disturbance on the premixed flame in a tube. The velocity disturbance was induced by piston movement. The magnitude and the residence time of velocity disturbance were controlled by velocity and stroke of the piston.
The steady flame which was located in a tube undergoes unsteady behavior by the velocity disturbance. The changes of flame propagation velocity, flame shape, and flame intensity were studied for various equivalence ratios and different velocity disturbances.
We studied the extinction condition of the flame with different magnitude and residence time of disturbance and we also found the condition for the appearance of the tulip-flame.
The variation of the flame intensity in the small time scale, which is smaller than the reaction time scale, the influence of tangential and volumetric stretch effect on the flame.
