An a priori model for premixed turbulent flame combustion in the thin reaction zone (TRZ) regime is presented. This deduced from analysis of data series direct numerical simulations (DNS) stoichiometric (ϕ=1.0) iso-octane flames, with Karlovitz number ranging 2.9 to 46.2. For each case two flames are considered: one unity Lewis numbers isolate effect turbulence on flame, and non-unity study inf...

(Received 00 Month 200x; In final form 00 Month 200x) We study the dynamics of thermonuclear flames propagating in fuel stirred by stochastic forcing. The fuel consists of carbon and oxygen in a state which is encountered in white dwarfs close to the Chandrasekhar limit. The level set method is applied to represent the flame fronts numerically. The computational domain for the numerical simulat...

The lagrangian point of view is adopted to study turbulent premixed combustion. The evolution of the volume fraction of combustion products is established by the Reynolds transport theorem. It emerges that the burned-mass fraction is led by the turbulent particle motion, by the flame front velocity, and by the mean curvature of the flame front. A physical requirement connecting particle turbule...

A situation in which a diffusion flame reaches an end at some position in a medium of non-premixed reactants is studied. The mixing of reactants that takes place ahead of the diffusion flame leads to the formation of a "triple-flame", a structure which consists of a fuel-rich premixed flame, a fuel-lean premixed flame. and a diffusion flame that starts where the two premixed flames meet. An imp...

The structure and propagation properties of triple flames subject to buoyancy effects are studied numerically using a high accuracy scheme. A wide range of gravity conditions, heat release, and mixing widths for a scalar mixing layer are computed for ’upright’ and ’inverted’ triple flames (i.e, gravity pointed in parallel and in opposite directions of flame propagation). These results are used ...

The interaction of laminar vortices with a methanol spray counterflow diffusion flame was studied experimentally with vortices generated from either the fuel side or the oxidizer side. The overall stoichiometry was such that the flame resided on the fuel side of the gas-stagnation plane. Local extinction and subsequent reignition were investigated as the circulation of the vortex was varied. It...

The effects of turbulent integral length scale to flame thickness ratio on the bending effect burning velocity variation have been analysed based a three-dimensional Direct Numerical Simulation database statistically planar premixed flames with characteristic Lewis number unity propagating into forced unburned gas turbulence. It has demonstrated that Damköhler's first hypothesis remains valid f...

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We describe flame propagation in a channel subject to a Poiseuille flow, within the thermo-diffusive approximation and an adiabatic context. The two-dimensional flame fronts addressed may be either assisted or opposed by the flow. The problem is characterized by two parameters, the intensity of the flow u0 and the spatial scale e. The total burning rate and the propagation speed are determined ...

In this paper the multi-phenomena deflagration model is used to simulate deflagrative combustion of several fuel–air mixtures in various scale closed vessels. The experimental transient pressure methane–air, ethane–air, and propane–air deflagrations vessels volume 0.02 m3, 1 6 m3 were simulated. includes key mechanisms affecting propagation premixed flame front: dependence laminar burning veloc...