Non-Steady Behaviour of a Spiral under a Constant Current

Abstract

We present an experimental study of the motion of a rotating spiral in the Belousov-Zhabotinsky reaction in an "almost open" reactor, under the influence of a constant external current. We provide a simple model based on symmetries to explain the previous experimental observations, but show that it is unable to describe the true motion of a spiral. The motion of a spiral cannot be reduced to that of its centre: global deformation modes must also be taken into account.