Turbulent Mixing in the Presence of Liquid Droplets with Application to Spray Combustion Venkatramanan Raman Department of Aerospace Engineering and Engineering Mechanics University of Texas at Austin Computational modeling of spray combustion faces many unique challenges. The flame structure in spray systems is governed by the local mixing rates, the spatial distribution and evaporation rates of these droplets. For this reason, single phase combustion models that presume the flame structure based on the operating conditions cannot be applied to these multiphase flows. Here, we have developed a probability density function (PDF) based combustion modeling approach that can describe such complex flame structures. Using direct numerical simulation, we have established that the proposed methodology accurately captures the flame structure. A novel computational algorithm based on Monte-Carlo approach has been developed. This algorithm is found to be numerically stable and accurate for a range of operating conditions. Temperature Fuel Mass Fraction