A new methodology for thermal analysis of geological disposal of spent nuclear fuel using integrated simulations of gamma heating and finite element modeling. (July 2022)

• Record Type: Journal Article
• Authors: Jansson, Peter; Renström, Peter; Sarnet, Jan; Sjöland, Anders
• Is Part Of: Annals of nuclear energy. Volume 172(2022)
• Publication Date: 2022-07
• Subjects: Thermal model -- Gamma heating -- KBS-3 -- Geological disposal -- Nuclear fuel -- Decay heat -- Temperature -- Monte Carlo -- Geant4 -- FEM; Nuclear energy -- Periodicals; Nuclear engineering -- Periodicals; 621.4805
• DOI: 10.1016/j.anucene.2022.109082
• Languages: English
• ISSNs: 0306-4549

Abstract

Highlights: Temperature evolution in geological disposal of spent nuclear fuel is estimated. Spatially distributed gamma heating is the heat source in finite element modeling. For one specific case, the model showed small impact on the temperature distribution. Small decrease of maximum temperature compared to conventional modeling. Abstract: A new methodology is illustrated, where the evolution of temperature in a geological disposal system for spent nuclear fuel is estimated by integrated calculations of a spatially distributed gamma heating source with conventional finite element thermal transport modeling. A case with one canister loaded with fuel assemblies with a cooling time of 30 years in a KBS-3 type repository illustrates the methodology. For this particular case, the effect of including distributed gamma heating rate in the modeling has a small impact on the temperature distribution compared to the conventional case of heat generated locally in the canister, resulting in a small decrease of the maximum temperature in the canister. A large proportion of gamma heating occurs inside the outer boundary of the copper canister for this case. Other potential consequences of radiation escaping the canister are discussed.