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Properties of regularized equations for barotropic gas mixtures
Journal of Mathematical Sciences. 2023. Vol. 270. No. 6. P. 815–826.
We consider regularizations of systems of equations for a multicomponent gas mixture dynamics in the barotropic multi-velocity and one-velocity cases. Energy balance equations are derived for them.
For the system of equations in the one-velocity case, the system linearized on a constant solution is studied, and, for the weak solutions to the initial-boundary value problem with zero boundary data, the existence and uniqueness are stated together with $L^2$-dissipativity.
Keywords: газовая динамикауравнение баланса энтропиибаротропная квазигазодинамическая система уравненийbarotropic quasi-gas dynamics system of equationsсуществование и единственность решенияPetrovskii parabolicityпараболичность по ПетровскомуL^2-dissipativity L^2-диссипативностьmulticomponent gas dynamics equationsexistence and uniqueness of solutionsentropy balance equation
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It is known that for every continuous real-valued
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А. А. Злотник, Т. А. Ломоносов, Доклады Российской академии наук. Математика, информатика, процессы управления (ранее - Доклады Академии Наук. Математика) 2023 Т. 514 № 1 С. 26–33
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Zlotnik A., Lomonosov T., Журнал вычислительной математики и математической физики 2022 Т. 62 № 12 С. 1981–2001
Изучается явная двухслойная симметричная по пространству схема на разнесенных сетках с квазигидродинамической регуляризацией для 1D баротропных систем уравнений движения газа.
Выводятся как необходимые условия, так и близкие к ним достаточные условия L²-диссипативности решений задачи Коши для ее линеаризации на постоянном решении при произвольном фоновом числе Маха M.
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