Numerical modeling of methane-steam reforming is per formed in a microchannel with heat input through Palladium deposited channel walls corresponding to the experimental setup of Eilers [1]. The low-Mach number, variable density Navier-Stokes equations together with multicomponent reactions are solved using a parallel numerical framework. Methane-steam reforming is modeled by three reduced-order reactions occur ring on the reactor walls. The surface reactions in the presence of Palladium catalyst are modeled as Neumann boundary con ditions to the governing equations. Use of microchannels with deposited layer of Palladium catalyst gives rise to a non-uniform distribution of active reaction sites. The surface reaction rates, based on Arrhenius type model and obtained from literature on packed-bed reactors, are modified by a correction factor to ac count for these effects. The reaction-rate correction factor is ob tained by making use of the experimental data for specific flow conditions. The modified reaction rates are then used to pre dict hydrogen production in a microchannel configuration at dif ferent flow rates and results are validated to show good agree ment. It is found that the endothermic reactions occurring on the catalyst surface dominate the exothermic water-gas-shift re action. It is also observed that the methane-to-steam conversion occurs rapidly in the first half of the mircochannel. A simple one-dimensional model solving steady state species mass frac tion, energy, and overall conservation of mass equations is de veloped and verified against the full DNS study to show good agreement.
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