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<front>
<journal-meta>
<journal-id journal-id-type="publisher-id">Front. Energy Res.</journal-id>
<journal-title>Frontiers in Energy Research</journal-title>
<abbrev-journal-title abbrev-type="pubmed">Front. Energy Res.</abbrev-journal-title>
<issn pub-type="epub">2296-598X</issn>
<publisher>
<publisher-name>Frontiers Media S.A.</publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="publisher-id">860553</article-id>
<article-id pub-id-type="doi">10.3389/fenrg.2022.860553</article-id>
<article-categories>
<subj-group subj-group-type="heading">
<subject>Energy Research</subject>
<subj-group>
<subject>Editorial</subject>
</subj-group>
</subj-group>
</article-categories>
<title-group>
<article-title>Editorial: Reactor Fuels, Materials and Systems Under Extreme Environments</article-title>
<alt-title alt-title-type="left-running-head">Zhou et&#x20;al.</alt-title>
<alt-title alt-title-type="right-running-head">Editorial: Extreme Environment Fuels, Materials and Systems</alt-title>
</title-group>
<contrib-group>
<contrib contrib-type="author" corresp="yes">
<name>
<surname>Zhou</surname>
<given-names>Wenzhong</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<xref ref-type="corresp" rid="c001">&#x2a;</xref>
<uri xlink:href="https://loop.frontiersin.org/people/1066467/overview"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Zhang</surname>
<given-names>Chunyu</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<uri xlink:href="https://loop.frontiersin.org/people/1082571/overview"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Huang</surname>
<given-names>Shanfang</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
<uri xlink:href="https://loop.frontiersin.org/people/1482606/overview"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Wu</surname>
<given-names>Zeyun</given-names>
</name>
<xref ref-type="aff" rid="aff3">
<sup>3</sup>
</xref>
<uri xlink:href="https://loop.frontiersin.org/people/1074139/overview"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Revankar</surname>
<given-names>Shripad T.</given-names>
</name>
<xref ref-type="aff" rid="aff4">
<sup>4</sup>
</xref>
<uri xlink:href="https://loop.frontiersin.org/people/79680/overview"/>
</contrib>
</contrib-group>
<aff id="aff1">
<sup>1</sup>
<institution>Sino-French Institute of Nuclear Engineering and Technology</institution>, <institution>Sun Yat-Sen University</institution>, <addr-line>Zhuhai</addr-line>, <country>China</country>
</aff>
<aff id="aff2">
<sup>2</sup>
<institution>Department of Engineering Physics</institution>, <institution>Tsinghua University</institution>, <addr-line>Beijing</addr-line>, <country>China</country>
</aff>
<aff id="aff3">
<sup>3</sup>
<institution>Department of Mechanical and Nuclear Engineering</institution>, <institution>Virginia Commonwealth University</institution>, <addr-line>Richmond</addr-line>, <addr-line>VA</addr-line>, <country>United&#x20;States</country>
</aff>
<aff id="aff4">
<sup>4</sup>
<institution>School of Nuclear Engineering</institution>, <institution>Purdue University</institution>, <addr-line>West Lafayette</addr-line>, <addr-line>IN</addr-line>, <country>United&#x20;States</country>
</aff>
<author-notes>
<fn fn-type="edited-by">
<p>
<bold>Edited by:</bold> <ext-link ext-link-type="uri" xlink:href="https://loop.frontiersin.org/people/758300/overview">Wenxi Tian</ext-link>, Xi&#x2019;an Jiaotong University, China</p>
</fn>
<fn fn-type="edited-by">
<p>
<bold>Reviewed by:</bold> <ext-link ext-link-type="uri" xlink:href="https://loop.frontiersin.org/people/1137804/overview">Di Yun</ext-link>, Xi&#x2019;an Jiaotong University, China</p>
</fn>
<corresp id="c001">&#x2a;Correspondence: Wenzhong Zhou, <email>zhouwzh3@mail.sysu.edu.cn</email>
</corresp>
<fn fn-type="other">
<p>This article was submitted to Nuclear Energy, a section of the journal Frontiers in Energy Research</p>
</fn>
</author-notes>
<pub-date pub-type="epub">
<day>04</day>
<month>03</month>
<year>2022</year>
</pub-date>
<pub-date pub-type="collection">
<year>2022</year>
</pub-date>
<volume>10</volume>
<elocation-id>860553</elocation-id>
<history>
<date date-type="received">
<day>23</day>
<month>01</month>
<year>2022</year>
</date>
<date date-type="accepted">
<day>18</day>
<month>02</month>
<year>2022</year>
</date>
</history>
<permissions>
<copyright-statement>Copyright &#xa9; 2022 Zhou, Zhang, Huang, Wu and Revankar.</copyright-statement>
<copyright-year>2022</copyright-year>
<copyright-holder>Zhou, Zhang, Huang, Wu and Revankar</copyright-holder>
<license xlink:href="http://creativecommons.org/licenses/by/4.0/">
<p>This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these&#x20;terms.</p>
</license>
</permissions>
<related-article id="RA1" related-article-type="commentary-article" journal-id="Front. Cell. Dev. Biol." xlink:href="https://www.frontiersin.org/researchtopic/16333" ext-link-type="uri">Editorial on the Research Topic <article-title>Reactor Fuels, Materials and Systems Under Extreme Environments</article-title>
</related-article>
<kwd-group>
<kwd>experimental/computational fuels and materials</kwd>
<kwd>neutronics</kwd>
<kwd>thermal hydraulics</kwd>
<kwd>severe accident analysis</kwd>
<kwd>two-phase flow</kwd>
</kwd-group>
</article-meta>
</front>
<body>
<p>The safe and economical operation of any nuclear power system relies, to a great extent, on the success of the fuel and the materials of construction (<xref ref-type="bibr" rid="B1">Allen et&#x20;al., 2010</xref>). Distinct from conventional power generation methods, a nuclear reactor is characterized by a harsh level of irradiation, very high operating temperature, and extremely corrosive environments. The behavior of fuels and materials as well as systems for fission reactors is thus complex due to the changes that the extreme environments generate on them. These kinds of changes may be seldom seen in other engineering disciplines, but this poses demanding requirements over reactor fuels, materials and systems. The design of reactor fuels, materials and systems subject to extreme environments is a major obstacle to enhancing reactor safety and economic performance of nuclear power systems. It is also essential in increasing innovation for current reactor operation improvement and future reactor design optimization. To address the challenges related to extreme reactor environments, the team of editors organizes the Research Topic &#x201c;Reactor Fuels, Materials and Systems under Extreme Environments&#x201d; in the journal Frontiers in Energy Research. Finally, 28 articles are collected, covering the theoretical, numerical and experimental studies on reactor fuels, materials and systems under extreme environments.</p>
<p>There are eleven articles about multiphysics/multiscale modeling and simulations of nuclear fuels and materials under extreme reactor environments, for light water reactors, liquid metal cooled fast reactors, and research reactors. In light water reactor studies, <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fenrg.2021.636502/full">Zeng Z. et&#x20;al.</ext-link> present three-dimensional modeling of thermal-mechanical behavior of accident tolerant fuels; <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fenrg.2021.667419/full">Lu W. et&#x20;al.</ext-link> deliver coupled modeling and simulation of phase transformation in zircaloy-4 fuel cladding under loss-of-coolant accident conditions; <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fenrg.2021.677606/full">Liu S. et&#x20;al.</ext-link> work on multiphysics modeling of thorium-based fuel performance with Cr-coated SiC/SiC composite under normal and accident conditions; <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fenrg.2021.691813/full">Yu M. et&#x20;al.</ext-link> show multiphysics investigation on coolant thermohydraulic conditions and fuel rod behavior during a loss-of-coolant accident; <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fenrg.2021.738084/full">Zhang X. et&#x20;al.</ext-link> write 3-dimensional multiphysics modeling of behaviors of pressurized water reactor fuel rods with missing pellet surface; <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fenrg.2021.713493/full">Li X. et&#x20;al.</ext-link> investigate hydrogen atom and molecule adsorptions on FeCrAl (100) surface by a first-principle study. In liquid metal cooled fast reactor investigations, <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fenrg.2021.705944/full">Yuan H. et&#x20;al.</ext-link> contribute lead-cooled fast reactor annular UN fuel design and development of performance analysis program; <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/%2010.3389/fenrg.2021.711916/full">Deng L. et&#x20;al.</ext-link> write multiphysics model development for polonium transport behavior in a lead-cooled fast reactor. <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fenrg.2021.732801/full">Wang G. et&#x20;al.</ext-link> convey preliminary multiphysics performance analysis and design evaluation of UO<sub>2</sub> fuel for LBE-cooled subcritical reactor of China Initiative Accelerator Driven System. Meanwhile, in research reactor approaches, <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fenrg.2021.676881/full">Mao X. et&#x20;al.</ext-link> study the effects of U-Mo irradiation creep performance on the thermo-mechanical coupling behavior in U-Mo/Al monolithic fuel assemblies; <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fenrg.2021.801398/full">Kong X. et&#x20;al.</ext-link> research on macro-mesoscale in-pile thermal-mechanical behavior simulation of a UMo/Zr monolithic fuel&#x20;plate.</p>
<p>Six articles focus on experimental accident tolerant fuels trying to overcome the challenges by the extreme reactor environments from the materials aspect. <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fenrg.2021.655176/full">Ma X. et&#x20;al.</ext-link> investigate elastoplastic deformation and fracture behavior of Cr-coated Zr-4 alloys for accident tolerant fuel claddings; <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fenrg.2021.622708/full">Ma B. et&#x20;al.</ext-link> study friction and wear properties of CrAl-based coatings for nuclear fuel cladding; <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fenrg.2021.663578/full">Lai H. S. et&#x20;al.</ext-link> work on the effect of rolling deformation on creep properties of FeCrAl alloys; <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fenrg.2021.696608/full">Xiong Z. et&#x20;al.</ext-link> present giga-cycle fatigue behavior of the nuclear structure of 316L weldments; <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fenrg.2021.710907/full">Shi T. et&#x20;al.</ext-link> contribute the formation of bubble-loop complexes during helium radiation in Fe-9Cr steel; <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fenrg.2021.735199/full">Huang X. et&#x20;al.</ext-link> show their experimental investigation on the cleaning effect and influence rule of hydrogen peroxide&#x2013;acetic acid on the lead-bismuth eutectic&#x20;alloy.</p>
<p>Six articles emphasize reactor thermal hydraulics, severe accidents, and multiphase flow and heat transfer, which is vital in addressing extreme reactor conditions. <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fenrg.2021.647479/full">Liu Y. et&#x20;al.</ext-link> present their experimental measurement on pebble flow discharge in a hopper silo based on a drainage method; <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fenrg.2021.677865/full">Hao Y. et&#x20;al.</ext-link> deliver a study on the calculation method of molten pool decay heat distribution under IVR condition. <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fenrg.2021.678495/full">Hu P. and Hu Z.</ext-link> contribute a numerical study of the impingement of water film on a small attached bulging plate on a vertical plane; <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fenrg.2021.692627/full">Di Ronco et&#x20;al.</ext-link> theoretically work on an Eulerian single-phase transport model for solid fission products in the molten salt fast reactor to develop an analytical solution for verification purposes; <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fenrg.2021.666032/full">Salmassian B. et&#x20;al.</ext-link> perform a transient parameter analysis of non-scrammed local melting accidents with a VVER 1000 case study; <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fenrg.2021.727447/full">Yang T. et&#x20;al.</ext-link> convey a study on thermophysical properties of a lead&#x2013;bismuth-based graphene nanofluid.</p>
<p>Neutronics and reactor engineering analysis under extreme environments includes three articles. <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fenrg.2021.639416/full">D&#xfc;z M.</ext-link> presents neutronic calculations for certain Americium mixed fuels and clads in a boiling water reactor; <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fenrg.2021.676889/full">Li H. et&#x20;al.</ext-link> introduce an approach to optimize the RMC code Using the decay chain method for large-scale decay calculations; <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fenrg.2021.678262/full">Cai B. et&#x20;al.</ext-link> present a neutronic design for heat pipe reactor with annular and accident tolerant&#x20;fuels.</p>
<p>Finally, this research topic also includes two review articles to overview state-of-the-art research approaches on extreme reactor environments. <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fenrg.2021.669832/full">Li K. et&#x20;al.</ext-link> deliver a review on BeO utilization in reactors for the improvement of extreme reactor environments; <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fenrg.2022.766865/full">Guo J.&#x20;et&#x20;al.</ext-link> contribute a review of models and experiments on fission gas behaviors and relevant phenomena in different nuclear&#x20;fuels.</p>
<p>After almost 1&#xa0;year&#x2019;s revisions and updates, this research topic finally selected those 28 articles and published them in the journal Frontiers in Energy Research. The collection shows the ongoing research on reactor fuels, materials and systems under extreme environments from different perspectives, and also allows us to exhibit the high-quality work to the public. More high-quality topics and articles are welcomed at this open platform in the future. All the editors are open to further information and communications.</p>
</body>
<back>
<sec id="s1">
<title>Author Contributions</title>
<p>All authors listed have made a substantial, direct, and intellectual contribution to the work and approved it for publication.</p>
</sec>
<sec sec-type="COI-statement" id="s2">
<title>Conflict of Interest</title>
<p>The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.</p>
</sec>
<sec sec-type="disclaimer" id="s3">
<title>Publisher&#x2019;s Note</title>
<p>All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.</p>
</sec>
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</article>
