Area Rules for the Diffusion Flame of a Moving Bunsen Burner Corresponding to Different Temperature Ranges
A high-speed camera system is used to observe the diffusion flame of a Bunsen burner in linear motion. The resultant sequence of instantaneous motion pictures of the flame accelerating at 3.60 m/s2 is processed and used to study the change in the flame area and specific floor area of the flame over different temperature ranges. The results indicate that the total flame area increases in the fuel control zone as the velocity increases over the range of experimental speeds employed (< 0.90 m/s); then the total area quickly decreases in the transition region and is stable in the cross-flow wind control zone. As the velocity of the fire source increases, the low-temperature and specific floor areas adopt more dominant positions in the low-speed fuel control zone. In the high-speed cross-flow wind control zone, the area of the high-temperature zone and specific floor area take the dominant positions. The transformation between the two situations occurs in the transition zone. The cross-flow wind increases the high-temperature specific floor area of the fire compared to that of a stationary fire; the consumption in the moving fire also becomes correspondingly more concentrated and fierce.