Passively safe tandem mirror fusion blanket afterheat thermal analysis

This paper presents results of the thermal analysis of an inherently safe blanket design concept. The blanket is composed of V-15Cr-5Ti structure with lithium for tritium breeding, beryllium for neutron multiplication and SiC for neutron reflection and moderation. Cooling of the blanket is provided by flowing helium gas which is assumed to be unavailable for heat transfer during the accident. The blanket afterheat temperature response was calculated using the SINDA thermal analysis code. Afterheat source values were calculated separately and input as spacially and time varying quantities for each blanket zone. Results indicate that the first wall temperature will peak at 709/sup 0/C in about 1 1/2 days and that the blanket will reach 760/sup 0/C in one year. Any cooling, by convection to the reactor building atmosphere, for example, will reduce these temperatures. Our analysis indicates that this blanket can be left unattended and uncooled at shutdown.