by
Karl-Heinz Rädler(Astrophysical Institute Potsdam)
→
Europe/Stockholm
FA31
FA31
Description
It is generally accepted that most of the magnetic fields of cosmic
objects are generated and maintained by dynamo action, that is, by
induction effects in moving electrically conducting fluids. In the last
decades the theory of cosmic dynamos has been widely elaborated. The
experimental demonstration of dynamo effects requires notable technical
efforts. A large volume of fluid showing high electrical conductivity
and high flow velocities is needed. At the end of 1999 two such
experiments, both with liquid sodium but very different flow patterns,
ran first time successfully, one in Riga (Latvia) and one in Karlsruhe
(Germany). In the mean time a third one succeeded in Cadarache (France). Some
more experiments are under preparation. In the talk some elements of
dynamo theory will be explained and these experiments will be described
and discussed.
