Abstract
Abstract–When a catalytic wall reactor is operating properly the boundary walls are at a high temperature and a strong temperature dependent exothermic reaction at the walls heats and reacts the premixed inlet gas mixture. However if the inlet gas temperature falls below a certain critical value T1 the blow out temperature, steady state combustion cannot take place. An order of magnitude analysis is presented which predicts the general form of the blow-out criterion. The equations governing heat and mass transfer in the viscous boundary layers in the inlet region are solved by a combination of asymptotic and numerical methods and an equation for T1 is derived. The effect of radiation is also considered.