This paper describes an experimental exploration of droplet#x2013;droplet and droplet#x2013;flame interactions in a self-sustained rectilinear monodispersed droplet stream flame. Fuel droplets in the stream have an initial diameter of approximately 1OO#xB5;m and travel at an average velocity of 1Om/s (Reynolds number approximately 100) vertically upward. The initial center to center droplet spacing is between 2 and 10 droplet diameters. The droplet stream ignites as it passes through an electrically heated coil of bare nickel#x2013;chromium wire. Vaporization rates are computed from changes in droplet size that are measured from photographs. The results indicate that, as the spacings examined, droplet vaporization rates in the stream flame differ from isolated droplet vaporization rates. In this spacing regime, the decrease in the vaporization rate is almost linear with decreasing droplet spacing. At a constant mass flow rate in the droplet stream, the total mass vaporization increases as the initial droplet size and spacing decreases, even though the individual droplet vaporization rates decreases. The increased total surface area with decreased droplet size counteracts the droplet interaction effects. The trends of the vaporization results are independent offuel type, but the structure of the stream flame, and particularly the behavior of the sooting region, is very sensitive to the fuel used. A thin blue non#x2013;sooting flame escapes the top of the soot plume when pure hydrocarbon fuels burn. indicating that shoot formation ends before the liquid fuel completely burns out.
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