Investigation on the Effect of Tritium Breeding Ratio Using Temperature Control Mechanism for DEMO Blanket

The tritium breeding ratio (TBR) is a key parameter to assess the tritium self-sufficiency of the tritium fuel cycle system for a demonstrate power plant reactor (DEMO reactor). In this paper, a new approach on the TBR optimization of breeding blanket is developed based on the temperature control mechanism theory considering the variation of the blanket structural parameters. The local TBR issues are explored based on a pressurized water-cooled reactor (PWR) blanket module. The blanket materials volume ratio issues are studied to support the blanket structure optimization. The TBR variation is presented with the change of blanket internal structural parameters, including the pipe bore, the pipe pitch, and so on, via the blanket temperature field control approach. It is found that the pipe bore and the pipe pitch should be considered simultaneously in the blanket design to ensure a reasonable temperature field. It indicates that any of the blanket structure changes, including pipe bore, pipe pitch, and so on, will lead to the material volume ratio rise or reduction, which can cause the local TBR variation accordingly. And the results confirm that the pipe bore with 9 mm will achieve the maximum TBR for the blanket module. It is concluded that TBR is affected by the blanket temperature field dynamical variation through the temperature regulation in considering the tritium release and the recovery.