Moving toroidal limiter

Abstract The concept of the limiter-divertor proposed by Mirnov [1] is extended to a toroidal limiter-divertor (which we call a moving toroidal limiter) using a stream of ferromagnetic balls coated with low Z materials such as plastics, graphite or ceramics. The important advantage of the use of the ferromagnetic materials would be the possible soft landing of the balls on a catcher, provided that the temperature of the balls is below Curie point. Moreover, a moving toroidal limiter would work as a protector of the first wall against the vertical movement of plasma ring and the violent inward motion driven by major disruption. This is because the orbit of the ball in the case of moving toroidal limiter extends over the small major radius side of the toroidal plasma. In addition, it is suggested that the moving balls can remove the heat from the divertor chamber instead of using the standard divertor plates.