A finite-difference reaction-diffusion PDE (Barkley excitable-medium model) integrated on a 2D
concentration grid — the canonical top-down view of BZ spiral and target waves, colour-mapped by
activator concentration.
Click / tap the canvas to seed a new spiral wave
0.0
Sim time (a.u.)
0
Active waves (est.)
0
Seeds planted
Diffusion rate (Du)1.00
Reaction rate (1/ε)20
Grid resolution
Reaction-diffusion model. Two coupled fields evolve on a toroidal grid: an
activator u (HBrO₂-like, fast) and an inhibitor v (oxidised catalyst, slow),
integrated with explicit finite differences —
∂u/∂t = k·u(1−u)(u−(v+b)/a) + Du·∇²u,
∂v/∂t = u − v + Dv·∇²v. This is the same class of activator-inhibitor kinetics
behind the Oregonator model discussed for the 3D version: raising the reaction rate speeds up
front propagation, raising diffusion widens and smooths the spiral arms.