Bimolecular chemical reactions in shear flow

Abstract The kinetics of bimolecular diffusion-controlled chemical reactions in a presence of shear flow is considered. It is shown that if the second-order rate constant is time-independent in an immobile medium, the influence of flow on the reaction rate is negligible. However, when the rate constant is a decreasing function of time, the flow will result in establishing a time-independent rate constant after a time 1/α (α is the velocity gradient), and the reaction rate at times t ⪢ 1/α can be much higher than in an immobile medium.