Numerical investigation of catalytic combustion in a honeycomb monolith with lean methane and air premixtures over the platinum catalyst

Abstract

The stringent regulation requires low hydrocarbon emissions in combustion engines with high priority to environmental protection. For low emission technologies, catalytic combustor is an attracting option for the stable combustion process, which operates at lower temperatures than conventional engines. In this work, numerical analysis of the catalytic combustion with lean premixed methane and air is performed employing a cylindrically shaped honeycomb monolith combustor coated with the platinum catalyst. Detailed diagnostic investigations of complete catalytic combustor have been carried out using honeycomb monolith reactor in order to examine the comprehensive gaseous and catalytic surface reactions. The surface chemistry introduced by Chou on the monolith reactor consisting of numerous channels engaged along the cross-section is employed to examine the monolith temperatures and methane conversions during surface ignition. The species and surface site fractions are predicted with adsorbed species as the function of the monolith. The parameters such as the inlet temperature, fuel/air ratio, and velocity serve to govern the behavior of the catalytic combustion monolith. The reasonable requirement of catalytic combustor length for the complete combustion of the lean methane-air mixture is also determined by the numerical simulation over the platinum-coated honeycomb monolith.