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Double-deck structure of the boundary layer in the problem of flow in an axially symmetric pipe with small irregularities on the wall for large Reynolds numbers
Russian Journal of Mathematical Physics. 2017. Vol. 24. No. 1. P. 1-18.
The problem of flow of a viscous incompressible fluid in an axially symmetric pipe with small irregularities on the wall is considered. An asymptotic solution of the problem with the double-deck structure of the boundary layer and the unperturbed flow in the environment (the “core flow”) is obtained. The results of flow numerical simulation in the thin and “thick” boundary layers are given.
Danilov V., Gaydukov R., Mathematical notes 2015 Vol. 98 No. 4 P. 561-571
We consider the problem of a viscous incompressible fluid flow along a flat plate with a small solitary perturbation (of hump, step, or corner type) for large Reynolds numbers. We obtain an asymptotic solution in which the boundary layer has a double-deck structure. ...
Added: September 27, 2015
Gaydukov R. K., European Journal of Mechanics - B/Fluids 2017 Vol. 66 P. 102-108
We consider the problem of a viscous compressible subsonic fluid flow along a flat plate with small periodic irregularities on the surface for large Reynolds numbers. We obtain a formal asymptotic solution with double-deck structure of the boundary layer. We present the results of numerical simulation of flow in the thin boundary layer (i.e., in ...
Added: July 9, 2017
Gaydukov R., Danilov V., Наноструктуры. Математическая физика и моделирование 2016 Т. 15 № 1 С. 5-102
We study the existence conditions for a double-deck structure of a boundary layer in typical problems of incompressible fluid flow along surfaces with small irregularities (periodic or localized) for large Reynolds number. We obtain characteristic scales (a power of a small parameter included in a solution) which lead to the double-deck structure, and we obtain ...
Added: September 27, 2016
Gaydukov R. K., Fonareva A. V., Russian Journal of Mathematical Physics 2019 Vol. 26 No. 3 P. 334-343
The problem of viscous compressible fluid flow in an axially symmetric pipe with small periodic irregularities on the wall is considered for large Reynolds numbers. An asymptotic solution with double-deck structure of the boundary layer and unperturbed core flow is obtained. Numerical investigations of the influence of the density of the core flow on the flow behavior in ...
Added: September 2, 2019
Danilov V., Gaydukov R., Russian Journal of Mathematical Physics 2015 Vol. 22 No. 2 P. 161-173
A fluid flow along a plate with small irregularities on the surface is considered for large Reynolds numbers. The boundary layer has a double-deck structure, i.e., both a thin boundary layer and the classical Prandtl boundary layer are present. It is proved that the solution of the boundary-value problem thus obtained exists and is unique ...
Added: September 3, 2015
Gaydukov R. K., Borisov D. I., Mathematical notes 2016 Vol. 99 No. 5 P. 636-642
A fluid flow along a semi-infinite plate with small periodic irregularities on the surface is considered for large Reynolds numbers. The boundary layer has a double-deck structure: a thin boundary layer (“lower deck”) and a classical Prandtl boundary layer (“upper deck”). The aim of this paper is to prove the existence and uniqueness of the ...
Added: May 18, 2016
Gaydukov R., Сибирский журнал вычислительной математики 2022 Т. 15 № 2 С. 97-109
A viscous liquid flow along a semi-infinite plate with small periodic irregularities on the surface was
considered for large Reynolds numbers. The flow near the plate is described by Prandtl equations with
induced pressure which are non-classical PDE, because they contain a limiting term. The main goal is to
construct a numerical algorithm for solving these equations with ...
Added: June 10, 2020
V. G. Danilov, R. K. Gaydukov, Russian Journal of Mathematical Physics 2022 Vol. 29 No. 4 P. 431-455
A problem of a nonstationary incompressible viscous fluid ow along a plate with small fast-oscillating irregularities on the surface for a large Reynolds number is considered by using rigorous methods of mathematical physics. Depending on the scales of irregularities in the problem under study, there arises a solution that describes the double-deck or triple-deck structure boundary layers on ...
Added: August 19, 2020
Gaydukov R., European Journal of Mechanics - B/Fluids 2018 Vol. 71 P. 59-65
We consider the problem of flow of a viscous compressible subsonic fluid along a flat plate with small localized (hump-type) irregularities on the surface for large Reynolds numbers. We obtain a formal asymptotic solution with double-deck structure of the boundary layer. We present the results of numerical simulation of the flow in the thin boundary ...
Added: November 20, 2017
Bekmaganbetov K., Chechkin G., Chepyzhov V. V. et al., Discrete and Continuous Dynamical Systems 2017 Vol. 37 No. 5 P. 2375-2393
We consider the 3D Navier--Stokes systems with randomly rapidly oscillating right--hand sides. Under the assumption that the random functions are ergodic and statistically homogeneous in space variables or in time variables we prove that the trajectory attractors of these systems tend to the trajectory attractors of homogenized 3D Navier--Stokes systems whose right--hand sides are the ...
Added: June 7, 2017
Demenko V. N., Исмагилов Р. С., Fedotov A., М. : МИЭМ НИУ ВШЭ, 2013
Методические указания к курсовой работе являются составной частью учебно-методического комплекса по математическому анализу. Рассмотрены теоретические основы элементарных асимптотических методов и приведены некоторые примеры их применения. ...
Added: October 18, 2013
Kashtanov V., Ivchenko G., Коваленко И. Н., М. : Либроком, 2012
В настоящем пособии в доступной для первоначального изучения форме излагаются элементы основных направлений теории массового обслуживания --- раздела теории вероятностей, изучающего системы, предназначенные для обслуживания массового потока требований случайного характера. Представлена общая характеристика систем массового обслуживания; выделены такие разделы теории, как асимптотические методы, приоритетные системы, статистика систем массового обслуживания и моделирование систем массового обслуживания.
Второе издание ...
Added: October 18, 2012
Ivashov E., Князева М. П., Костомаров П. С. et al., Международный журнал экспериментального образования 2014 Т. 2 № 1 С. 105-108
The problem of small sample size, i.e. absence of required quantity of empirical data for decision making of rational constructive-technically, in case of computer-aided design of elements, nodes and technical objects’ devices is considered. Randomization approach for blur factor’s determination of nonparametric decision rules is suggested. The approach of Laplace’s method in using cores’ asymptotic ...
Added: January 25, 2014
М. : Физический факультет МГУ им. М.В. Ломоносова, 2014
Сборник тезисов докладов Международного научного семинара Актуальные проблемы математической физики. МГу им. М.В. Ломоносова, 28-29 ноября 2014 г. ...
Added: November 28, 2014
Grushin V. V., Dobrokhotov S. Y., Математические заметки 2014 Т. 95 № 3 С. 359-375
The system of equations of gravity surface waves is considered in the case where the basin's bottom is given by a rapidly oscillating function against a background of slow variations of the bottom. Under the assumption that the lengths of the waves under study are greater than the characteristic length of the basin bottom's oscillations ...
Added: May 21, 2014
Gaidukov R.K., Danilov V.G., , in : Abstracts: Russian-French Workshop “Mathematical Hydrodynamics”, August 22–27, 2016. : Novosibirsk : [б.и.], 2016. P. 20-22.
We consider a non-stationary problem of an incompressible viscous fluid flow along surfaces with small irregularities for large Reynolds number, which have a formal asymptotic solution with a double-deck structure of the boundary layer. ...
Added: September 28, 2016
Gaydukov R., Сибирские электронные математические известия 2024 Т. 21 № 1 С. 178-187
In this paper we study a Rayleigh-type equation on a semi-infinite cylinder with a Coulomb-type potential.
This equation arises in the double-deck boundary layer structure in the problem of flow induced by a uniformly rotating disk with small periodic irregularities on its surface for large Reynolds numbers. Using combined numerical and analytical approach, the existence of ...
Added: February 17, 2024
Fonareva A. V., Gaydukov R. K., Russian Journal of Mathematical Physics 2021 Vol. 28 No. 2 P. 224-243
A subsonic flow of a viscous compressible fluid in a two-dimensional channel with small periodic or localized irregularities on the walls for large Reynolds numbers is considered. A formal asymptotic solution with double-deck structure of the boundary layer is constructed. A nontrivial time hierarchy is discovered in the decks. An analysis of the scales of irregularities at ...
Added: March 22, 2021
Zlotnik A., Математическое моделирование 2012 Т. 24 № 4 С. 65-79
Дан краткий подход к построению баротропной квазигазодинамической (КГД) системы уравнений с помощью специальной регуляризации по времени баротропной системы уравнений Навье-Стокса вязкого сжимаемого газа. Этот подход обобщен на случай КГД системы с общими уравнениями состояния газа, массовой силой и источником тепла. Для баротропной КГД системы с потенциальной массовой силой выведено поточечное уравнение энергетического баланса. В качестве ...
Added: June 30, 2012
Gaydukov R., European Journal of Mechanics - B/Fluids 2021 Vol. 89 P. 401-410
An asymptotic solution with double-deck boundary layer structure is constructed for the problem of an incompressible fluid flow along a semi-infinite plate with small localized or periodic (fast-oscillating) irregularities on the surface whose shape depends on time. Numerical simulation of flow in the near-plate region is presented for two types of the shape change: oscillations of the ...
Added: January 4, 2021
Gaydukov R., Fonareva A. V., European Journal of Mechanics - B/Fluids 2022 Vol. 94 P. 50-59
The problem of a rotating disk with slightly perturbed surface immersed in a viscous fluid is considered.
The asymptotic solutions with double-deck structure of the boundary layer are constructed for symmetric
periodic and localized types of irregularities on the disk surface for large Reynolds numbers. The paper
presents the results of numerical simulations of the flow near the ...
Added: November 14, 2021
Kotelnikova M. V., Aistov A., Вестник Нижегородского университета им. Н.И. Лобачевского. Серия: Социальные науки 2019 Т. 55 № 3 С. 183-189
The article describes a method that allows to improve the content of disciplines of the mathematical cycle by dividing them into invariant (general) and variable parts. The invariants were identified for such disciplines as «Linear algebra», «Mathematical analysis», «Probability theory and mathematical statistics» delivered to Bachelors program students of economics at several universities. Based on ...
Added: January 28, 2020
Borzykh D., ЛЕНАНД, 2021
Книга представляет собой экспресс-курс по теории вероятностей в контексте начального курса эконометрики. В курсе в максимально доступной форме изложен тот минимум, который необходим для осознанного изучения начального курса эконометрики. Данная книга может не только помочь ликвидировать пробелы в знаниях по теории вероятностей, но и позволить в первом приближении выучить предмет «с нуля». При этом, благодаря доступности изложения и небольшому объему книги, ...
Added: February 20, 2021
В. Л. Попов, Математические заметки 2017 Т. 102 № 1 С. 72-80
Мы доказываем, что аффинно-треугольные подгруппы являются борелевскими подгруппами групп Кремоны. ...
Added: May 3, 2017