NUCLEAR DATA SENSITIVITY/UNCERTAINTY PRE-ANALYSIS OF FNG WCLL FUSION BENCHMARK

Ivan A Kodeli,Maurizio Angelone,Davide Flamini

doi:10.1051/epjconf/202124715004

Abstract

To assure tritium self-sufficiency in future fusion reactors such as DEMO the accuracy of TRP calculations has to be demonstrated within the design uncertainties. A new neutronics experiment representing a mock-up of the Water Cooled Lithium Lead (WCLL) Test Blanket Module (TBM) is under preparation at the Frascati neutron generator (FNG) with the objective to provide an experimental validation of accuracy of nuclear data and neutron transport codes for the tritium production rate (TPR) calculations. The mock-up will consist of LiPb bricks, EUROFER plates and Perspex substituting water. The mock-up will be irradiated by 14 MeV neutrons at the FNG facility, and the TPR and detector reaction rates will be measured using Li2CO3 pellets and activation foils placed at different positions up to about 55 cm inside the mock-up. Computational pre-analyses for the design of the WCLL neutronics experiment using the SUSD3D sensitivity/uncertainty (S/U) code system is described and compared with the results of some similar FNG experiments performed in the past, in particular the FNG HCPB Tritium Breeder Module Mock-up (2005) and FNG-HCLL Tritium Breeder Module Mock-up (2009). The objective of the pre-analysis is to provide the calculated nuclear responses including the uncertainties due to the uncertainties in nuclear data and thus contributes to the optimisation of the design of the experimental set-up.

Highlights

Since 20+ years a series of neutronics benchmark experiments have been performed at the Frascati neutron generator (FNG) of ENEA Frascati in the scope of the European fusion programme [1,2,3,4,5,6,7]
A new neutronics experiment representing a mock-up of the Water Cooled Lithium Lead (WCLL) Test Blanket Module (TBM) [8] is under preparation at the FNG facility with the objective to experimentally validate the capability of the neutronics codes and nuclear data to predict the tritium production rate (TPR) and other nuclear responses within the design uncertainties
Computational pre-analyses for the design of the WCLL neutronics experiment using the SUSD3D sensitivity and uncertainty (S/U) code system was performed to assess the uncertainty in tritium production rate (TPR) due to the uncertainty in the relevant nuclear data and compared with the results of some similar FNG experiments performed in the past, in particular the FNG-HCLL Tritium Breeder Module Mock-up (2009)

Summary

INTRODUCTION

Since 20+ years a series of neutronics benchmark experiments have been performed at the Frascati neutron generator (FNG) of ENEA Frascati in the scope of the European fusion programme [1,2,3,4,5,6,7]. A new neutronics experiment representing a mock-up of the Water Cooled Lithium Lead (WCLL) TBM [8] is under preparation at the FNG facility with the objective to experimentally validate the capability of the neutronics codes and nuclear data to predict the tritium production rate (TPR) and other nuclear responses within the design uncertainties. As in the above mentioned cases, the mock-up will be irradiated by 14 MeV neutrons at the FNG facility, and the TPR and detector reaction rates will be measured using Li2CO3 pellets (containing both natural and 6Li-enriched lithium) and activation foils placed at various positions inside the mock-up. The reference neutron transport calculations were performed with the MCNP6 code accelerated using weight window parameters

SENSITIVITY-UNCERTAINTY ANALYSIS

Cross-section sensitivity analysis

Cross section uncertainty analysis

Findings

CONCLUSIONS