Macroscopic Liquid Metal Experiments at Illinois David N. Ruzic Department of Nuclear, Plasma, and Radiological Engineering University of Illinois at Urbana Champaign

Tokamak First Wall : self propelled metal concept externally supplied current may cause metal to flow up outboard wall

General Schematic of Experiment  14 Amp current

Hydrogen plasma discharge interaction with liquid gallium l A current through the liquid gallium metal was not shorted when a hydrogen plasma was present even with a large current flow though liquid metal.

Magnetic Field Gradient

J X B Force downward Force Metal in gradient area rises But current density also increased ! current lead

First Liquid Gallium Experiments l Metal in gradient area is not pushed down as hard as metal in stronger field. l Level rises about 3 mm. l Metal does not flow up the curved wall. l But current density increases near the wire so J goes up as B goes down.

Second Liquid Gallium Experiments l Replace wire current lead with a paddle shaped electrode to keep current density constant as gallium rises up the curved wall l Don’t make electrode out of aluminum! l Results showed a 2 mm displacement along curved surface at full field and 9 Amps