Laminar Smoke Points of Nonbuoyant Jet Diffusion Flames
نویسندگان
چکیده
The laminar smoke point properties of jet diffusion f lames-the luminous flame length, the residence time, and the fuel flow rate, at the onset of soot emission from the flames--have proven to be useful global measures of the soot properties of nonpremixed flames. These measures provide a means to rate several aspects of sooting properties: the relative tendency of various fuels to emit soot from flames [1-4]; the relative effects of fuel structure, flame temperature, and pressure on the soot properties of flames [5-10]; and the relative levels of continuum radiation from soot in flames [11-13]. Measurements of laminar smoke point properties generally are based on round buoyant jet diffusion flames, surrounded by a coflowing air (or oxidant) stream to prevent the flame pulsations characteristic of buoyant diffusion flames in still environments. Laminar smoke point properties found from this configuration are relatively independent of burner diameter and coflow velocities, which has helped to promote their acceptance as global measures of soot properties [9]. However, recent studies suggest potential for fundamental differences between the laminar smoke point properties of buoyant and nonbuoyant flames [9,14]. Thus, the overall objective of the present investigation was to measure the laminar smoke point properties of
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