A MODEL OF ELEMENTARY CHEMISTRY AND FLUID-MECHANICS IN THE COMBUSTIONOF HYDROGEN ON PLATINUM SURFACES

Using computational methods, we consider the catalyzed combustion of l ean hydrogen-oxygen mixtures in a stagnation flow over a platinum surf ace and in a flat-plate boundary layer. The analysis includes elementa ry chemistry in the gas phase as well as on the surface. The stagnatio n flow is modeled using a similarity transformation that leads to a on e-dimensional boundary-value problem, whereas the flat-plate boundary layer is modeled by the use of the boundary-layer assumption. Predicti ons of each model are compared with experimental measurements of (a) c atalytic ignition and combustion of hydrogen-oxygen mixtures at low pr essure (100 millitorr) and (b) OH concentration profiles in catalytica lly supported combustion at atmospheric pressure. The article proposes reaction mechanisms and interprets the catalytic behavior in terms of the chemistry models.