Dynamical stability of untwisted scroll rings in excitable media (Q1118509)

We report numerical simulations of the dynamical behavior of three- dimensional untwisted scroll rings, for three different models of excitable media. The computations reveal, for the first time, the existence of a stable, steadily rotating (non-drifting as well as non- expanding/shrinking) scroll wave near a wall. Expansion of the scroll ring is observed for different choices of kinetic models, along with contraction and drift. Numerical calculations also indicate aperiodic or meandering movement of the three-dimensional scroll ring near the wall. Contrary to earlier observations some scroll rings do not drift noticeably at any value of the diffusion coefficient of the recovery variable.