Fuel droplet vaporization under asymmetric thermofluid conditions is prevalent in many combustion related devices. Asymmetric thermal radiant heating in particular, is important in spray flames, counter-flow dif- fusion flames, regions close to the walls of conventional combustors and more importantly in liquid-fueled microcombustors. Even though extensive studies on droplet vaporization involving thermal radiation have been performed, the area of asymmetric thermal radiation absorption has not yet been explored. In this talk, I present the results of an experimental study, which uses the planar laser-induced fluorescence (PLIF) diagnostic tool to investigate the vaporization phenomena of fuel droplets exposed to asymmetric thermal irradiation. Results, in the form of PLIF images, reveal highly asymmetric vapor distribution around the droplets with the apparent induction of Stefan flow from the droplet surface, for the case of asymmetric radiant heating. Such phenomena have not previously been reported in the literature and have relevance to the overall fuel vaporization process. To further validate the experimental findings, an analytical model revealing the volumetric radiation absorption distribution inside the liquid droplets, is explained.
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pdf file (Ammigan - Fermilab technical seminar.pdf, 2.2 MB)