The filtered mass density function (FMDF) model (Jaberi et al. 1999 [1]) is employed for large eddy simulations (LES) of “high speed” partially-premixed methane jet flames with the “flamelet” and “finite-rate” kinetics models. The FMDF is the joint probability density function (PDF) of the scalars and is determined via the solution of a set of stochastic differential equations. The LES/FMDF is implemented using a highly scalable, parallel hybrid Eulerian–Lagrangian numerical scheme. The LES/FMDF results are shown to compare well with the experimental data for all flow conditions when “appropriate” reaction and mixing models are employed.

10aFiltered mass density function; PDF methods; Monte-Carlo simulations; Methane jet flames10aLES1 aYaldizli, M.1 aMehravaran, K.1 aJaberi, F.A. uhttps://icer.msu.edu/research/publications/large-eddy-simulations-turbulent-methane-jet-flames-filtered-mass-density-001283nas a2200133 4500008004100000245009500041210006900136260005900205520071100264100001700975700001900992700001701011856012101028 2009 eng d00aLarge-Eddy Simulations of Turbulent Methane Jet Flames with Filtered Mass Density Function0 aLargeEddy Simulations of Turbulent Methane Jet Flames with Filte aAnn Arbor, MichiganbThe Combustion Institutec05/20093 aThe filtered mass density function (FMDF) model (Jaberi et al. 1999 [1]) is employed for large eddy simulations (LES) of “high speed” partially-premixed methane jet flames with the “flamelet” and “finite-rate” kinetics models. The FMDF is the joint probability density function (PDF) of the scalars and is determined via the solution of a set of stochastic differential equations. The LES/FMDF is implemented using a highly scalable, parallel hybrid Eulerian–Lagrangian numerical scheme. The LES/FMDF results are shown to compare well with the experimental data for all flow conditions when “appropriate” reaction and mixing models are employed.

1 aYaldizli, M.1 aMehravaran, K.1 aJaberi, F.A. uhttps://icer.msu.edu/research/publications/large-eddy-simulations-turbulent-methane-jet-flames-filtered-mass-density02163nas a2200193 4500008004100000245008900041210006900130260001200199300001200211490000800223520143600231653002801667653008201695100001701777700001701794700001901811700001701830856012201847 2008 eng d00aThe Structure of Partially-Premixed Methane Flames in High Intensity Turbulent Flows0 aStructure of PartiallyPremixed Methane Flames in High Intensity c09/2008 a692-7140 v1543 aDirect numerical simulations (DNS) are conducted to study the structure of partially premixed and non-premixed methane flames in high-intensity two-dimensional isotropic turbulent flows. The results obtained via “flame normal analysis” show local extinction and reignition for both non-premixed and partially premixed flames. Dynamical analysis of the flame with a Lagrangian method indicates that the time integrated strain rate characterizes the finite-rate chemistry effects and the flame extinction better than the strain rate. It is observed that the flame behavior is affected by the “pressure-dilatation” and “viscous-dissipation” in addition to strain rate. Consistent with previous studies, high vorticity values are detected close to the reaction zone, where the vorticity generation by the “baroclinic torque” was found to be significant. The influences of (initial) Reynolds and Damköhler numbers, and various air–fuel premixing levels on flame and turbulence variables are also studied. It is observed that the flame extinction occurs similarly in flames with different fuel–air premixing. Our simulations also indicate that the CO emission increases as the partial premixing of the fuel with air increases. Higher values of the temperature, the OH mass fraction and the CO mass fraction are observed within the flame zone at higher Reynolds numbers.

10aDNS; Methane combustion10aturbulent reacting flows; partially premixed flames; reduced chemistry models1 aYaldizli, M.1 aMohammad, H.1 aMehravaran, K.1 aJaberi, F.A. uhttps://icer.msu.edu/research/publications/structure-partially-premixed-methane-flames-high-intensity-turbulent-flows