Regensburg 2007 – wissenschaftliches Programm
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DY: Fachverband Dynamik und Statistische Physik
DY 24: Poster I
DY 24.27: Poster
Mittwoch, 28. März 2007, 16:00–18:00, Poster D
Reorientation of a scroll ring under an electrical current in a chemical excitable medium — •Chaiya Luengviriya1,2, Stefan C. Müller1, and Marcus J. B. Hauser1 — 1Otto-von-Guericke-Universtität Magdeburg, Institut für Experimentelle Physik, Abteilung Biophysik, Universitätsplatz 2, 39106 Magdeburg, Germany — 2Kasetsart University, Department of Physics, Bangkok, 10900, Thailand
Scroll rings are three-dimensional wave structures in excitable media whose filaments form closed loops. Such filaments are subject to wave instabilities which cause the scroll rings to expand or contract intrinsically depending on the excitability of the medium. Even though the length of filament changes due to expansion or contraction, the position and orientation of the scroll ring are approximately stationary - the filament does almost neither drift nor rotate.
We present a study of the dynamics of a scroll ring in a Belosov-Zhabotinsky (BZ) reaction under a constant electrical current. The scroll ring reoriented itself with respect to the direction of the applied electric current. In addition, a linear drift against the direction of the current was observed. These effects were coupled with an intrinsic contraction leading to a self-annihilation of the scroll ring. Numerical calculations show that electrical current and temperature gradients have similar effects on the dynamics of a scroll ring in a BZ reaction. However, temperature gradients cannot cause drifts of scroll rings as in the case of electrical current.