1
|
Grizzi VF, Lee SC, Z Y. First-Principles Investigation of the Effects of UF 4 and ThF 4 Fuels on the Structural, Dynamic, and Thermodynamic Properties of LiF-NaF. J Phys Chem B 2024; 128:5676-5684. [PMID: 38831744 DOI: 10.1021/acs.jpcb.4c01243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2024]
Abstract
An in-depth understanding and characterization of molten salt properties are necessary for the optimized design, efficient operation, and safety assurance of molten salt reactors (MSRs). Investigating molten salt properties in experimental settings can be challenging and time-consuming due to the high temperatures of interest, the salt's corrosiveness, purity and composition control, and health and safety concerns. Therefore, it is beneficial to perform computational screening to assist in the ultimate experimental measurements. Herein, we used first-principles molecular dynamics simulations to calculate several thermophysical, structural, and dynamic properties of eutectic LiF-NaF with fuel additives UF4 and ThF4. We found that with the incorporation of uranium or thorium, a prepeak appears in the structure factor, indicative of a medium-range structural ordering. Furthermore, we explore the mechanism through which these structural changes enhance shear stress correlations, thereby increasing the salt's viscosity. This work highlights the importance of studying the atomic-scale structure of molten salts and how the addition of fuel elements can substantially affect it.
Collapse
Affiliation(s)
- Vitor F Grizzi
- Department of Nuclear, Plasma, and Radiological Engineering, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Shao-Chun Lee
- Department of Nuclear, Plasma, and Radiological Engineering, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Y Z
- Department of Nuclear, Plasma, and Radiological Engineering, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, United States
- Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Robotics, University of Michigan, Ann Arbor, Michigan 48109, United States
| |
Collapse
|
2
|
Gharakhanyan V, Wirth LJ, Garrido Torres JA, Eisenberg E, Wang T, Trinkle DR, Chatterjee S, Urban A. Discovering melting temperature prediction models of inorganic solids by combining supervised and unsupervised learning. J Chem Phys 2024; 160:204112. [PMID: 38804486 DOI: 10.1063/5.0207033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Accepted: 04/29/2024] [Indexed: 05/29/2024] Open
Abstract
The melting temperature is important for materials design because of its relationship with thermal stability, synthesis, and processing conditions. Current empirical and computational melting point estimation techniques are limited in scope, computational feasibility, or interpretability. We report the development of a machine learning methodology for predicting melting temperatures of binary ionic solid materials. We evaluated different machine-learning models trained on a dataset of the melting points of 476 non-metallic crystalline binary compounds using materials embeddings constructed from elemental properties and density-functional theory calculations as model inputs. A direct supervised-learning approach yields a mean absolute error of around 180 K but suffers from low interpretability. We find that the fidelity of predictions can further be improved by introducing an additional unsupervised-learning step that first classifies the materials before the melting-point regression. Not only does this two-step model exhibit improved accuracy, but the approach also provides a level of interpretability with insights into feature importance and different types of melting that depend on the specific atomic bonding inside a material. Motivated by this finding, we used a symbolic learning approach to find interpretable physical models for the melting temperature, which recovered the best-performing features from both prior models and provided additional interpretability.
Collapse
Affiliation(s)
- Vahe Gharakhanyan
- Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027, USA
- Columbia Electrochemical Energy Center, Columbia University, New York, New York 10027, USA
| | - Luke J Wirth
- Department of Materials Science and Engineering, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Jose A Garrido Torres
- Department of Chemical Engineering, Columbia University, New York, New York 10027, USA
| | - Ethan Eisenberg
- Department of Chemical Engineering, Columbia University, New York, New York 10027, USA
| | - Ting Wang
- Department of Chemical Engineering, Columbia University, New York, New York 10027, USA
| | - Dallas R Trinkle
- Department of Materials Science and Engineering, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, USA
| | | | - Alexander Urban
- Columbia Electrochemical Energy Center, Columbia University, New York, New York 10027, USA
- Department of Chemical Engineering, Columbia University, New York, New York 10027, USA
| |
Collapse
|
3
|
Porter T, Vaka MM, Steenblik P, Della Corte D. Computational methods to simulate molten salt thermophysical properties. Commun Chem 2022; 5:69. [PMID: 36697757 PMCID: PMC9814384 DOI: 10.1038/s42004-022-00684-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 05/11/2022] [Indexed: 01/28/2023] Open
Abstract
Molten salts are important thermal conductors used in molten salt reactors and solar applications. To use molten salts safely, accurate knowledge of their thermophysical properties is necessary. However, it is experimentally challenging to measure these properties and a comprehensive evaluation of the full chemical space is unfeasible. Computational methods provide an alternative route to access these properties. Here, we summarize the developments in methods over the last 70 years and cluster them into three relevant eras. We review the main advances and limitations of each era and conclude with an optimistic perspective for the next decade, which will likely be dominated by emerging machine learning techniques. This article is aimed to help researchers in peripheral scientific domains understand the current challenges of molten salt simulation and identify opportunities to contribute.
Collapse
Affiliation(s)
- Talmage Porter
- grid.253294.b0000 0004 1936 9115Department of Physics and Astronomy, Brigham Young University, Provo, UT USA
| | - Michael M. Vaka
- grid.253294.b0000 0004 1936 9115Department of Physics and Astronomy, Brigham Young University, Provo, UT USA
| | - Parker Steenblik
- grid.253294.b0000 0004 1936 9115Department of Physics and Astronomy, Brigham Young University, Provo, UT USA
| | - Dennis Della Corte
- grid.253294.b0000 0004 1936 9115Department of Physics and Astronomy, Brigham Young University, Provo, UT USA
| |
Collapse
|
4
|
Lam ST, Li QJ, Ballinger R, Forsberg C, Li J. Modeling LiF and FLiBe Molten Salts with Robust Neural Network Interatomic Potential. ACS APPLIED MATERIALS & INTERFACES 2021; 13:24582-24592. [PMID: 34019760 DOI: 10.1021/acsami.1c00604] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Lithium-based molten salts have attracted significant attention due to their applications in energy storage, advanced fission reactors, and fusion devices. Lithium fluorides and particularly 66.6%LiF-33.3%BeF2 (Flibe) are of considerable interest in nuclear systems, as they show an excellent combination of favorable heat transfer, neutron moderation, and transmutation characteristics. For nuclear salts, the range of possible local structures, compositions, and thermodynamic conditions presents significant challenges in atomistic modeling. In this work, we demonstrate that atom-centered neural network interatomic potentials (NNIPs) provide a fast method for performing molecular dynamics of molten salts that is as accurate as ab initio molecular dynamics. For LiF, these potentials are able to accurately reproduce ab initio interactions of dimers, crystalline solids under deformation, crystalline LiF near the melting point, and liquid LiF at high temperatures. For Flibe, NNIPs accurately predict the structures and dynamics at normal operating conditions, high-temperature-pressure conditions, and in the crystalline solid phase. Furthermore, we show that NNIP-based molecular dynamics of molten salts are scalable to reach long time scales (e.g., nanosecond) and large system sizes (e.g., 105 atoms) while maintaining ab initio density functional theory accuracy and providing more than 3 orders of magnitude of computational speedup for calculating structure and transport properties.
Collapse
Affiliation(s)
- Stephen T Lam
- Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, Massachusetts 01854, United States
- Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Qing-Jie Li
- Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Ronald Ballinger
- Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Charles Forsberg
- Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Ju Li
- Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| |
Collapse
|
5
|
Serva A, Guerault A, Ishii Y, Gouillart E, Burov E, Salanne M. Structural and dynamic properties of soda–lime–silica in the liquid phase. J Chem Phys 2020; 153:214505. [DOI: 10.1063/5.0029702] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Affiliation(s)
- Alessandra Serva
- Sorbonne Université, CNRS, Physico-Chimie des Electrolytes et Nanosystèmes Interfaciaux, PHENIX, F-75005 Paris, France
| | - Allan Guerault
- Sorbonne Université, CNRS, Physico-Chimie des Electrolytes et Nanosystèmes Interfaciaux, PHENIX, F-75005 Paris, France
- Surface du Verre et Interface (UMR 125), CNRS/Saint-Gobain Research Paris, 39 quai Lucien Lefranc, 93300 Aubervilliers, France
| | - Yoshiki Ishii
- Graduate School of Simulation Studies, University of Hyogo, 7-1-28 Minatojima-Minamimachi, Chuo-ku, Kobe, Hyogo 650-0047, Japan
- Elements Strategy Initiative for Catalysts and Batteries, Kyoto University, Katsura, Kyoto 615-8520, Japan
| | - Emmanuelle Gouillart
- Surface du Verre et Interface (UMR 125), CNRS/Saint-Gobain Research Paris, 39 quai Lucien Lefranc, 93300 Aubervilliers, France
| | - Ekaterina Burov
- Surface du Verre et Interface (UMR 125), CNRS/Saint-Gobain Research Paris, 39 quai Lucien Lefranc, 93300 Aubervilliers, France
| | - Mathieu Salanne
- Sorbonne Université, CNRS, Physico-Chimie des Electrolytes et Nanosystèmes Interfaciaux, PHENIX, F-75005 Paris, France
- Institut Universitaire de France (IUF), 75231 Paris Cedex 05, France
| |
Collapse
|
6
|
Bučko T, Šimko F. On the structure of crystalline and molten cryolite: Insights from the ab initio molecular dynamics in NpT ensemble. J Chem Phys 2016; 144:064502. [DOI: 10.1063/1.4941333] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Tomáš Bučko
- Department of Physical and Theoretical Chemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, SK-84215 Bratislava, Slovakia
- Institute of Inorganic Chemistry, Slovak Academy of Sciences, Dúbravská Cesta 9, SK-84236 Bratislava, Slovakia
| | - František Šimko
- Institute of Inorganic Chemistry, Slovak Academy of Sciences, Dúbravská Cesta 9, SK-84236 Bratislava, Slovakia
| |
Collapse
|