Effect of molecular transport on PDF modeling of turbulent non-premixed flames

Improvements of the combustion characteristics by the hydrogen enrichment

“…The model constants used for all the computations in this paper have been set up for academic configurations such as turbulent combustion and homogenous isotropic turbulence [5][6][7][8] ( t x P Ψ as a density-weighted joint PDF of φ , the Favre filtering or Favre averaged of a statistical quantity or the joint Favre probability density function of the subgrid scalar fluctuations that can be evaluated using [10,11],…”

“…Therefore, the mixture fraction is considered as the scalar variable, the equation (11) becomes [5,[9][10][11]:…”

“…For non-premixed combustion, additional scalar variable of mixture fraction Z ( x ,t) is needed. The transport equation of mixture fraction is such as [9][10][11],…”

“…The above two equations can be combined to be applied in whichever premixed, partially premixed, or nonpremixed flames [9][10][11][12]. In the case of simple global reaction rate, progress variable c ( x ,t) is often used instead of f Ỹ ( x ,t) for convenience.…”

“…But for the premixed combustion with coflow of air or pilot product, following equation can be applied to express the lean reactant mass fraction [9][10][11]12],…”