Russian Demo Plant Study

A conceptual design study of Demo reactor is being continued in Russia. The main efforts are concentrated on the study of steady state reactor Demo-S. This reactor is to be operated in advanced plasma regime with high fractio n of bootstrap current. A divertor concept with open liquid lithium as a pl asma facing material was chosen. Two extreme approaches were analized: the first one assumes that liquid Lithium is loaded with direct heat flux f rom 100 to 150 MW/m(2); the consumption of liquid lithium and a form of lit hium surface are defined; in the second approach Lithium plasma dynamics in invertor is analyzed usin g 2-D MHD divertor code. In this approach heat loads are considerably decre ased by the radiation. Some additional issues connected with utilization of vanadium alloys in Dem o reactor, including environmental and safety aspects, material activation and refabrication were analyzed as well.