HYDRODYNAMIC TURBULENCE AND DIFFUSION-CONTROLLED REACTIONS - SIMULATION OF THE EFFECT OF STIRRING ON THE OSCILLATING BELOUSOV-ZHABOTINSKY REACTION WITH THE RADICALATOR MODEL

Different stirring effects of the Belousov-Zhabotinsky (BZ) reaction observed by previous authors and also reported here can be explained and modeled semiquantitatively by a diffusion-controlled radical-radical reaction step of the Radicalator. It is shown that hydrodynamic turbulence can accelerate the rate of a diffusion-controlled reaction considerably provided that both reactants of the diffusion-controlled step are present in low concentrations (less than 10(-6) M). A stirring effect can indicate the presence of a diffusion-controlled step in the mechanism of other (non-BZ) reactions as well. Finally, it is found that uniform ultrasonic stirring can substitute for the less uniform mechanical stirring in the BZ reaction.