Spiral wave
Spiral waves , also known as vortex waves or spiral waves in English-language literature , are a special form of two-dimensional chemical waves . Three-dimensional spiral waves are also known as scrollwaves . The possibility of the creation of spiral waves was first theoretically predicted in 1946 by Norbert Wiener and Arturo Rosenblueth . Spiral waves can be observed, for example, when the heart muscle is stimulated .
Spiral waves are a manifestation of autocatalytic waves. These can also appear as self-contained circular wavefronts or they have two ends that touch the boundaries of the propagation medium . Spiral waves, on the other hand, are characterized by the fact that one end of the wave front always runs along the boundary of the medium, while the other, the core, moves freely in the medium.
This movement can take place on different trajectories (i.e. trajectories), which are determined by the type of medium and the specific diffusion and reaction parameters:
- self-contained trajectories
- open trajectories.
The self-contained trajectories have circular and elliptical orbits. Depending on the constellation of the parameters, the cores can also drift, which often results in self-contained rosettes . But there can also be quasi-periodic movements that create open rosettes.
If the core of the spiral wave collides with a medium boundary, a closed wave front is created again, as both ends of the wave now touch the medium boundary; the existence of the spiral wave is thus ended.
In principle, spiral waves are created by breaking up a closed wave front. This can be done in different ways.
Individual evidence
- ↑ Polina S. Landa: Nonlinear Oscillations and Waves in Dynamical Systems . Springer, 1996, ISBN 0-7923-3931-2 , pp. 440 ( limited preview in Google Book Search).
- ↑ Pertsov, Arkady M., et al. "Spiral waves of excitation underlie reentrant activity in isolated cardiac muscle." Circulation Research 72.3 (1993): 631-650. [1]
- ↑ Paolo Arena (Ed.): Nonlinear Noninteger Order Circuits and Systems: An Introduction . World Scientific, 2000, ISBN 981-02-4401-0 , pp. 120 ff . ( limited preview in Google Book search).
- ↑ Vladimir Sergeevich Zykov: Simulation of Wave Processes in Excitable Media . Manchester University Press, 1987, ISBN 0-7190-2472-2 , pp. 10 ( limited preview in Google Book search).