A lattice Boltzmann model for multispecies flows with catalytic reactions is developed, which is valid from very low to very high surface Damköhler numbers (Da s ). The previously proposed model for catalytic reactions [S. Arcidiacono, J. Mantzaras, and I. V. Karlin, Phys. Rev. E 78, 046711 ( 2008)], which is applicable for lowto-moderate Da s and encompasses part of the mixed kinetics and transport-controlled regime, is revisited and extended for the simulation of arbitrary kinetics-to-transport rate ratios, including strongly transport-controlled conditions (Da s → ∞). The catalytic boundary condition is modified by bringing nonlocal information on the wall reactive nodes, allowing accurate evaluation of chemical rates even when the concentration of the deficient reactant at the wall becomes vanishingly small. The developed model is validated against a finite volume Navier-Stokes CFD (Computational Fluid Dynamics) solver for the total oxidation of methane in an isothermal channelflow configuration. CFD simulations and lattice Boltzmann simulations with the old and new catalytic reaction models are compared against each other. The new model demonstrates a second order accuracy in space and time and provides accurate results at very high Da s (∼10 9 ) where the old model fails. Moreover, to achieve the same accuracy at moderate-to-high Da s of O( 1), the new model requires ∼2 d × N coarser grid than the original model, where d is the spatial dimension and N the number of species.

A lattice Boltzmann (LB) interfacial gas-solid 3D model is developed for isothermal multicomponent flows with strongly non-equimolar catalytic reactions, further accounting for the presence of velocity slips and concentration jumps. The model includes diffusion coefficients of all reactive species in the calculation of the catalytic reaction rates as well as an updated velocity at the reactive boundary node. Lattice Boltzmann simulations are performed in a catalytic channel-flow geometry under a wide range of Knudsen (Kn) and surface Damköhler (Das) numbers. Comparisons with simulations from a computational fluid dynamics (CFD) Navier-Stokes solver show good agreement in the continuum regime (Kn < 0.01) in terms of flow velocity and reactive species distributions, while comparisons with literature Direct Simulation Monte Carlo (DSMC) results attest the model's applicability in capturing the correct slip velocity at Kn as high as 0.1, even with significantly reduced number of grid points (N = 10) in the cross-flow direction. Theoretical and numerical results demonstrate that the term Das × Kn × A2 (where A2 is a function of the mass accommodation coefficient) determines the significance of the concentration jump on the catalytic reaction rate. The developed model is applicable for many catalytic microflow systems with complex geometries (such as reactors with porous networks) and large velocity/concentration slips (such as catalytic microthrusters for space applications).

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