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Title: MARMOT Phase-Field Model for the U-Si System

Abstract

A phase-field model for the U-Si system has been implemented in MARMOT. The free energies for the phases relevant to accident-tolerant fuel applications (U 3Si 2, USi, U 3Si, and liquid) were implemented as free energy materials within MARMOT. A new three-phase phase-field model based on the concepts of the Kim-Kim-Suzuki two-phase model was developed and implemented in the MOOSE phase-field module. Key features of this model are that two-phase interfaces are stable with respect to formation of the third phase, and that arbitrary phase free energies can be used. The model was validated using a simplified three-phase system and the U-Si system. In the U-Si system, the model correctly reproduced three-phase coexistence in a U 3Si 2-liquid-USi system at the eutectic temperature, solidification of a three-phase mixture below the eutectic temperature, and complete melting of a three-phase mixture above the eutectic temperature.

Authors:
 [1];  [1]
  1. Idaho National Lab. (INL), Idaho Falls, ID (United States)
Publication Date:
Research Org.:
Idaho National Lab. (INL), Idaho Falls, ID (United States)
Sponsoring Org.:
USDOE Office of Nuclear Energy (NE)
OSTI Identifier:
1389724
Report Number(s):
INL/EXT-16-39970
DOE Contract Number:
AC07-05ID14517
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; FREE ENERGY; EUTECTICS; MARMOT; Phase-Field; Silicon; U-Si; U3Si2; Uranium

Citation Formats

Aagesen, Larry Kenneth, and Schwen, Daniel. MARMOT Phase-Field Model for the U-Si System. United States: N. p., 2016. Web. doi:10.2172/1389724.
Aagesen, Larry Kenneth, & Schwen, Daniel. MARMOT Phase-Field Model for the U-Si System. United States. doi:10.2172/1389724.
Aagesen, Larry Kenneth, and Schwen, Daniel. 2016. "MARMOT Phase-Field Model for the U-Si System". United States. doi:10.2172/1389724. https://www.osti.gov/servlets/purl/1389724.
@article{osti_1389724,
title = {MARMOT Phase-Field Model for the U-Si System},
author = {Aagesen, Larry Kenneth and Schwen, Daniel},
abstractNote = {A phase-field model for the U-Si system has been implemented in MARMOT. The free energies for the phases relevant to accident-tolerant fuel applications (U3Si2, USi, U3Si, and liquid) were implemented as free energy materials within MARMOT. A new three-phase phase-field model based on the concepts of the Kim-Kim-Suzuki two-phase model was developed and implemented in the MOOSE phase-field module. Key features of this model are that two-phase interfaces are stable with respect to formation of the third phase, and that arbitrary phase free energies can be used. The model was validated using a simplified three-phase system and the U-Si system. In the U-Si system, the model correctly reproduced three-phase coexistence in a U3Si2-liquid-USi system at the eutectic temperature, solidification of a three-phase mixture below the eutectic temperature, and complete melting of a three-phase mixture above the eutectic temperature.},
doi = {10.2172/1389724},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2016,
month = 9
}

Technical Report:

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