CIRCULATION,DIFFUSION, AND REACTION WITHIN A LIQUID TRAPPED IN A CAVITY

The problem of convective diffusion from and reaction within the circulating flow inside a two-dimensional rectangular cavity is studied. The circulation is of the type induced by an external flow. Mass transfer occurs across the interface between the cavity and the external flow. A reactant may diffuse into the cavity from the external flow. The equations of steady motion and transient convective diffusion and chemical reaction are solved numerically. An enhancement factor is defined which quantifies the effectiveness of internal circulation in promoting diffusion and reaction. The dependence of this enhancement factor on geometry (cavity aspect ratio), Peclet number, and kinetic parameters is displayed.