Homogeneous Combustion in Micro Channels

1 Modeling of Homogeneous Methane Combustion in Micro Channels 

Raimondeau et al. [74] modeled the homogeneous high-temperature combustion of a preheated stoichiometric mixture of methane and air at a flow rate of 2 m s 1 and a reference temperature of1 000 °C, which corresponds to the methane ignition temperature under these conditions. Fora channel of 100 pm diameter, no gradients of species concentration and temperature were determined by the calculations. It was demonstrated that temperature losses through the wall lead to flame extinction, which was more pronounced with decreasing channel diameter. 

In addition, flame propagation is not possible in stainless-steel channels owing to the high heat conductivity and affinity to radicals. But even for materials which do not adsorb radicals, a minimum channel width exists below which no homogeneous combustion is possible any longer. Insulating materials such as silicon nitride and inert layers such as alumina are required to maintain the homogeneous reaction. 

A minimum flow velocity was required to maintain a flame. When the flow velocity of the feed was increased, the location of the flame first moved upstream and then downstream again, while the width of the reaction zone decreased and the maximum 

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Homogeneous combustion in micro-channels Hydrocarbon reforming Averaged signal height... 

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