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Related papers: Generalized Knudsen Number for Unsteady Fluid Flow

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Through a discussion of some typical unsteady hydrodynamic flows, we argue that the time averaged hydrodynamic functions at each point give a rather sparse filling of the local jet space. This situation then suggests a set of time dependent…

Fluid Dynamics · Physics 2014-07-08 Clifford Chafin

In fairly general conditions we give explicit (smooth) solutions for the potential flow. We show that, rigorously speaking, the equations of the fluid mechanics have not rotational solutions. However, within the usual approximations of an…

Fluid Dynamics · Physics 2023-09-21 Marian Apostol

We consider transition to strong turbulence in an infinite fluid stirred by a gaussian random force. The transition is {\bf defined} as a first appearance of anomalous scaling of normalized moments of velocity derivatives (dissipation…

Fluid Dynamics · Physics 2017-08-02 Victor Yakhot , Diego Donzis

We study a model of fully developed turbulence of a compressible fluid, based on the stochastic Navier-Stokes equation, by means of the field theoretic renormalization group. In this approach, scaling properties are related to the fixed…

Statistical Mechanics · Physics 2017-04-21 N. V. Antonov , N. M. Gulitskiy , M. M. Kostenko , T. Lučivjanský

We study the two-dimensional incompressible Navier-Stokes equations in a channel $\Omega=(0,L)\times(0,H)$ with small viscosity $\varepsilon\ll1$, an $\varepsilon$-Navier slip condition on the horizontal walls, and a viscous inflow…

Analysis of PDEs · Mathematics 2026-02-24 Yan Guo , Zhuolun Yang

Fully-developed incompressible Navier-Stokes turbulence in three dimensions is a dissipative dynamical system that exhibits strong departure from absolute equilibrium. Nevertheless, several kinds of representation by Tsallis equilibria have…

Chaotic Dynamics · Physics 2009-11-10 Toshiyuki Gotoh , Robert H. Kraichnan

We establish pointwise decay estimates for the velocity field of a steady two-dimensional Stokes flow around a rotating body via a new approach rather than analysis adopted in the previous literature. The novelty is to analyze the singular…

Analysis of PDEs · Mathematics 2021-12-15 Toshiaki Hishida , Mads Kyed

In this article we consider the linear stability of the two-dimensional flow induced by the linear stretching of a surface in the streamwise direction. The basic flow is a rare example of an exact analytical solution of the Navier-Stokes…

Fluid Dynamics · Physics 2021-08-10 P. T. Griffiths , S. O. Stephen , M. Khan

By analogy with the kinetic theory of gases, most turbulence modeling strate- gies rely on an eddy viscosity to model the unresolved turbulent fluctuations. How- ever, the ratio of unresolved to resolved scales - very much like a degree of…

Fluid Dynamics · Physics 2016-08-24 Marcello Righi

Based on the recently-established Master kinetic equation and related Master constant H-theorem which describe the statistical behavior of the Boltzmann-Sinai classical dynamical system for smooth and hard spherical particles, the problem…

Fluid Dynamics · Physics 2016-11-01 Massimo Tessarotto , Michael Mond , Claudio Asci

The Navier--Stokes equations for incompressible flows past a two--dimensional sphere are considered in this article. The existence of an inertial form of the equations is established. Furthermore for the first time for fluid equations, we…

chao-dyn · Physics 2008-02-03 Roger Temam , Shouhong Wang

We propose a novel approach to induce anomalous dissipation through advection driven by turbulent fluid flows. Specifically, we establish the existence of a velocity field $v$ satisfying randomly forced Navier-Stokes equations, leading to…

Analysis of PDEs · Mathematics 2024-02-14 Martina Hofmanová , Umberto Pappalettera , Rongchan Zhu , Xiangchan Zhu

We consider the large time behavior of the three-dimensional Navier-Stokes flow around a rotating rigid body. Assume that the angular velocity of the body gradually increases until it reaches a small terminal one at a certain finite time…

Analysis of PDEs · Mathematics 2020-10-06 T. Takahashi

Attention has been paid to the similarity and duality between the Gregory-Laflamme instability of black strings and the Rayleigh-Plateau instability of extended fluids. In this paper, we derive a set of simple (1+1)-dimensional equations…

High Energy Physics - Theory · Physics 2011-05-18 Umpei Miyamoto

A freely falling stream of weakly cohesive granular particles is modeled and analysed with help of event driven simulations and continuum hydrodynamics. The former show a breakup of the stream into droplets, whose size is measured as a…

Soft Condensed Matter · Physics 2015-06-04 Stephan Ulrich , Annette Zippelius

We study the Navier-Stokes equations governing the motion of isentropic compressible fluid in three dimensions driven by a multiplicative stochastic forcing. In particular, we consider a stochastic perturbation of the system as a function…

Analysis of PDEs · Mathematics 2017-01-03 Dominic Breit , Martina Hofmanová

The flow of a viscous fluid is perturbed by its internal friction which generates heat and leads to a small temperature change. This does not occur for an ideal fluid. We would like to resolve this picture as a function of the dynamical…

Fluid Dynamics · Physics 2014-09-30 Billy D. Jones

In this note, which is of general stability theory interest, we discuss some of the key assertions usually stated in the context of the transition to turbulence problem. In particular, the two main points made here in the setting of the…

Fluid Dynamics · Physics 2008-07-01 R. Krechetnikov , J. E. Marsden

The problem of wave disturbance propagation in rarefied gas in gravity field is explored. The system of hydrodynamic-type equations for a stratified gas in gravity field is derived from BGK equation by method of piecewise continuous…

Fluid Dynamics · Physics 2009-11-10 D. A. Vereshchagin , S. B. Leble , M. A. Solovchuk

A combination of molecular-dynamics simulations, theoretical predictions, and previous experiments are used in a two-part study to determine the role of the Knudsen layer in rapid granular flows. First, a robust criterion for the…

Soft Condensed Matter · Physics 2009-11-13 J. E. Galvin , C. M. Hrenya , R. D. Wildman