Modeling of Heat Transfer in a Porous Monolith Catalyst with Square Channels

Abstract

Interaction of gas flow heterogeneity and heat flow distribution in porous honeycomb catalyst with square channels is under study by 3D Navier–Stokes equations for methane oxidation as model reaction. Gas stream passes through the monolith frontal surface into porous structure which generates complex rearrangement of the gas flow entering the monolith channel, and therefore sharp gradients of the heat flow form between the channel wall and gas stream. The catalyst temperature differs significantly from that of the gaseous medium, increases abruptly, and causes fast reduction of methane concentration in the near-wall region. The gas temperature grows noticeably at certain distance from the inlet, and its distribution along the channel is rather smooth. Axial profiles of Nusselt number determined by local heat transfer characteristics are close in different cases: for constant wall temperature and nonuniform distribution of the thermal characteristics as well as in the cases without and with catalytic reaction.