CHEMICAL-REACTIONS IN CHAOTIC FLOWS

Chemical reactions in time-periodic 2D chaotic flows; reexamined by so lving numerically the convection-diffusion-re action equation. Three f low conditions are considered: a predominantly regular system, a predo minantly chaotic system with a few regular islands, and a globally cha otic system devoid of noticeable islands. Chaotic mixing has a strong impact on systems undergoing a single bimolecular reaction A + B --> C . Maximum concentration of C occurs in well-mixed chaotic regions; in comparison, little reaction takes place inside poorly mixed non-chaoti c islands. Chaotic mixing also has a significant impact on competitive -consecutive reactions A + B --> P, B + P --> W. The relative amounts of P and W generated by the reactions are strongly affected by the pre sence of islands. While the desired product P predominates in chaotic regions, most of the waste W is generated inside islands.