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<article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:ali="http://www.niso.org/schemas/ali/1.0/" article-type="research-article" dtd-version="1.2" xml:lang="en"><front><journal-meta><journal-id journal-id-type="publisher-id">Contemporary Mathematics. Fundamental Directions</journal-id><journal-title-group><journal-title xml:lang="en">Contemporary Mathematics. Fundamental Directions</journal-title><trans-title-group xml:lang="ru"><trans-title>Современная математика. Фундаментальные направления</trans-title></trans-title-group></journal-title-group><issn publication-format="print">2413-3639</issn><issn publication-format="electronic">2949-0618</issn><publisher><publisher-name xml:lang="en">Peoples’ Friendship University of Russia named after Patrice Lumumba (RUDN University)</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="publisher-id">48175</article-id><article-id pub-id-type="doi">10.22363/2413-3639-2025-71-4-686-700</article-id><article-id pub-id-type="edn">MKADHS</article-id><article-categories><subj-group subj-group-type="toc-heading" xml:lang="en"><subject>Articles</subject></subj-group><subj-group subj-group-type="toc-heading" xml:lang="ru"><subject>Статьи</subject></subj-group><subj-group subj-group-type="article-type"><subject>Research Article</subject></subj-group></article-categories><title-group><article-title xml:lang="en">Dynamics of the conformation tensor in viscoelastic FENE polymer models</article-title><trans-title-group xml:lang="ru"><trans-title>Динамика тензора конформации в вязкоупругих моделях полимеров FENE</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-9492-5527</contrib-id><contrib-id contrib-id-type="scopus">55910100800</contrib-id><contrib-id contrib-id-type="researcherid">AIA-3732-2022</contrib-id><contrib-id contrib-id-type="spin">7023-4994</contrib-id><name-alternatives><name xml:lang="en"><surname>Chupakhin</surname><given-names>A. P.</given-names></name><name xml:lang="ru"><surname>Чупахин</surname><given-names>А. П.</given-names></name></name-alternatives><email>chupakhin@hydro.nsc.ru</email><xref ref-type="aff" rid="aff1"/><xref ref-type="aff" rid="aff2"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Stetsyak</surname><given-names>E. S.</given-names></name><name xml:lang="ru"><surname>Стецяк</surname><given-names>Е. С.</given-names></name></name-alternatives><email>stetsyak.e.s@hydro.nsc.ru</email><xref ref-type="aff" rid="aff1"/><xref ref-type="aff" rid="aff2"/><xref ref-type="aff" rid="aff3"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Chutkov</surname><given-names>D. S.</given-names></name><name xml:lang="ru"><surname>Чутков</surname><given-names>Д. С.</given-names></name></name-alternatives><email>d.chutkov@g.nsu.ru</email><xref ref-type="aff" rid="aff2"/></contrib></contrib-group><aff-alternatives id="aff1"><aff><institution xml:lang="en">Lavrentyev Institute of Hydrodynamics SB RAS</institution></aff><aff><institution xml:lang="ru">Институт гидродинамики им. М.А. Лаврентьева СО РАН</institution></aff></aff-alternatives><aff-alternatives id="aff2"><aff><institution xml:lang="en">Novosibirsk National Research State University</institution></aff><aff><institution xml:lang="ru">Новосибирский государственный университет</institution></aff></aff-alternatives><aff-alternatives id="aff3"><aff><institution xml:lang="en">Skolkovo Institute of Science and Technology</institution></aff><aff><institution xml:lang="ru">Сколковский институт науки и технологий</institution></aff></aff-alternatives><pub-date date-type="pub" iso-8601-date="2025-12-25" publication-format="electronic"><day>25</day><month>12</month><year>2025</year></pub-date><volume>71</volume><issue>4</issue><issue-title xml:lang="en">VOL 71, NO3 (2025)</issue-title><issue-title xml:lang="ru">ТОМ 71, №4 (2025)</issue-title><fpage>686</fpage><lpage>700</lpage><history><date date-type="received" iso-8601-date="2026-01-21"><day>21</day><month>01</month><year>2026</year></date></history><permissions><copyright-statement xml:lang="en">Copyright ©; 2025, Chupakhin A.P., Stetsyak E.S., Chutkov D.S.</copyright-statement><copyright-statement xml:lang="ru">Copyright ©; 2025, Чупахин А.П., Стецяк Е.С., Чутков Д.С.</copyright-statement><copyright-year>2025</copyright-year><copyright-holder xml:lang="en">Chupakhin A.P., Stetsyak E.S., Chutkov D.S.</copyright-holder><copyright-holder xml:lang="ru">Чупахин А.П., Стецяк Е.С., Чутков Д.С.</copyright-holder><ali:free_to_read xmlns:ali="http://www.niso.org/schemas/ali/1.0/"/><license><ali:license_ref xmlns:ali="http://www.niso.org/schemas/ali/1.0/">https://creativecommons.org/licenses/by-nc/4.0</ali:license_ref></license></permissions><self-uri xlink:href="https://journals.rudn.ru/CMFD/article/view/48175">https://journals.rudn.ru/CMFD/article/view/48175</self-uri><abstract xml:lang="en"><p>In this work, the equations for the dynamics of the invariants of the conformational tensor for FENE polymer solution models are derived and integrated. Explicit formulas for the invariants as functions of the time parameter along the trajectory of fluid particles are obtained. The invariants are represented as functions of the Lambert function. A description of the qualitative behavior of the invariants under different regimes is given.</p></abstract><trans-abstract xml:lang="ru"><p>В настоящей работе получены и проинтегрированы уравнения, описывающие эволюцию инвариантов тензора конформации для модели FENE вязкоупругого полимерного раствора. Найдены явные выражения инвариантов в зависимости от времени вдоль траекторий частиц жидкости. Указанные инварианты представлены в виде функций от функции Ламберта. Проведён анализ качественного поведения инвариантов в различных режимах деформирования.</p></trans-abstract><kwd-group xml:lang="en"><kwd>FENE polymer equations</kwd><kwd>Lie derivative</kwd><kwd>invariants of the conformational tensor</kwd><kwd>integration of equations</kwd></kwd-group><kwd-group xml:lang="ru"><kwd>уравнения полимеров FENE</kwd><kwd>производная Ли</kwd><kwd>инварианты тензора конформации</kwd><kwd>интегрирование уравнений</kwd></kwd-group><funding-group/></article-meta><fn-group/></front><body></body><back><ref-list><ref id="B1"><label>1.</label><mixed-citation>Блохин А.М., Ткачёв Д.Л. Неустойчивость по Ляпунову стационарных течений полимерной жидкости в канале с перфорированными стенками// Мат. сб.- 2022.- 213, № 3.- С. 3-20.-DOI: 10.4213/sm9507.</mixed-citation></ref><ref id="B2"><label>2.</label><mixed-citation>Гантмахер Ф.Р. Теория матриц.- М.: Наука, 1986.</mixed-citation></ref><ref id="B3"><label>3.</label><mixed-citation>Ландау Л.Д., Лифшиц Е.М. 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