Measurement of tritium production rate in water cooled pebble bed multi-layered blanket mockup by DT neutron irradiation experiment

Abstract

For the first time, tritium production rates in the water cooled pebble bed blanket are experimentally examined by using DT neutrons with two partial mockups; multi-layered mockup with water and pebble bed mockup. Tritium production rates (TPRs) are calculated by numerical analyses using Monte Carlo code MCNP-4C with nuclear data libraries FENDL-2.1 and JENDL-3.3. For experimental analysis on the pebble bed mockup, precise modelling method is proposed using the hexagonal close-packed heterogeneous geometry. Prediction uncertainties of TPRs are clarified through the experimental analyses. Ratios of the calculation results to the experimental results on local TPRs are 0.89–1.10 in the multi-layered mockup, and 0.95–1.13 in the pebble bed mockup. The calculation results on integrated tritium productions agree well with the experimental ones in both mockups. It is clarified that integrated tritium productions can be accurately evaluated.

Tritium breeding mock-up experiments containing lithium titanate ceramic pebbles and lead irradiated with DT neutrons

“…The experimental uncertainty in the thermal flux at 1 level is ±4.14% which includes HPGe detector calibration (4%), cross-section uncertainty (0.67%) and statistical error on gamma counts (0.89%). The spectrum averaged cross-section for the reaction 6 Li(n, t) 4 He was evaluated to be 613 b. The triton count rate measured in the SBD detector was 1.42 counts per second (cps).…”

“…Therefore neutronics integral experiments with breeding blanket mock-up are an important research activity to validate the evaluated crosssection data files so that cross-section files can be upgraded and uncertainty in TBR due to cross-sections can be reduced. Several neutronics benchmark experiments with blanket mock-ups are reported in the literature for different breeding blanket concepts [2][3][4][5][6][7][8][9]. India has proposed Lead-Lithium cooled Ceramic Breeder (LLCB) concept of breeding blanket for in situ tritium breeding in its DEMO reactor [10].…”

Measurement of tritium production rate distribution in natural LiAlO2/HDPE assembly irradiated by D-T neutrons

“…In most current designs of DT fusion reactor, Li-containing ceramics such as Li 2 O, LiAlO 2 , LI 2 TiO 3 , Li 2 ZrO 3 and Li 4 SiO 4 are considered to be as the candidates of tritium breeding materials [2][3][4][5][6][7][8][9][10][11]. Few experiments have been conducted to validate the tritium production rate in the breeding assemblies [3][4][5][6][7][8]12].…”

“…Few experiments have been conducted to validate the tritium production rate in the breeding assemblies [3][4][5][6][7][8]12]. A neutronic experiment with the objective to check the prediction capability of neutronic code MCNP and FENDL 2.1 nuclear data library for nuclear responses such as tritium production rate with qualified uncertainties, was designed with LiAlO 2 as breeder and High density polyethylene (HDPE) as neutron reflector.…”

Investigation on the TPR prediction accuracy in blanket neutronics experiments with reflector at JAEA/FNS

“…At the Fusion Neutronics Source (FNS) facility of Japan Atomic Energy Agency (JAEA), a series of blanket neutronics experiments with DT neutrons simulating the WCCB TBM has been carried out for the verification of the prediction accuracy of neutronics performances [2][3][4]. It was demonstrated that the total integrated tritium production in the TBM is predictable within the accuracy of about 10% [3].…”