Modified Propagation of Anomalous Belousov-Zhabotinsky Waves in a Quasi-1D System

Jack Mershon

2018

The Belousov-Zhabotinsky (BZ) reaction was used to investigate the effect of fluid flow on the propagation behavior of reaction-diffusion (RD) waves. Solutions were filled into glass capillaries to create quasi-1D systems. The normal regime was advected at its propagation speed to determine if this would produce a stationary wave. This did not work precisely and other speeds were tested. Two anomalous wave behaviors, named stacking and merging, were investigated as well. Stacking behavior is characterized by an initial wave front being tailed by faster waves that slow to the propagation speed of the first wave, producing a series of stacked waves. Merging is similar to stacking except the secondary waves die off as they approach the initial wave’s inexcitable refractory tail. The anomalous mixtures were also subjected to advection at a speed equivalent to their nominal propagation speed. Other advection speeds were tested by not thoroughly. The advection of the normal regime resulted in the initial fronts propagating at a significantly reduced speed than normal, though some forward propagation was still observed suggesting that the flow was not sufficient to stop forward wave propagation. Higher speeds were attempted and it was shown that waves could be stopped but at a speed not its nominal propagation speed. Normal propagation was found to have the distance between wave fronts greatly increased by advection. The development of precise anomalous modes was not observed but compelling results for chemical gradience in anomalous regimes were seen during experimentation. That is, it would seem advection is causing different chemical concentrations to develop in different regions of the capillary.