The effect of vortex stirring on reaction rate enhancement is investigated for two reactive
scalars initially separated by a third nonreactive scalar. The presence of the intervening
scalar precludes reactions at early times. Vortex stirring accelerates the coalescence of the
reactive scalars relative to pure diffusion and enhances the resulting reaction rates.
Analytical and numerical results for reactive stirring by a single point vortex are shown for a
range of Péclet (Pe) and Damköhler (Da) numbers. At low Da and high Pe, nondimensional …