Turbulent vertical convection under vertical vibration

Guo, Xin-Qian1; Wang, Bo-Fu1,2; Wu, Jian-Zhao1; Chong, Kai Leong1; Zhou, Quan1

2022-05-01

10.1063/5.0090250

PHYSICS OF FLUIDS   影响因子和分区

1070-6631

1089-7666

Vertical convection (VC) under the action of vertical vibration in a square cavity has been investigated using direct numerical simulation. The simulations are conducted with Prandtl number Pr fixed at 4.38 and Rayleigh number Ra ranging from 10(8) to 10(10). To examine the influence of vertical vibration, the dimensionless vibration frequency is varied in the range of 0 <=& nbsp;omega <=& nbsp;1000 and a small dimensionless amplitude is fixed at a = 1.52 x 10(-3). First, for low vibration frequency, trivial results are obtained where flow structures and the scalings of Nu and Re resemble that of the standard VC cases. In contrast, when the vibration frequency omega increases beyond a critical value omega*, a strong shearing effect from vibration leads to abundant eruptions of thermal plumes from sidewalls, and thus a laminar-turbulent transition of the bulk flow. As a result, heat-transport is greatly enhanced and the scaling exponent beta of Nu ~& nbsp;Ra-beta substantially increases in such the vibration-dominated regime. In specific, the scaling relations obtained transit from Nu ~& nbsp;Ra-0.25 and Re ~& nbsp;Ra-0.37 at omega = 0 in the laminar regime to Nu ~& nbsp;Ra-0.42 and Re ~& nbsp;Ra-0.52 at omega ?& nbsp;300 in the turbulent regime. Analysis of the mean flow field shows that the vibration thins the thermal boundary layer and enhances the thermal dissipation rate in the bulk region. Furthermore, we found that the trend of Nu and Re can be well described by the vibrational Rayleigh number Ra-vib. In particular, Nu is insensitive to Ra-vib for Ra-vib & nbsp;>& nbsp;Ra-vib*, whereas Nu(omega)/Nu(0) ~& nbsp;(Ra-vib/Ra-vib*)(0.42) for Ra-vib > Ra-vib*, where the critical vibrational Rayleigh number exhibits a scaling relation Ra-vib* ~& nbsp;Ra-0.68 obtained from numerical results. (C)& nbsp;2022 Author(s).

SCI ; EI

英语

通讯

Natural Science Foundation of China[11988102,92052201,91852202,11825204,12102246,11972220] ; Program of Shanghai Academic Research Leader[19XD1421400] ; Shanghai Science and Technology Program["19JC1412802","20ZR1419800"] ; Shanghai Pujiang Program[21PJ1404400] ; China Postdoctoral Science Foundation[2020M681259] ; Guangdong Provincial Key Laboratory[2019B121203001]

Mechanics ; Physics

Mechanics ; Physics, Fluids & Plasmas

WOS:000795706900014

AIP Publishing

20222112134085

Atmospheric thermodynamics ; Boundary layers ; Thermal plumes ; Vibration analysis

Atmospheric Properties:443.1 ; Thermodynamics:641.1 ; Heat Transfer:641.2 ; Physical Properties of Gases, Liquids and Solids:931.2

PHYSICS

Web of Science

1.Shanghai Univ, Shanghai Inst Appl Math & Mech, Sch Mech & Engn Sci, Shanghai Key Lab Mech Energy Engn, Shanghai 200072, Peoples R China
2.Southern Univ Sci & Technol, Guangdong Prov Key Lab Turbulence Res & Applicat, Shenzhen 518055, Peoples R China

Guo, Xin-Qian,Wang, Bo-Fu,Wu, Jian-Zhao,et al.

Turbulent vertical convection under vertical vibration

[J]. PHYSICS OF FLUIDS,2022,34(5).

Guo, Xin-Qian,Wang, Bo-Fu,Wu, Jian-Zhao,Chong, Kai Leong,&Zhou, Quan.(2022).

Turbulent vertical convection under vertical vibration

.PHYSICS OF FLUIDS,34(5).

Guo, Xin-Qian,et al."

Turbulent vertical convection under vertical vibration

".PHYSICS OF FLUIDS 34.5(2022).