Some results on simple dynamo systems

A homopolar dynamo for producing current impulses is described. Following the idea of Rioux (1964) and using Moffatt´s model (1979), the equations satisfied by the currents and the velocity are studied. The changes in variables and time scales corresponding to passing from one model to the other, and to the Lorentz´s model if possible, are given. The trajectories of dynamo systems are analyzed in different phase spaces. The aim of this is to study the reliability of the topological analysis of a signal delivered by different equivalent systems, imbedded into different phase spaces. It is noted that the topological properties of an experimental signal in a pseudophase space obtained by delaying the response can give information on the number of variables necessary to describe a complicated phenomenon