An online method to measure tritium production rate of fusion -fission hybrid reactor in CAEP

As an important parameter of neutronics integral experiment, tritium production rate could not only be used for validation of programs and evaluation database, but was also related to tritium self-consistency after the activation of the sub-critical reactor. This parameter was a key component of the sub-critical reactor design. Four blanket benchmark mockups of a fusion-fission hybrid reactor were established utilizing lithium materials, which consisted of depleted uranium/lithium hydride, uranium/lithium hydride/polyethylene, uranium/lithium hydride/graphite/iron, and uranium/Li-Pb alloy/polyethylene. Based on the Cockcroft Walton neutron generator, the distribution of tritium production rate by D T neutrons in the four mockups was evaluated by two pairs of different sizes lithium glass detectors. The distribution was then quantitatively assessed using MCNP5 program and ENDF/B-VII database. The tritium production rates of the mockups with lithium hydride significantly deviated from the experimental results; whereas those of the mockup with lithium-lead alloy were agree well with the experimental results.