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Detailed spray measurements for the Engine Combustion Network "Spray G'" have been collected while operating at flashing conditions. Time-resolved fuel density was measured through tomographic x-ray radiography for neat iso-octane and a blend of 80% iso-octane with either 20% butanol or 20% ethanol by volume under a flash-boiling condition. Lastly, these same fuels were used during the collection of ultra small angle X-ray scattering (USAXS) measurements to quantify the specific surface area of the spray in the near-nozzle region. Spray density profiles generated through tomographic reconstruction of the radiography measurements reveal the high dispersion of the fuel under the flashing condition. This injection behavior also causes the individual plumes to collapse and interact with each other, which can lead to additional flow field perturbations. These maps also show density discrepancies between the fuel blends caused by their differing vaporization profiles. The spray differences between these fuels are further highlighted through the specific surface area profiles of droplets in the plumes. This combination of radiography and USAXS measurements provide a valuable quantification of the resulting spray morphology.
