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## Корреляции флуктуаций течения, возбуждаемых случайной силой на фоне сдвигового потока

Журнал экспериментальной и теоретической физики. 2024. Т. 165. № 1. С. 128-140.

We examine fluctuations of vorticity excited by an external random force in two-dimensional fluid in the presence of a strong external shear flow. The problem is motivated by the analysis of big coherent vortices appearing as a consequence of the inverse energy cascade in a finite box at large Reynolds numbers. We develop the perturbation theory for calculating nonlinear corrections to correlation functions of the flow fluctuations assuming that the external force is short correlated in time. We analyze corrections to the pair correlation function of vorticity and some moments. The analysis enables one to establish validity of the perturbation theory for laboratory experiments and numerical simulations.

Ivchenko N., Vergeles S. S., Журнал экспериментальной и теоретической физики 2023 Т. 163 № 5 С. 724-733

We study statistical properties of the passive scalar advection in a 2D flow that consist of a steady-state shear flow and a relatively weak smooth random component taking into account the effects of finite weak diffusion. The model is closely related to the dynamics of passive scalar transfer inside coherent vortices emerging as a result ...

Added: February 15, 2024

Pavlov D., Galigerov V., Kolotinskii D. et al., International Journal of High Performance Computing Applications 2024 Vol. 38 No. 1 P. 34-49

Fluid dynamics is a ubiquitous problem that arises in different branches of science and industry. It is usually tackled by numerically solving differential equations on a finite grid. Molecular dynamics was not a feasible tool to approach fluid dynamics until very recently due to its disproportional computational complexity. In this paper we propose a new ...

Added: July 18, 2023

Leuven : KU Leuven Methusalem Group, 2015

Added: March 22, 2016

Zybin K., Il'yn A. S., Physics-Uspekhi 2016 Vol. 59 No. 12 P. 1241-1244

This paper reviews the statistical properties and calculates the velocity structure functions of flows produced by a large-scale random scaling force in the Burgers model. ...

Added: September 22, 2017

Arutyunov K., Lehtinen J. S., Superconductor Science and Technology 2013 Vol. 26 No. 3 P. 039503-039503

On the second page, after equation (1), the statement
‘. . . where RN is the normal state resistance, RQ D h=2e D
6:45 k is the superconducting quantum resistance, . . . ’
contains a misprint. The correct expression is RQ D h=.2e/2 D
6:45 k. ...

Added: March 24, 2014

Попель С.И., Морозова Т. И., Физика плазмы 2017 Т. 43 № 5 С. 474-484

The wave processes that take place under the interaction of the Earth’s magnetosphere with dusty plasma near the lunar surface are considered. It is shown that the waves can be excited for the photoelectron parameters corresponding to the quantum yield of the lunar regolith reported by Willis et al. [Photon and Particle Interactions with Surfaces ...

Added: January 12, 2018

П.А. Беспалов, О.Н. Савина, Письма в Астрономический журнал 2015 Т. 41 № 10 С. 651-656

The connection of between the formation and properties of areas characterized by the sharp gradient of electron temperature, with electrostatic turbulence, providing high a high effective electrons collision frequency and a low thermal conductivity of medium, is discussed. Simple dependences for the thermal conductivity, effective collision frequency and noise electric fields are obtained. For ...

Added: June 4, 2015

Kolokolov I., Turitsyn K., Journal of Experimental and Theoretical Physics 2002 Vol. 94 No. 6 P. 1193-1200

For the field u(x, t) governed by the Burgers equation with a thermal noise, short-time asymptotics
of multipoint correlators are obtained. Their exponential parts are independent of the correlator number. This
means that they are determined by a single rare fluctuation and exhibit the intermittency phenomenon ...

Added: February 25, 2017

Parfenyev V., Physical Review E - Statistical, Nonlinear, and Soft Matter Physics 2022 Vol. 106 No. 2 Article 025102

It is well known that an inverse turbulent cascade in a finite ($2 \pi \times 2 \pi$) two-dimensional periodic domain leads to the emergence of a system-sized coherent vortex dipole. We report a numerical hyperviscous study of the spatial vorticity profile inside one of the vortices. The exciting force was shortly correlated in time, random ...

Added: August 10, 2022

Bespalov P. A., O.N. Savina, Astronomy Letters 2015 Vol. 41 No. 10 P. 601-605

We discuss the connection of the formation and properties of solar atmosphere transition region
characterized by a steep electron temperature gradient with electrostatic turbulence, which provides a high
effective electron collision frequency and a low thermal conductivity of the medium. A simple dependence
of the noise electric field in the transition region on the effective collision frequency has ...

Added: September 30, 2015

Arutyunov K., Sajavaara T., Lehtinen J. S. et al., Physical Review B: Condensed Matter and Materials Physics 2012 Vol. 85 No. 9 P. 0945081-0945087

Electron transport properties of titanium nanowires were experimentally studied. Below the effective diameter
50nm all samples demonstrated a pronounced broadening of the R(T ) dependencies, which cannot be accounted
for by thermal fluctuations. Extensive microscopic and elemental analyses indicate the absence of structural or/and
geometrical imperfections capable of broadening the R(T ) transition to such an extent. We ...

Added: March 24, 2014

Vladimirova N., Shavit M., Belan S. et al., Physical Review E - Statistical, Nonlinear, and Soft Matter Physics 2021 Vol. 104 No. 1 Article 014129

When two resonantly interacting modes are in contact with a thermostat, their statistics is exactly Gaussian and the modes are statistically independent despite strong interaction. Considering a noise-driven system, we show that when one mode is pumped and another dissipates, the statistics of such cascades is never close to Gaussian, no matter what is the ...

Added: September 22, 2021

Arutyunov, K.Y., Astafiev O. V., Ioffe L. B. et al., Nature 2012 Vol. 484 No. 7394 P. 355-358

A hundred years after the discovery of superconductivity, one
fundamental prediction of the theory, coherent quantum phase
slip (CQPS), has not been observed. CQPS is a phenomenon exactly
dual1 to the Josephson effect; whereas the latter is a coherent
transfer of charges between superconducting leads2,3, the former
is a coherent transfer of vortices or fluxes across a superconducting
wire. In contrast ...

Added: March 24, 2014

Konstantin Yu. Arutyunov, Hongisto T. T., Lehtinen J. S. et al., Scientific Reports 2012 Vol. 2 No. 293 P. 1-7

The smaller the system, typically - the higher is the impact of fluctuations. In narrow superconducting wires
sufficiently close to the critical temperature Tc thermal fluctuations are responsible for the experimentally
observable finite resistance. Quite recently it became possible to fabricate sub-10 nm superconducting
structures, where the finite resistivity was reported within the whole range of experimentally obtainable
temperatures. ...

Added: March 24, 2014

Parfenyev V., Mogilevskiy E., Falkovich G., Physical Review E - Statistical, Nonlinear, and Soft Matter Physics 2023 Vol. 107 No. 5 Article 054114

We suggest a new computer-assisted approach to the development of turbulence theory. It allows one to impose lower and upper bounds on correlation functions using sum-of-squares polynomials. We demonstrate it on the minimal cascade model of two resonantly interacting modes when one is pumped and the other dissipates. We show how to present correlation functions ...

Added: May 16, 2023

Parfenyev V., Vointsev I., Skoba A. et al., Physics of Fluids 2021 Vol. 33 No. 6 P. 1-11

Strong rotation makes an underlying turbulent flow quasi-two-dimensional that leads to the upscale energy transfer. Recent numerical simulations show that under certain conditions, the energy is accumulated at the largest scales of the system, forming coherent vortex structures known as condensates. We analytically describe the interaction of a strong condensate with weak small-scale turbulent pulsations ...

Added: June 15, 2021

E. S. Pikina, Muratov A. R., Kats E. I. et al., Annals of Physics, Elsevier 2022 Vol. 447 Article 168916

The aim of this work is to revisit the phenomenological theory of the interaction between membrane inclusions, mediated by the membrane fluctuations. We consider the case where the inclusions are separated by distances larger than their characteristic size. Within our macroscopic approach a physical nature of such inclusions is not essential, however
we have always in ...

Added: October 28, 2022

Zybin K., Sirota V. A., Physical Review E - Statistical, Nonlinear, and Soft Matter Physics 2013 Vol. 88 No. 4

The appearance of vortex filaments, the power-law dependence of velocity and vorticity correlations and their multiscaling behavior are derived from the Navier-Stokes equation. This is possible due to interpretation of the Navier-Stokes equation as an equation with multiplicative noise and remarkable properties of random matrix products. ...

Added: October 20, 2014

Pelinovsky E., E.G. Shurgalina, Sergeeva A. et al., Physical Letters A 2013 Vol. 377 No. 1 P. 272-275

Two-soliton interactions play a definitive role in the formation of the structure of soliton turbulence in integrable systems. To quantify the contribution of these interactions to the dynamical and statistical characteristics of the nonlinear wave field of soliton turbulence we study properties of the spatial moments of the two-soliton solution of the Korteweg–de Vries (KdV) ...

Added: January 18, 2013

Zybin K., Sirota V. A., Physical Review E - Statistical, Nonlinear, and Soft Matter Physics 2012 Vol. 85 No. 5

We develop a theory of turbulence based on the inviscid Navier-Stokes equation. We get a simple but exact stochastic solution (vortex filament model) which allows us to obtain a power law for velocity structure functions in the inertial range. Combining the model with the multifractal conjecture, we calculate the scaling exponents without using the extended ...

Added: October 20, 2014

Kolokolov I., Kostenko M., Physical Review E - Statistical, Nonlinear, and Soft Matter Physics 2020 Vol. 101 No. 033108 P. 1-3

We consider two-dimensional turbulence in the presence of a condensate. The nondiagonal correlation
functions of the Lagrangian accelerations are calculated, and it is shown that they have the same universality
properties as the nondiagonal correlation functions of the velocity fluctuations. ...

Added: March 25, 2020

Parfenyev V., Vergeles S. S., Physics of Fluids 2021 Vol. 33 No. 11 Article 115128

In the presence of strong background rotation, the velocity field tends to become quasi-two-dimensional, which leads to the inverse energy cascade. If the damping is small enough, then the energy is accumulated at the largest scales of the system, forming coherent columnar vortex structures known as condensates. Recently, it was found that the radial velocity ...

Added: November 19, 2021

I.V.Kolokolov, V.V.Lebedev, Journal of Fluid Mechanics 2016 Vol. 809 No. paper R2 P. 1-11

We analyze velocity fluctuations inside coherent vortices generated as a result of the inverse cascade in the two-dimensional ($2d$) turbulence in a finite box. As we demonstrated in \citep{16KL}, the universal velocity profile, established in \citep{14LBFKL}, corresponds to the passive regime of the flow fluctuations. The property enables one to calculate correlation functions of the ...

Added: October 23, 2016

49606783, Mathematical notes 2017 Vol. 102 No. 2 P. 234-251

It is shown in the paper that the number pN(M) of partitions of a positive integer M
into N positive integer summands coincides with the Bose and Fermi distributions with logarithmic
accuracy if one identifies M with energy and N with the number of particles. We use the Gentile
statistics (a.k.a. parastatistics) to derive self-consistent algebraic equations that ...

Added: October 29, 2018