The influences of initial mixture distribution on localized forced ignition of globally stoichiometric stratified mixtures have been analyzed using three-dimensional compressible direct numerical simulations. The globally stoichiometric mixtures (i.e., hϕi ¼ 1:0) for different root-meansquare (rms) values of equivalence ratio (i.e., ϕ 0 = 0.2, 0.4, and 0.6) and the Taylor micro-scale lϕ of equivalence ratio ϕ variation (i.e., lϕ=l f ¼ 2.1, 5.5, and 8.3 with l f being the Zel'dovich flame thickness of stoichiometric mixture) have been analyzed for different initial rms values of turbulent velocity u 0 . The equivalence ratio variation is initialized following both Gaussian and bi-modal distributions for a given set of values of ϕ 0 and lϕ=l f in order to analyze the effects of mixture distribution. The localized forced ignition is accounted for by considering a source term in the energy conservation equation that deposits energy for a stipulated time interval. It has been demonstrated that the initial equivalence ratio distribution has significant effects on the extent of burning of stratified mixtures following successful localized forced ignition. It has been found that an increase in u 0 =S b ϕ¼1 ð Þ (ϕ 0 ) has adverse effects on the burned gas mass, whereas the effects of lϕ=l f on the extent of burning are nonmonotonic and dependent on ϕ 0 for initial bi-modal mixture distribution. The initial Gaussian mixture distribution exhibits an increase in burned gas mass with decreasing lϕ=l f , but these cases are more prone to flame extinction for high values of u 0 than the corresponding bi-modal distribution cases. Detailed physical explanations have been provided for the observed mixture distribution, ϕ 0 , u 0 , and lϕ=l f dependences on the extent of burning following localized forced ignition of stratified mixtures.
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