Modeling and Simulation of Hydrogen-Oxygen Combustion on Platinum Catalyst

Abstract

Using computational methods, the catalyzed combustion of lean hydrogen-oxygen mixtures in a stagnation flow over a platinum surface and in a flat-plate boundary layer is considered. The analysis includes elementary chemistry in the gas phase as well as on the surface. The stagnation flow is modeled using a similarity transformation that leads to a one-dimensional boundary-value problem, whereas the flat-plate boundary layer is modeled by use of the boundary layer assumption. Results of the models are compared to two sets of experiments that determine (a) catalytic combustion and ignition limits in hydrogen-oxygen mixtures at low pressure (100 mTorr) and (b) OH concentration profiles in catalytically supported combustion at atmospheric pressure. The paper establishes the appropriate reaction mechanisms and interpretes the catalytic behavior in terms of the chemistry models.