Simulations of reacting droplets dispersed in isotropic turbulence

Several important issues pertaining to dispersion and polydispersity of eva porating and reacting fuel droplets in forced turbulent hows are investigat ed. The carrier phase is considered in the Eulerian context and is simulate d by direct numerical simulation. The dispersed phase is tracked in the Lag rangian frame and the interactions between the phases are taken into accoun t in a realistic two-way coupled formulation. It is assumed that combustion takes place in the vapor phase and is described as fuel + oxidizer --> pro ducts + energy. The resulting scheme is applied far extensive simulations o f a forced, isotropic, low Mach number turbulent flow laden with a large nu mber of fuel droplets. Here the results are presented for different values of the mass loading ratio and the heat release coefficient. The combustion process is significantly affected by the Fate of evaporation and the fuel v apor participates in the chemical reaction almost immediately after its pro duction. A strong correlation is observed between the droplet concentration and the reaction rate. The results are also used to discuss the temporal e volution of the mean temperatures and the mean mass fractions, as well as t he role of the preferential distribution of the droplets.