Utilization of fusion neutrons very high energy effects in the design of a fusion reactor tritium breeding blanket

Tritium needed for ITER fusion reactions can be regenerated in a blanket located in the tokamak. Such breeding has to be achieved through special interactions between very high energy (14.1 MeV) fusion neutrons and the blanket materials, like the lithium-7 tritium breeding effect and the thorium-232 neutron multiplication effect, all this while occupying the smallest possible space. Five blankets were designed and investigated; three of them were purely composed of lithium materials, while the two others were designed by adding a thorium layer before the lithium layer. A 3-D modeling was created using a Monte Carlo N-particle Code (MCNP) to simulate the fusion neutrons histories through the tritium breeding blankets, with a blanket thickness ranging from 1 cm to 200 cm. The minimum blanket thickness necessary to obtain a tritium breeding ratio (TBR) greater than one ranges from 20 cm to 45 cm. In particular, the Lithium Oxide Mono-Layer Blanket (LO-MLB) achieves a TBR greater than one while allowing blanket thickness to stay under 25 cm, thus making it the most efficient blanket in this sample. Second, the maximum TBR for thick blankets ranges from 1.5 to 2. In particular, the Natural Lithium Mono-Layer Blanket (NL-MLB) displays the highest maximum TBR thanks to its perfect combination of the lithium-7 and lithium-6 tritium breeding capacity. (author)