Nuclear aspects of the ITER [International Thermonuclear Experimental Reactor] design

The engineering and testing objectives of the International Thermonuclear Experimental Reactor (ITER) are (a) to validate design concepts and qualify engineering components, (b) to demonstrate the reliability and maintainability of the reactor systems, and (c) to test the main nuclear technologies (blanket modules, tritium production, extraction of high-grade heat appropriate for the generation of electricity). Specifically, it is hoped that the ITER device can provide (a) testing conditions with an average neutron wall loading of ∼1 MW/m2, (b) a neutron fluence of ∼1 MW·yr/m2 but with the design allowing for the possibility for a higher neutron fluence in the 3 MW·yr/m2 range, (c) a tritium breeding blanket that seeks to achieve a breeding ratio as close to unity as possible, and (d) an overall availability of the ITER of at least 10%, but which should reach a level of 25% and provide continuous operation for a period lasting 1 to 2 weeks. This paper summarizes the progress of nuclear aspects of the ITER program