{"title":"改进有关铀和锆相分配的腔内铈瞬态分层模型","authors":"J. Mativet, A. Lecoanet, R. Le Tellier","doi":"10.1016/j.anucene.2025.111444","DOIUrl":null,"url":null,"abstract":"<div><div>One of the main threats on In-Vessel Melt Retention (IVR) mitigation strategy is the transient thermochemical stratification of the liquid corium in the vessel lowerhead. This paper proposes to improve the modelling of the transient liquid phase stratification of the {U,O,Zr,Steel} system within its miscibility gap. This work is an increment on a previous model considering the metal droplet forming during the relocation, and the focus is here on improving the mass transfer modelling by treating Uranium and Zirconium separately and not as a pseudo component. This means that in the model presented here the molar ratio of Uranium over Zirconium is not equal in the oxide and in the metallic phase.</div><div>The equations of the model are presented as well as the thermodynamic closures it requires. Dissociating the transfers of Uranium and Zirconium allows for the use of thermodynamic closures that are closer to the actual thermodynamic state calculated using a Gibbs Energy minimizer.</div><div>The improved model is applied to a synthetic transient where metal is added on top of an oxide phase leading to an equilibrium state with heavy metal layer creation. This synthetic transient is further modified to reach stratification inversion. The results are compared to the previous model and show significant improvements in computing the transient stratification.</div></div>","PeriodicalId":8006,"journal":{"name":"Annals of Nuclear Energy","volume":"219 ","pages":"Article 111444"},"PeriodicalIF":1.9000,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Improvement of in-vessel corium transient stratification modelling regarding the uranium and zirconium phase partitioning\",\"authors\":\"J. Mativet, A. Lecoanet, R. Le Tellier\",\"doi\":\"10.1016/j.anucene.2025.111444\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>One of the main threats on In-Vessel Melt Retention (IVR) mitigation strategy is the transient thermochemical stratification of the liquid corium in the vessel lowerhead. This paper proposes to improve the modelling of the transient liquid phase stratification of the {U,O,Zr,Steel} system within its miscibility gap. This work is an increment on a previous model considering the metal droplet forming during the relocation, and the focus is here on improving the mass transfer modelling by treating Uranium and Zirconium separately and not as a pseudo component. This means that in the model presented here the molar ratio of Uranium over Zirconium is not equal in the oxide and in the metallic phase.</div><div>The equations of the model are presented as well as the thermodynamic closures it requires. Dissociating the transfers of Uranium and Zirconium allows for the use of thermodynamic closures that are closer to the actual thermodynamic state calculated using a Gibbs Energy minimizer.</div><div>The improved model is applied to a synthetic transient where metal is added on top of an oxide phase leading to an equilibrium state with heavy metal layer creation. This synthetic transient is further modified to reach stratification inversion. The results are compared to the previous model and show significant improvements in computing the transient stratification.</div></div>\",\"PeriodicalId\":8006,\"journal\":{\"name\":\"Annals of Nuclear Energy\",\"volume\":\"219 \",\"pages\":\"Article 111444\"},\"PeriodicalIF\":1.9000,\"publicationDate\":\"2025-04-15\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Annals of Nuclear Energy\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0306454925002610\",\"RegionNum\":3,\"RegionCategory\":\"工程技术\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"NUCLEAR SCIENCE & TECHNOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Annals of Nuclear Energy","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0306454925002610","RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"NUCLEAR SCIENCE & TECHNOLOGY","Score":null,"Total":0}
Improvement of in-vessel corium transient stratification modelling regarding the uranium and zirconium phase partitioning
One of the main threats on In-Vessel Melt Retention (IVR) mitigation strategy is the transient thermochemical stratification of the liquid corium in the vessel lowerhead. This paper proposes to improve the modelling of the transient liquid phase stratification of the {U,O,Zr,Steel} system within its miscibility gap. This work is an increment on a previous model considering the metal droplet forming during the relocation, and the focus is here on improving the mass transfer modelling by treating Uranium and Zirconium separately and not as a pseudo component. This means that in the model presented here the molar ratio of Uranium over Zirconium is not equal in the oxide and in the metallic phase.
The equations of the model are presented as well as the thermodynamic closures it requires. Dissociating the transfers of Uranium and Zirconium allows for the use of thermodynamic closures that are closer to the actual thermodynamic state calculated using a Gibbs Energy minimizer.
The improved model is applied to a synthetic transient where metal is added on top of an oxide phase leading to an equilibrium state with heavy metal layer creation. This synthetic transient is further modified to reach stratification inversion. The results are compared to the previous model and show significant improvements in computing the transient stratification.
期刊介绍:
Annals of Nuclear Energy provides an international medium for the communication of original research, ideas and developments in all areas of the field of nuclear energy science and technology. Its scope embraces nuclear fuel reserves, fuel cycles and cost, materials, processing, system and component technology (fission only), design and optimization, direct conversion of nuclear energy sources, environmental control, reactor physics, heat transfer and fluid dynamics, structural analysis, fuel management, future developments, nuclear fuel and safety, nuclear aerosol, neutron physics, computer technology (both software and hardware), risk assessment, radioactive waste disposal and reactor thermal hydraulics. Papers submitted to Annals need to demonstrate a clear link to nuclear power generation/nuclear engineering. Papers which deal with pure nuclear physics, pure health physics, imaging, or attenuation and shielding properties of concretes and various geological materials are not within the scope of the journal. Also, papers that deal with policy or economics are not within the scope of the journal.