An Extinction Criterion for a Catalytic Wall Reactor

Abstract

When a catalytic wall reactor is operating properly the boundary walls of the reactor are at a high temperature and a strong temperature dependent exothermic reaction at the walls heats and reacts the inlet gas. However if the inlet gas temperature is reduced below a certain value T ^*_I , the blow-out temperature, steady state combustion cannot take place. Combustion ceases first in the inlet region, but eventually combustion ceases in the whole reactor. In this paper we formulate the equations which govern steady heat and mass transfer in the boundary layer in the inlet region of the reactor. At high activation energies an order of magnitude analysis can be performed to yield an equation for the blow-out temperature T ^*_I involving a single order one constant β^* a parameter which can be found by solving the governing equations. The solution for T ^*_I is however insensitive to the value of β^*.