Probability density functions for fluctuations in turbulent two-phase flames

Probability density function methods for characterizing various fluctuating quantities in the reacting gas phase of turbulent spray flames are presented, development which O'Brien has been a pioneer. Balance equations two-phase flows considered as piecewise continuous medium first presented with interface conditions containing vaporization–condensation equilibrium. From these, equation joint probability temperature and composition is derived, specific terms related to vaporization identified. The that require modeling then highlighted. one classical micromixing term, include all features already discussed single flows, but adaptation be questioned. Mainly, several unclosed deal vaporization, requiring attention. It shown proposals their can obtained on same basis so-called Eulerian–Lagrangian models, will directly induce changes shape function. We finally discuss model herein comment its connection recently published literature this subject. Specific attention devoted combustion regimes presence diffusion flamelets surrounding fuel droplets or groups droplets. here go step further compared recent studies, now, they have well-defined experiments, numerical experiments direct simulations, real conveniently controlled conditions.