A high-fluence fusion neutron source

Abstract

Abstract A conceptual design of a D—T fusion facility for the continuous production of 14 MeV neutron wall loading from 5 to 10 MW/m 2 at the plasma surface is presented. In this design, D—T neutrons are produced in a linear, two-component plasma formed by neutral beam irradiation of a fully ionized warm plasma target. The beam energy, which is deposited in the center, is transferred to the warm plasma mainly by electron drag and is conducted along the target plasma column to end regions where it is absorbed in neutral gas at high pressure. The target plasma is operated in a regime where electron thermal conduction along the column is the controlling energy-loss process. The loss rate is minimized by adjusting the diameter and length of the plasma column. A substantial gradient in T e along the column results in recombination of the plasma to gas in the end regions before impact on the end walls. The resultant hot gas is cooled by contact with large-area heat exchangers. In this way, the large steady-state heat load from the injected neutral beams is diffused and removed at tolerable heat flux levels. The reacting plasma is essentially an extrapolation of the 2XIIB high-β plasma to higher magnetic field, ion energy, and density.