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Related papers: Origin of the Temperature Oscillation in Turbulent…

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The paper is devoted to the study of natural convection and the formation of delamination in an incompressible liquid due to convective laminar flows in a closed region heated from the side. Weak, medium and intensive modes of stationary…

Fluid Dynamics · Physics 2024-02-13 Alexey Fedyushkin

Even in the absence of externally applied temperature gradients, spontaneously generated temperature fluctuations arise in turbulent flows. We experimentally study these fluctuations in a closed von Karman swirling flow of air at Mach…

Fluid Dynamics · Physics 2023-01-31 Gaurav Prabhudesai , Stephane Perrard , Francois Petrelis , Stephan Fauve

In a range of physical systems, the first instability in Rayleigh-Bernard convection between nearly thermally insulating horizontal plates is large scale. This holds for thermal convection of fluids saturating porous media. Large-scale…

Fluid Dynamics · Physics 2008-08-20 Denis S. Goldobin , Elizaveta V. Shklyaeva

We perform direct numerical simulations of three dimensional Rayleigh-Taylor turbulence with a nonuniform singular initial temperature background. In such conditions, the mixing layer evolves under the driving of a varying effective Atwood…

Fluid Dynamics · Physics 2018-09-19 Luca Biferale , Guido Boffetta , Alexei A. Mailybaev , Andrea Scagliarini

Coherent large-scale circulations of turbulent thermal convection in air have been studied experimentally in a rectangular box heated from below and cooled from above using Particle Image Velocimetry. The hysteresis phenomenon in turbulent…

Fluid Dynamics · Physics 2009-11-11 A. Eidelman , T. Elperin , N. Kleeorin , A. Markovich , I. Rogachevskii

We studied flow organization and heat transfer properties in mixed turbulent convection within Poiseuille-Rayleigh-B\'enard channels subjected to temporally modulated sinusoidal wall temperatures. Three-dimensional direct numerical…

Fluid Dynamics · Physics 2025-03-12 Ao Xu , Rui-Qi Li , Heng-Dong Xi

The spectra of turbulent heat flux $\mathrm{H}(k)$ in Rayleigh-B\'{e}nard convection with and without uniform rotation are presented. The spectrum $\mathrm{H}(k)$ scales with wave number $k$ as $\sim k^{-2}$. The scaling exponent is almost…

Fluid Dynamics · Physics 2016-05-23 Hirdesh K. Pharasi , Deepesh Kumar , Krishna Kumar , Jayanta K. Bhattacharjee

Natural convection is ubiquitous throughout the physical sciences and engineering, yet many of its important properties remain elusive. To study convection in a novel context, we derive and solve a quasilinear form of the Rayleigh-B\'enard…

Fluid Dynamics · Physics 2024-02-29 Liam O'Connor , Daniel Lecoanet , Evan H. Anders

We studied experimentally the effect of turbulent thermal diffusion in a multi-fan turbulence generator which produces a nearly homogeneous and isotropic flow with a small mean velocity. Using Particle Image Velocimetry and Image Processing…

Fluid Dynamics · Physics 2009-11-11 A. Eidelman , T. Elperin , N. Kleeorin , I. Rogachevskii , I. Sapir-Katiraie

Two-dimensional direct numerical simulations are conducted for convection sustained by uniform internal heating in a horizontal fluid layer. Top and bottom boundary temperatures are fixed and equal. Prandtl numbers range from 0.01 to 100,…

Fluid Dynamics · Physics 2015-03-13 David Goluskin , Edward A. Spiegel

Asymptotically large Reynolds number hydrodynamic turbulence is characterized by multi-scaling of moments of velocity increments and spatial derivatives. With decreasing Reynolds number toward $R_{\lambda}=R^{tr}_{\lambda}\approx 9.0$, the…

Fluid Dynamics · Physics 2020-06-22 Victor Yakhot

The onset of convection in the form of magneto-inertial waves in a rotating fluid sphere permeated by a constant axial electric current is studied through a perturbation analysis. Explicit expressions for the dependence of the Rayleigh…

Fluid Dynamics · Physics 2021-01-19 Radostin D. Simitev , Friedrich H. Busse

We describe a novel phenomenon in which vortices are produced due to resonant oscillations of a scalar field which is driven by a periodically varying temperature T, with T remaining much below the critical temperature $T_c$. Also, in a…

High Energy Physics - Phenomenology · Physics 2009-10-31 Sanatan Digal , Rajarshi Ray , Supratim Sengupta , Ajit M. Srivastava

Mesoscale convection covers an intermediate scale range between small-scale turbulence and the global organization of the convection flow. It is often characterized by an order of the convection patterns despite very high Rayleigh numbers…

In this work, experimental and numerical investigations are considered for confined buoyant turbulent jet with varying inlet temperatures. Results of the experimental work and numerical simulations for the problem under consideration are…

Fluid Dynamics · Physics 2013-03-01 M. F. El-Amin , A. Salama , S. Sun

We use direct numerical simulations to investigate the interaction between the temperature field of a fluid and the temperature of small particles suspended in the flow, employing both one and two-way thermal coupling, in a statistically…

Fluid Dynamics · Physics 2020-01-08 Maurizio Carbone , Andrew D. Bragg , Michele Iovieno

The possible transition to the so-called ultimate regime, wherein both the bulk and the boundary layers are turbulent, has been an outstanding issue in thermal convection, since the seminal work by Kraichnan [Phys. Fluids 5, 1374 (1962)].…

We investigate the stability and dynamics of natural convection in two dimensions, subject to inhomogeneous boundary conditions. In particular, we consider a Rayleigh-B\`enard (RB) cell, where the horizontal top boundary contains a periodic…

Fluid Dynamics · Physics 2014-03-14 P. Ripesi , L. Biferale , M. Sbragaglia , A. Wirth

We study the dynamical regimes of a density-stratified fluid confined between isothermal no-slip top and bottom boundaries (at temperatures $T_t$ and $T_b$) via direct numerical simulation. The thermal expansion coefficient of the fluid is…

Fluid Dynamics · Physics 2017-09-20 L. -A. Couston , D. Lecoanet , B. Favier , M. Le Bars

We present hydrodynamic equations of compressible fluids in gravity as a generalization of those in the Boussinesq approximation used for nearly incompressible fluids. They account for adiabatic processes taking place throughout the cell…

Soft Condensed Matter · Physics 2009-11-07 Akira Furukawa , Akira Onuki