Density functional theory calculations of defect and fission gas properties in U-Si fuels
Abstract
Accident tolerant fuels (ATF) are being developed in response to the Fukushima Daiichi accident in Japan. One of the options being pursued is U-Si fuels, such as the U 3Si 2 and U 3Si 5 compounds, which benefit from high thermal conductivity (metallic) compared to the UO 2 fuel (insulator or semi-conductor) used in current Light Water Reactors (LWRs). The U-Si fuels also have higher fissile density. In order to perform meaningful engineering scale nuclear fuel performance simulations, the material properties of the fuel, including the response to irradiation environments, must be known. Unfortunately, the data available for U-Si fuels are rather limited, in particular for the temperature range where LWRs would operate. The ATF HIP is using multi-scale modeling and simulations to address this knowledge gap. The present study investigates point defect and fission gas properties in U 3Si 2, which is one of the main fuel candidates, using density functional theory (DFT) calculations. Based on a few assumption regarding entropy contributions, defect and fission diffusivities are predicted. Even though uranium silicides have been shown to amorphize easily at low temperature, we assume that U 3Si 2 remains crystalline under the conditions expected in Light Water Reactors (LWRs). Themore »
- Authors:
-
- Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
- Publication Date:
- Research Org.:
- Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
- Sponsoring Org.:
- USDOE
- OSTI Identifier:
- 1237246
- Report Number(s):
- LA-UR-15-27996
TRN: US1600299
- DOE Contract Number:
- AC52-06NA25396
- Resource Type:
- Technical Report
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS; ACCIDENT-TOLERANT NUCLEAR FUELS; URANIUM SILICIDES; DENSITY FUNCTIONAL METHOD; FISSION PRODUCTS; WATER MODERATED REACTORS; WATER COOLED REACTORS; URANIUM DIOXIDE; POINT DEFECTS; THERMAL CONDUCTIVITY; ENTROPY; COMPARATIVE EVALUATIONS; DENSITY; DIFFUSION; COMPUTERIZED SIMULATION; AMORPHOUS STATE; IRRADIATION; PERFORMANCE; PHYSICAL RADIATION EFFECTS
Citation Formats
Andersson, Anders David. Density functional theory calculations of defect and fission gas properties in U-Si fuels. United States: N. p., 2016.
Web. doi:10.2172/1237246.
Andersson, Anders David. Density functional theory calculations of defect and fission gas properties in U-Si fuels. United States. doi:10.2172/1237246.
Andersson, Anders David. Wed .
"Density functional theory calculations of defect and fission gas properties in U-Si fuels". United States.
doi:10.2172/1237246. https://www.osti.gov/servlets/purl/1237246.
@article{osti_1237246,
title = {Density functional theory calculations of defect and fission gas properties in U-Si fuels},
author = {Andersson, Anders David},
abstractNote = {Accident tolerant fuels (ATF) are being developed in response to the Fukushima Daiichi accident in Japan. One of the options being pursued is U-Si fuels, such as the U3Si2 and U3Si5 compounds, which benefit from high thermal conductivity (metallic) compared to the UO2 fuel (insulator or semi-conductor) used in current Light Water Reactors (LWRs). The U-Si fuels also have higher fissile density. In order to perform meaningful engineering scale nuclear fuel performance simulations, the material properties of the fuel, including the response to irradiation environments, must be known. Unfortunately, the data available for U-Si fuels are rather limited, in particular for the temperature range where LWRs would operate. The ATF HIP is using multi-scale modeling and simulations to address this knowledge gap. The present study investigates point defect and fission gas properties in U3Si2, which is one of the main fuel candidates, using density functional theory (DFT) calculations. Based on a few assumption regarding entropy contributions, defect and fission diffusivities are predicted. Even though uranium silicides have been shown to amorphize easily at low temperature, we assume that U3Si2 remains crystalline under the conditions expected in Light Water Reactors (LWRs). The temperature and dose where amorphization occurs has not yet been well established.},
doi = {10.2172/1237246},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Feb 03 00:00:00 EST 2016},
month = {Wed Feb 03 00:00:00 EST 2016}
}