1
|
Xia KQ, Huang SD, Xie YC, Zhang L. Tuning heat transport via coherent structure manipulation: recent advances in thermal turbulence. Natl Sci Rev 2023; 10:nwad012. [PMID: 37457662 PMCID: PMC10339376 DOI: 10.1093/nsr/nwad012] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 08/25/2022] [Accepted: 10/11/2022] [Indexed: 07/20/2023] Open
Abstract
Tuning transport properties through the manipulation of elementary structures has achieved great success in many areas, such as condensed matter physics. However, the ability to manipulate coherent structures in turbulent flows is much less explored. This article reviews a recently discovered mechanism of tuning turbulent heat transport via coherent structure manipulation. We first show how this mechanism can be realized by applying simple geometrical confinement to a classical thermally driven turbulence, which leads to the condensation of elementary coherent structures and significant heat-transport enhancement, despite the resultant slower flow. Some potential applications of this new paradigm in passive heat management are also discussed. We then explain how the heat transport behaviors in seemingly different turbulence systems can be understood by this unified framework of coherent structure manipulation. Several future directions in this research area are also outlined.
Collapse
Affiliation(s)
| | - Shi-Di Huang
- Center for Complex Flows and Soft Matter Research and Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Yi-Chao Xie
- State Key Laboratory for Strength and Vibration of Mechanical Structures and School of Aerospace, Xi’an Jiaotong University, Xi’an 710049, China
| | - Lu Zhang
- Center for Complex Flows and Soft Matter Research and Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| |
Collapse
|
2
|
Zheng JL, Liu YL. Experimental study on the flow structures and dynamics of turbulent Rayleigh-Bénard convection in an annular cell. Phys Rev E 2023; 107:065112. [PMID: 37464695 DOI: 10.1103/physreve.107.065112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2023] [Accepted: 06/04/2023] [Indexed: 07/20/2023]
Abstract
We conduct an experimental study on the flow structures and dynamics of turbulent Rayleigh-Bénard convection in an annular cell with radius ratio η≃0.5 and aspect ratio Γ≃4. The working fluid is water with a Prandtl number of Pr≃5.4, and the Rayleigh number (Ra) ranges from 5.05×10^{7} to 5.05×10^{8}. The multithermal-probe method and the particle image velocimetry technique are employed to measure the temperature profiles and the velocity fields, respectively. Two distinct states with multiroll standing waves are observed, which are the quadrupole state (QS) characterized by a four-roll structure and the sextupole state (SS) by a six-roll structure. The scaling exponents of Reynolds number Re with Ra are different for the two states, which are 0.56 for QS and 0.41 for SS. In addition, the standing waves become unstable upon tilting the cell by 1^{∘} in relation to the horizontal plane, and they evolve into traveling waves. At relatively high Ra, for instance, Ra⩾2.55×10^{8}, it is observed that the traveling wave state SS undergoes a transition to the traveling wave state QS. However, the opposite transition from QS to SS is not observed in our experiments. Our findings provide insights into the flow structures and dynamics in the convection flow with rotation symmetry.
Collapse
Affiliation(s)
- Ji-Li Zheng
- Shanghai Institute of Applied Mathematics and Mechanics, School of Mechanics and Engineering Science, Shanghai University, Shanghai 200072, China
| | - Yu-Lu Liu
- Shanghai Institute of Applied Mathematics and Mechanics, School of Mechanics and Engineering Science, Shanghai University, Shanghai 200072, China
- School of Science, Shanghai Institute of Technology, Shanghai 201418, China
| |
Collapse
|
3
|
Schindler F, Eckert S, Zürner T, Schumacher J, Vogt T. Collapse of Coherent Large Scale Flow in Strongly Turbulent Liquid Metal Convection. PHYSICAL REVIEW LETTERS 2022; 128:164501. [PMID: 35522515 DOI: 10.1103/physrevlett.128.164501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 10/28/2021] [Accepted: 01/20/2022] [Indexed: 06/14/2023]
Abstract
The large-scale flow structure and the turbulent transfer of heat and momentum are directly measured in highly turbulent liquid metal convection experiments for Rayleigh numbers varied between 4×10^{5} and ≤5×10^{9} and Prandtl numbers of 0.025≤Pr≤0.033. Our measurements are performed in two cylindrical samples of aspect ratios Γ=diameter/height=0.5 and 1 filled with the eutectic alloy GaInSn. The reconstruction of the three-dimensional flow pattern by 17 ultrasound Doppler velocimetry sensors detecting the velocity profiles along their beam lines in different planes reveals a clear breakdown of coherence of the large-scale circulation for Γ=0.5. As a consequence, the scaling laws for heat and momentum transfer inherit a dependence on the aspect ratio. We show that this breakdown of coherence is accompanied with a reduction of the Reynolds number Re. The scaling exponent β of the power law Nu∝Ra^{β} crosses eventually over from β=0.221 to 0.124 when the liquid metal flow at Γ=0.5 reaches Ra≳2×10^{8} and the coherent large-scale flow is completely collapsed.
Collapse
Affiliation(s)
- Felix Schindler
- Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
| | - Sven Eckert
- Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
| | - Till Zürner
- Technische Universität Ilmenau, 98684 Ilmenau, Germany
- UME, ENSTA Paris, Institut Polytechnique de Paris, 91120 Palaiseau, France
| | | | - Tobias Vogt
- Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
| |
Collapse
|
4
|
Iyer KP. Liquid-Metal Flows Show Surprising Heat Transport Behavior. PHYSICS 2022. [DOI: 10.1103/physics.15.57] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
5
|
Ahlers G, Bodenschatz E, Hartmann R, He X, Lohse D, Reiter P, Stevens RJAM, Verzicco R, Wedi M, Weiss S, Zhang X, Zwirner L, Shishkina O. Aspect Ratio Dependence of Heat Transfer in a Cylindrical Rayleigh-Bénard Cell. PHYSICAL REVIEW LETTERS 2022; 128:084501. [PMID: 35275677 DOI: 10.1103/physrevlett.128.084501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 01/13/2022] [Indexed: 06/14/2023]
Abstract
While the heat transfer and the flow dynamics in a cylindrical Rayleigh-Bénard (RB) cell are rather independent of the aspect ratio Γ (diameter/height) for large Γ, a small-Γ cell considerably stabilizes the flow and thus affects the heat transfer. Here, we first theoretically and numerically show that the critical Rayleigh number for the onset of convection at given Γ follows Ra_{c,Γ}∼Ra_{c,∞}(1+CΓ^{-2})^{2}, with C≲1.49 for Oberbeck-Boussinesq (OB) conditions. We then show that, in a broad aspect ratio range (1/32)≤Γ≤32, the rescaling Ra→Ra_{ℓ}≡Ra[Γ^{2}/(C+Γ^{2})]^{3/2} collapses various OB numerical and almost-OB experimental heat transport data Nu(Ra,Γ). Our findings predict the Γ dependence of the onset of the ultimate regime Ra_{u,Γ}∼[Γ^{2}/(C+Γ^{2})]^{-3/2} in the OB case. This prediction is consistent with almost-OB experimental results (which only exist for Γ=1, 1/2, and 1/3) for the transition in OB RB convection and explains why, in small-Γ cells, much larger Ra (namely, by a factor Γ^{-3}) must be achieved to observe the ultimate regime.
Collapse
Affiliation(s)
- Guenter Ahlers
- Max Planck Institute for Dynamics and Self-Organization, 37077 Göttingen, Germany
- Department of Physics, University of California, Santa Barbara, California 93106, USA
| | - Eberhard Bodenschatz
- Max Planck Institute for Dynamics and Self-Organization, 37077 Göttingen, Germany
- Max Planck-University of Twente Center for Complex Fluid Dynamics, 7500 AE Enschede, Netherlands
- Institute for the Dynamics of Complex Systems, Georg-August-University Göttingen, 37073 Göttingen, Germany
- Laboratory of Atomic and Solid-State Physics and Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, New York 14853, USA
| | - Robert Hartmann
- Physics of Fluids Group, J. M. Burgers Center for Fluid Dynamics and MESA+ Institute, University of Twente, 7500 AE Enschede, Netherlands
| | - Xiaozhou He
- Max Planck Institute for Dynamics and Self-Organization, 37077 Göttingen, Germany
- School of Mechanical Engineering and Automation, Harbin Institute of Technology, Shenzhen, 518055 China
| | - Detlef Lohse
- Max Planck Institute for Dynamics and Self-Organization, 37077 Göttingen, Germany
- Physics of Fluids Group, J. M. Burgers Center for Fluid Dynamics and MESA+ Institute, University of Twente, 7500 AE Enschede, Netherlands
- Max Planck-University of Twente Center for Complex Fluid Dynamics, 7500 AE Enschede, Netherlands
| | - Philipp Reiter
- Max Planck Institute for Dynamics and Self-Organization, 37077 Göttingen, Germany
| | - Richard J A M Stevens
- Physics of Fluids Group, J. M. Burgers Center for Fluid Dynamics and MESA+ Institute, University of Twente, 7500 AE Enschede, Netherlands
| | - Roberto Verzicco
- Physics of Fluids Group, J. M. Burgers Center for Fluid Dynamics and MESA+ Institute, University of Twente, 7500 AE Enschede, Netherlands
- Dipartimento di Ingegneria Industriale, University of Rome "Tor Vergata," Via del Politecnico 1, Roma 00133, Italy
- Gran Sasso Science Institute-Viale F. Crispi, 767100 L'Aquila, Italy
| | - Marcel Wedi
- Max Planck Institute for Dynamics and Self-Organization, 37077 Göttingen, Germany
| | - Stephan Weiss
- Max Planck Institute for Dynamics and Self-Organization, 37077 Göttingen, Germany
- Max Planck-University of Twente Center for Complex Fluid Dynamics, 7500 AE Enschede, Netherlands
| | - Xuan Zhang
- Max Planck Institute for Dynamics and Self-Organization, 37077 Göttingen, Germany
| | - Lukas Zwirner
- Max Planck Institute for Dynamics and Self-Organization, 37077 Göttingen, Germany
| | - Olga Shishkina
- Max Planck Institute for Dynamics and Self-Organization, 37077 Göttingen, Germany
| |
Collapse
|
6
|
Zwirner L, Emran MS, Schindler F, Singh S, Eckert S, Vogt T, Shishkina O. Dynamics and length scales in vertical convection of liquid metals. JOURNAL OF FLUID MECHANICS 2022; 932:A9. [DOI: 10.1017/jfm.2021.977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
Using complementary experiments and direct numerical simulations, we study turbulent thermal convection of a liquid metal (Prandtl number
$\textit {Pr}\approx 0.03$
) in a box-shaped container, where two opposite square sidewalls are heated/cooled. The global response characteristics like the Nusselt number
${\textit {Nu}}$
and the Reynolds number
$\textit {Re}$
collapse if the side height
$L$
is used as the length scale rather than the distance
$H$
between heated and cooled vertical plates. These results are obtained for various Rayleigh numbers
$5\times 10^3\leq {\textit {Ra}}_H\leq 10^8$
(based on
$H$
) and the aspect ratios
$L/H=1, 2, 3$
and
$5$
. Furthermore, we present a novel method to extract the wind-based Reynolds number, which works particularly well with the experimental Doppler-velocimetry measurements along vertical lines, regardless of their horizontal positions. The extraction method is based on the two-dimensional autocorrelation of the time–space data of the vertical velocity.
Collapse
|
7
|
Hu YB, Huang SD, Xie YC, Xia KQ. Centrifugal-Force-Induced Flow Bifurcations in Turbulent Thermal Convection. PHYSICAL REVIEW LETTERS 2021; 127:244501. [PMID: 34951813 DOI: 10.1103/physrevlett.127.244501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Revised: 08/01/2021] [Accepted: 11/08/2021] [Indexed: 06/14/2023]
Abstract
An important and unresolved issue in rotating thermal turbulence is when the flow starts to feel the centrifugal effect. This onset problem is studied here by a novel experiment in which the centrifugal force can be varied over a wide range at fixed Rossby numbers by offsetting the apparatus from the rotation axis. Our experiment clearly shows that the centrifugal force starts to separate the hot and cold fluids at the onset Froude number 0.04. Additionally, this flow bifurcation leads to an unexpected heat transport enhancement and the existence of an optimal state. Based on the dynamical balance and characteristics of local flow structures, both the onset and optimal states are quantitatively explained.
Collapse
Affiliation(s)
- Yun-Bing Hu
- Center for Complex Flows and Soft Matter Research and Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen 518055, China
- Department of Physics, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Shi-Di Huang
- Center for Complex Flows and Soft Matter Research and Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen 518055, China
- Department of Physics, The Chinese University of Hong Kong, Shatin, Hong Kong, China
- Guangdong Provincial Key Laboratory of Turbulence Research and Applications, Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Yi-Chao Xie
- Department of Physics, The Chinese University of Hong Kong, Shatin, Hong Kong, China
- State Key Laboratory for Strength and Vibration of Mechanical Structures and School of Aerospace, Xi'an Jiaotong University, Xi'an 710049, China
| | - Ke-Qing Xia
- Center for Complex Flows and Soft Matter Research and Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen 518055, China
- Department of Physics, The Chinese University of Hong Kong, Shatin, Hong Kong, China
- Guangdong Provincial Key Laboratory of Turbulence Research and Applications, Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| |
Collapse
|
8
|
Wang Q, Verzicco R, Lohse D, Shishkina O. Multiple States in Turbulent Large-Aspect-Ratio Thermal Convection: What Determines the Number of Convection Rolls? PHYSICAL REVIEW LETTERS 2020; 125:074501. [PMID: 32857539 DOI: 10.1103/physrevlett.125.074501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 07/20/2020] [Indexed: 06/11/2023]
Abstract
Wall-bounded turbulent flows can take different statistically stationary turbulent states, with different transport properties, even for the very same values of the control parameters. What state the system takes depends on the initial conditions. Here we analyze the multiple states in large-aspect ratio (Γ) two-dimensional turbulent Rayleigh-Bénard flow with no-slip plates and horizontally periodic boundary conditions as model system. We determine the number n of convection rolls, their mean aspect ratios Γ_{r}=Γ/n, and the corresponding transport properties of the flow (i.e., the Nusselt number Nu), as function of the control parameters Rayleigh (Ra) and Prandtl number. The effective scaling exponent β in Nu∼Ra^{β} is found to depend on the realized state and thus Γ_{r}, with a larger value for the smaller Γ_{r}. By making use of a generalized Friedrichs inequality, we show that the elliptical shape of the rolls and viscous damping determine the Γ_{r} window for the realizable turbulent states. The theoretical results are in excellent agreement with our numerical finding 2/3≤Γ_{r}≤4/3, where the lower threshold is approached for the larger Ra. Finally, we show that the theoretical approach to frame Γ_{r} also works for free-slip boundary conditions.
Collapse
Affiliation(s)
- Qi Wang
- Physics of Fluids Group and Max Planck Center for Complex Fluid Dynamics, MESA+ Institute and J. M. Burgers Centre for Fluid Dynamics, University of Twente, P.O. Box 217, 7500AE Enschede, Netherlands
- Department of Modern Mechanics, University of Science and Technology of China, Hefei 230027, China
| | - Roberto Verzicco
- Physics of Fluids Group and Max Planck Center for Complex Fluid Dynamics, MESA+ Institute and J. M. Burgers Centre for Fluid Dynamics, University of Twente, P.O. Box 217, 7500AE Enschede, Netherlands
- Dipartimento di Ingegneria Industriale, University of Rome "Tor Vergata", Via del Politecnico 1, 00133 Roma, Italy
- Gran Sasso Science Institute-Viale F. Crispi, 767100 L'Aquila, Italy
| | - Detlef Lohse
- Physics of Fluids Group and Max Planck Center for Complex Fluid Dynamics, MESA+ Institute and J. M. Burgers Centre for Fluid Dynamics, University of Twente, P.O. Box 217, 7500AE Enschede, Netherlands
- Max Planck Institute for Dynamics and Self-Organization, 37077 Göttingen, Germany
| | - Olga Shishkina
- Max Planck Institute for Dynamics and Self-Organization, 37077 Göttingen, Germany
| |
Collapse
|