ABSTRACT

Introduction Magnetically confi ned fusion plasmas are thermodynamically nonequilibrium systems, where particles and energy are injected (or generated by fusion reaction) deep in the plasma, providing heat which fl ows towards the much colder edge region . This creates a kind of heat engine that drives both turbulent fl ows and more laminar zonal fl ows, somewhat analogous to the way solar energy deposition near the equator drives the dynamics of planetary atmospheres and oceans (see Fig. 1).