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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">Journal of Samara State Technical University, Ser. Physical and Mathematical Sciences</journal-id><journal-title-group><journal-title xml:lang="en">Journal of Samara State Technical University, Ser. Physical and Mathematical Sciences</journal-title><trans-title-group xml:lang="ru"><trans-title>Вестник Самарского государственного технического университета. Серия «Физико-математические науки»</trans-title></trans-title-group></journal-title-group><issn publication-format="print">1991-8615</issn><issn publication-format="electronic">2310-7081</issn><publisher><publisher-name xml:lang="en">Samara State Technical University</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="publisher-id">633868</article-id><article-id pub-id-type="doi">10.14498/vsgtu2104</article-id><article-id pub-id-type="edn">JTFDKW</article-id><article-categories><subj-group subj-group-type="toc-heading" xml:lang="en"><subject>Differential Equations and Mathematical Physics</subject></subj-group><subj-group subj-group-type="toc-heading" xml:lang="ru"><subject>Дифференциальные уравнения и математическая физика</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">Hydrodynamics of an ideal incompressible fluid with a linear velocity field</article-title><trans-title-group xml:lang="ru"><trans-title>Гидродинамика идеальной несжимаемой жидкости с линейным полем скоростей</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0009-0003-5480-9366</contrib-id><contrib-id contrib-id-type="spin">9640-3992</contrib-id><name-alternatives><name xml:lang="en"><surname>Zagitov</surname><given-names>Ruslan R.</given-names></name><name xml:lang="ru"><surname>Загитов</surname><given-names>Руслан Ринатович</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>Research Engineer; Lab. of Differantial Equations of Mechanics</p></bio><bio xml:lang="ru"><p>инженер-исследователь; лаб. дифференциальных уравнений механики</p></bio><email>rr.zagitov.02@gmail.com</email><uri>https://www.mathnet.ru/person228241</uri><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-5127-4584</contrib-id><name-alternatives><name xml:lang="en"><surname>Yulmukhametova</surname><given-names>Yulia V.</given-names></name><name xml:lang="ru"><surname>Юлмухаметова</surname><given-names>Юлия Валерьевна</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>Cand. Phys. &amp; Math. Sci., Associate Professor; Researcher; Lab. of Differantial Equations of Mechanics</p></bio><bio xml:lang="ru"><p>кандидат физико-математических наук, доцент, научный сотрудник, лаб. дифференциальных уравнений механики</p></bio><email>yulmuhametova.yuv@ugatu.su</email><uri>https://www.mathnet.ru/person65962</uri><xref ref-type="aff" rid="aff1"/></contrib></contrib-group><aff-alternatives id="aff1"><aff><institution xml:lang="en">Mavlyutov Institute of Mechanics, Ufa Centre of the Russian Academy of Sciences</institution></aff><aff><institution xml:lang="ru">Институт механики им. Р. Р. Мавлютова — обособленное структурное подразделение УФИЦ РАН</institution></aff></aff-alternatives><pub-date date-type="pub" iso-8601-date="2025-05-20" publication-format="electronic"><day>20</day><month>05</month><year>2025</year></pub-date><volume>29</volume><issue>1</issue><issue-title xml:lang="en"/><issue-title xml:lang="ru"/><fpage>37</fpage><lpage>54</lpage><history><date date-type="received" iso-8601-date="2024-07-24"><day>24</day><month>07</month><year>2024</year></date><date date-type="accepted" iso-8601-date="2024-10-23"><day>23</day><month>10</month><year>2024</year></date></history><permissions><copyright-statement xml:lang="en">Copyright ©; 2025, Authors; Samara State Technical University (Compilation, Design, and Layout)</copyright-statement><copyright-statement xml:lang="ru">Copyright ©; 2025, Авторский коллектив; Самарский государственный технический университет (составление, дизайн, макет)</copyright-statement><copyright-year>2025</copyright-year><copyright-holder xml:lang="en">Authors; Samara State Technical University (Compilation, Design, and Layout)</copyright-holder><copyright-holder xml:lang="ru">Авторский коллектив; Самарский государственный технический университет (составление, дизайн, макет)</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/4.0</ali:license_ref></license></permissions><self-uri xlink:href="https://journals.eco-vector.com/1991-8615/article/view/633868">https://journals.eco-vector.com/1991-8615/article/view/633868</self-uri><abstract xml:lang="en"><p>In this study, a three-dimensional gas-dynamic model of an ideal incompressible fluid is proposed, where the solution is sought in the form of a linear velocity field with inhomogeneous deformation. The problem is formulated in both Eulerian and Lagrangian variables. Exact solutions are obtained for a special linearity matrix, generalizing previously known solutions. The equations of world lines for these solutions are derived, the trajectories of fluid particle motion are constructed, and the evolution of the initial spherical particle volume is investigated. The equations of constant pressure surfaces are presented and their time dynamics is analyzed. Special attention is paid to the analysis of particle motion in an ideal incompressible fluid and to obtaining new, more general solutions.</p></abstract><trans-abstract xml:lang="ru"><p>Предложена трехмерная газодинамическая модель идеальной несжимаемой жидкости, в которой решение ищется в виде линейного поля скоростей с неоднородной деформацией. Постановка задачи дана как в эйлеровых, так и в лагранжевых переменных. Найдены точные решения для специальной матрицы линейности, обобщающие известные ранее решения. Получены уравнения мировых линий для этих решений, построены траектории движения частиц жидкости и исследована эволюция начального сферического объема частиц. Приведены уравнения поверхностей постоянного давления и проанализирована их динамика во времени. Основное внимание уделено анализу движения частиц идеальной несжимаемой жидкости и получению новых, более общих решений.</p></trans-abstract><kwd-group xml:lang="en"><kwd>linear velocity field</kwd><kwd>gas dynamics</kwd><kwd>incompressible fluid</kwd><kwd>inhomogeneous deformation</kwd><kwd>world lines</kwd><kwd>trajectory</kwd></kwd-group><kwd-group xml:lang="ru"><kwd>линейное поле скоростей</kwd><kwd>газовая динамика</kwd><kwd>несжимаемая жидкость</kwd><kwd>неоднородная деформация</kwd><kwd>мировые линии</kwd><kwd>траектория</kwd></kwd-group><funding-group><funding-statement xml:lang="en">This research was supported by the Ministry of Science and Higher Education of the Russian Federation (state assignment no. 124030400064-2; FMRS-2024-0001)</funding-statement><funding-statement xml:lang="ru">Исследование выполнено при финансовой поддержке Министерства науки и высшего образования Российской Федерации в рамках государственного задания (номер проекта: 124030400064-2; FMRS-2024-0001)</funding-statement></funding-group></article-meta></front><body></body><back><ref-list><ref id="B1"><label>1.</label><citation-alternatives><mixed-citation xml:lang="en">Chandrasekhar S. 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