Reduced and normal gravity combustion experiments were performed with fiber-supported methanol droplets with initial\r\ndiameters in the 1mm size range. Experiments were performed with air-diluent mixtures at about 0.101MPa and 298 K, where\r\ncarbon dioxide, helium, or xenon was separately used as the diluent gas. Results indicate that ambient gas transport properties\r\nplay an important role in determining flammability and combustion behaviors including burning rates and radiant heat output\r\nhistories of the droplets. Droplets would burn with significantly higher mole fractions of xenon than helium or carbon dioxide.\r\nIn reduced gravity, droplets would burn steadily with a xenon mole fraction of 0.50 but would not burn steadily if helium or\r\ncarbon dioxide mole fractions were 0.50. Comparison with previous experimental data shows that ignitability and combustion\r\ncharacteristics of droplets are influenced by the fuel type and also the gravitational level. Burning rates were about 40% to 70%\r\nhigher in normal gravity than in reduced gravity. Methanol droplets also had burning rates that were typically larger than 1-\r\npropanol burning rates by about 20% in reduced gravity. In normal gravity, however, burning rate differences between the two\r\nfuels were significantly smaller.
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