Review of FTU results with the liquid lithium limiter

Since the end of 2005 a liquid lithium limiter has been installed on FTU. The liquid lithium is confined by capillarity in a mat of stainless steel or other refractory material and the capillary force counteracts the electromagnetic force. In this paper we review some of the most important results obtained in the experimental campaigns led on FTU. Peaked electron density profiles are spontaneously formed when the density exceeds 1.0 × 1020 m−3. Despite to the fact that FTU is a fully metallic machine with a TZM toroidal limiter, the only impurity that is present in the plasma is lithium so that very clean plasma are obtained and the beneficial effects are discussed. Heat loads in excess of 5 MW/m2 are withstood by the limiter without any damage also because the radiative losses from the evaporated lithium are able to dissipate most of the incoming heat flux.