Far-Field Breakup

Reaction-diffusion equations with M. Bär and M. Eiswirth kinetics [8] are simulated. The initial condition is a stable rotating spiral for $\epsilon=0.072$. At the beginning of the simulation $\epsilon$ is changed to $0.075$. The spiral wave trains begin to modulate and eventually the spiral breaks in the far-field region. Linear stability computations as these parameter values show that the spiral is linearly unstable.

Model Parameters for simulation:

$$\begin{eqnarray*}a=0.84, b=-0.045, \epsilon=0.075, D_v=0, L_x=L_y=160.\end{eqnarray*}$$

Note: For these parameters the spiral breakup is very sensitive to details of the simulation. Small changes in numerical parameter may result in breakup closer or further from the spiral center.