CHEMICAL-INSTABILITY INDUCED BY A DIFFERENTIAL FLOW

A new kind of instability is predicted for a system involving activator and inhibitor kinetics in a reactive flow. It is shown that a differential flow of activator and inhibitor, achievable, e.g., by selectively binding one component to a support, can destabilize the spatially homogeneous state of the system in a similar way as differential diffusivity does in the case of the Turing instability. The differential-flow-induced chemical instability is of the traveling-wave type. It is free from the restrictions of the Turing instability on the diffusion coefficients and can thus be expected to occur in a wide variety of natural and artificial systems.