Study of a spherical torus based volumetric neutron source for nuclear technology testing and development

A plasma based, deuterium and tritium (DT) fueled, volumetric 14 MeV neutro n source (VNS) has been considered as a possible facility to support the de velopment of the demonstration fusion power reactor (DEMO). It can be used to test and develop necessary fusion blanket and divertor components and pr ovide sufficient database, particularly on the reliability of nuclear compo nents necessary for DEMO. The VNS device can be complement to ITER by reduc ing the cost and risk in the development of DEMO. A low cost, scientificall y attractive, and technologically feasible volumetric neutron source based on the spherical torus (ST) concept has been conceived. The ST-VNS, which h as a major radius of 1.07 m, aspect ratio 1.4, and plasma elongation three, can produce a neutron wall loading from 0.5 to 5 MW m (2) at the outboard test section with a modest fusion power level from 38 to 380 MW. It can be used to test necessary nuclear technologies for fusion power reactor and de velop fusion core components include divertor, first wall, and power blanke t. Using staged operation leading to high neutron wall loading and optimist ic availability, a neutron fluence of more than 30 MW year m(-2) is obtaina ble within 20 years of operation. This will permit the assessments of lifet ime and reliability of promising fusion core components in a reactor releva nt environment. A full scale demonstration of power reactor fusion core com ponents is also made possible because of the high neutron wall loading capa bility. Tritium breeding in such a full scale demonstration can be very use ful to ensure the self-sufficiency of fuel cycle for a candidate power blan ket concept. (C) 2000 Elsevier Science S.A. All rights reserved.