Conditional Moment Closure Modeling of Turbulent Spray Combustion in a Direct Injection Diesel Engine

which are in a nonconservative form. Global conservation is not guaranteed if integration is performed for Eqs. (2) and (3), which do not include PDF inside the temporal and spatial derivatives. On the other hand nonconservative forms allow a relatively coarse mesh since conditional averages show much less spatial dependence than PDF weighted Favre averages. Here η ρ ρ η ≡ and the scalar dissipation rate is N D ξ ξ ≡ ∇ ∇ i where is the molecular diffusion coefficient of mixture fraction. , and are conditional fluctuations about the conditional averages. The last term on right hand side of Eq. (4) reflects the effect of increasing or decreasing cylinder pressure on conditional enthalpy. The conditional mean reaction rate is modeled in the first order closure as D Y ′′ h′′ ′′ u