Let suppose that for initial time slit is filed with a high temperature fluid. Then we can compute convection in a slit and in a reservoir ... ... <看更多>
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Let suppose that for initial time slit is filed with a high temperature fluid. Then we can compute convection in a slit and in a reservoir ... ... <看更多>
瑞利數(Rayleigh number),是流體力學中的無量綱數,指自然對流和擴散熱量、動量傳遞之比,計算式為:. R a = G r P r = g β Δ T L 3 ν α {\displaystyle \mathrm ...
#2. Rayleigh Number - an overview | ScienceDirect Topics
The Rayleigh number measures the ratio of buoyancy to viscous forces in the fluid. From: Encyclopedia of Physical Science and Technology (Third Edition), 2003 ...
#3. Rayleigh Number | Definition, Formula & Calculation
The Rayleigh number is a dimensionless number named after Lord Rayleigh. The Rayleigh number is closely related to the Grashof number, and both numbers are ...
#4. Rayleigh number
Rayleigh number, Ra, is a dimensionless term used in the calculation of natural convection. where g is acceleration due to gravity, β' is coefficient of thermal ...
#5. Rayleigh number
Rayleigh number is a dimensionless number that represents the ratio of buoyancy and thermal diffusivity. It can be obtained by the following equation:.
#6. Rayleigh number: Definition, Significance, Formula ...
What is Rayleigh number? Rayleigh number is defined as the product of grashof number and Prandtl number. The rayleigh number is denoted by the symbol Ra.
#7. How Rayleigh's number links conduction and convection
The Rayleigh number can be interpreted conceptually as the dimensionless parameter that measures the relative importance between the effects of ...
#8. The Grashof Number and the Rayleigh Number - YouTube
The Grashof Number and the Rayleigh Number. 13K views · 4 years ago ...more. MECH 346 – Heat Transfer. 1.06K. Subscribe. 1.06K subscribers.
#9. High-Rayleigh-number thermal convection of compressed ...
High-Rayleigh-number convection is experimentally studied using compressed gases for a wide range of Rayleigh numbers (1.85 × 106 ≤ Ra ...
#10. Rayleigh number - Glossary of Meteorology
The Rayleigh number is equal to the product of the Grashoff and Prandtl numbers, and is the critical parameter in the theory of thermal ...
#11. What is the physical significance of Rayleigh number?
Rayleigh number is the property of a fluid that determines how heat is transferred throughout the fluid. When you have a mass of fluid with an uneven ...
#12. Rayleigh number
In fluid mechanics, the Rayleigh number for a fluid is a dimensionless number associated with the heat transfer within the fluid. When the Rayleigh number ...
#13. Rayleigh Number -- from Eric Weisstein's World of Physics
The critical Rayleigh number actually turns out to be much larger than indicated in this simple calculation. In the Bénard configuration (fixed top surface), ...
#14. An Explanation to the Nusselt–Rayleigh Discrepancy in ...
The Rayleigh number is set as 42.25, slightly above the critical Rayleigh number, such that the system starts convecting. The initial condition ...
#15. High Rayleigh number convection in a three-dimensional ...
High-resolution numerical simulations of statistically steady convection in a three-dimensional porous medium are presented for Rayleigh numbers Ra⩽2×104.
#16. Rayleigh number | physics
If the Rayleigh number is less than 1,708, the fluid is stable—or perhaps it would be more accurate to say that it is metastable—even though it ...
#17. Rayleigh number
In fluid mechanics, the Rayleigh number for a fluid is a dimensionless number associated with buoyancy driven flow (also known as free convection or natural ...
#18. Rayleigh Number: Most Up-to-Date Encyclopedia ...
In fluid mechanics, the Rayleigh number of a fluid (Ra, after Lord Rayleigh) is a dimensionless number related to buoyancy-driven flow, also known as free ...
#19. Regime transitions in thermally driven high-Rayleigh ...
... of Rayleigh numbers 10^7\le Ra\le10^{14} with fixed Prandtl number Pr=10, in a two-dimensional convection cell with unit aspect ratio.
#20. High Rayleigh Number Convection
High Rayleigh Number Convection. Annual Review of Fluid Mechanics. Vol. 26:137-168 (Volume publication date January 1994)
#21. Rayleigh Number - calculator
In fluid mechanics, the Rayleigh number (Ra) for a fluid is a dimensionless number associated with buoyancy driven flow (also known as free convection or ...
#22. 5.2 Rayleigh Number – Variable-Density Groundwater Flow
The Rayleigh number is the ratio between buoyancy-driven forces that drive free convection to forces (caused by diffusion and dispersion) that act to ...
#23. [Calculation of the concentration Rayleigh number for ...
A method of determination critical value of concentration Rayleigh Number ((Rci)lim.) in isothermal membrane transport processes of three component ...
#24. Derivation of Rayleigh Number for Nonpenetrative Thermal ...
D. L.. ,. 1990. , “. High-Rayleigh-Number Convection in a Horizontal Enclosure. ,”. Journal of Fluid Mechanics. , ...
#25. Rayleigh number
Rayleigh number (Ra) A dimensionless value used to estimate when convection commences in a fluid. The Ra depends on the density and depth of the fluid, ...
#26. Local Nusselt number versus local Rayleigh number, S/H = ...
Download scientific diagram | Local Nusselt number versus local Rayleigh number, S/H = 0 . 3. from publication: Comparative measurements of natural ...
#27. Influence of Rayleigh Number in Turbulent and Laminar ...
To study the influence of Rayleigh number on the flow field and heat transfer characteristics, the vertical velocity and temperature profiles as well as the ...
#28. About: Rayleigh number
In fluid mechanics, the Rayleigh number (Ra, after Lord Rayleigh) for a fluid is a dimensionless number associated with buoyancy-driven flow, also known as ...
#29. RayLeigh Number | PDF | Viscosity | Heat Transfer
RayLeigh number - Free download as Word Doc (.doc), PDF File (.pdf), Text File (.txt) or read online for free. Fluid mechanics.
#30. Rayleigh-number evolution of large-scale coherent motion in ...
Rayleigh -number evolution of large-scale coherent motion in turbulent convection. J. J. Niemela 1 and K. R. Sreenivasan 1. 2003 EDP Sciences
#31. Rayleigh Number
Rayleigh number, abbreviated as Ra, a dimensionless number, is associated with free or natural convection. It is a modified Grashof number ...
#32. Rayleigh number -- CFD-Wiki, the free CFD reference
The Rayleigh number is the ratio of the buoyancy force to the viscous force in a medium. Ra = \frac{g \alpha \Gamma d^4}{\. where g = ...
#33. Grashof Number and Rayleigh Number
The most important use of the Rayleigh number is to characterize the laminar to turbulence transition of a free convection boundary layer flow. For example, ...
#34. Rayleigh Number Using Thermal Diffusivity
The Rayleigh number for a fluid is a dimensionless number associated with buoyancy-driven flow, also known as free convection or natural convection.
#35. Finite element calculations of very high Rayleigh number ...
Summary. A finite element method with uniform and variable resolution meshes is used to model very high Rayleigh number Ra thermal convection in a square ...
#36. [Solved] The Rayleigh number Ra, is defined as: (where Gr ...
The product of Grashof number and Prandtl No is called Rayleigh number. ... Explanation: Biot Number (Bi): ... Sherwood number (Sh): The ratio of ...
#37. UPPER AND LOWER RAYLEIGH NUMBER BOUNDS FOR ...
... from a heated upward facing finite horizontal surface in a fluid-saturated porous medium. The Rayleigh number range for which two-dimensional fl...
#38. Ocean 540: Convective Heat Transfer
Oceanography 540--Marine Geological Processes--Autumn Quarter 2002. Convection and Rayleigh Criteria. To motivate the Rayleigh number, ...
#39. Critical Rayleigh Numbers for Natural Convection of Water ...
Rayleigh numbers ivhich are distinct functions of the L/D of the liquid. ... tures of the warm and cold boundaries, if the Rayleigh number is calculated as ...
#40. In fluid mechanics, the Rayleigh number for a ...
When the Rayleigh number is below the critical value for that fluid, heat transfer is primary in the form of conduction; when it exceeds the critical value, ...
#41. Rayleigh number for long slit heated at the end
Let suppose that for initial time slit is filed with a high temperature fluid. Then we can compute convection in a slit and in a reservoir ...
#42. Rayleigh Number
is the thermal diffusivity. No convective motion occurs at low values of the Rayleigh number, Ra < 1708, and the fluid transports heat exclusively by molecular ...
#43. On Moderate-Rayleigh-Number Convection in an Inclined ...
We investigate the flow structure and dynamics of moderate-Rayleigh-number ( R a ) thermal convection in a two-dimensional inclined porous layer.
#44. Rayleigh-Bénard Convection
Researchers use the Rayleigh number to measure the “amount of convection” in a flow. This number helps researchers compare results between experiments ...
#45. High Rayleigh Number Convection - Physics Courses
From the onset of convection up to Rayleigh numbers Ra . 10 times ... of Reynolds number has dominated studies of the boundary layer. Both.
#46. Rayleigh Number
analysis is complicated by uncertainties regarding the specific formulation of both the mush-Rayleigh number itself and of the sea-ice ...
#47. Lower Bounds to the Critical Rayleigh Number in ...
Minimum Rayleigh number that will induce a state of convective motion in a Boussinesq fluid where temperature gradient is in direction of body force.
#48. The Rayleigh number for convection in the Earth's core
Geodynamo models depend on two important parameters: the Ekman and Rayleigh numbers. While the difficulty of simulating a geodynamo with very small Ekman ...
#49. Rayleigh number (Re)
This dimensionless number determines the type of airflow (laminar, transition, or turbulent along a heated fin surface). When the Rayleigh number is below ...
#50. NUMERICAL SIMULATIONS OF CONVECTIVE HEAT ...
cies characterized by correlations of Nusselt number with Rayleigh number (Nu$Rac); ... important dimensionless groups, the Rayleigh and Prandtl numbers, ...
#51. High Rayleigh number thermal convection
High Rayleigh number thermal convection. Heat transfer in a Rayleigh- Bénard system can satisfactory be described by the Grossmann-Lohse (GL) theory.
#52. Rayleigh number
quantity. Rayleigh number. Instance information. -. comment. The Rayleigh number for a fluid is a dimensionless number associated with buoyancy driven flow.
#53. Prandtl and Rayleigh number dependence of the Reynolds ...
The Prandtl and Rayleigh number dependences of the Reynolds number in turbulent thermal convection following from the unifying theory by ...
#54. High Rayleigh Number Convection in Rectangular ...
investigation for high Rayleigh number natural convection flows for an arbi- trary aspect ratio ( 0 < E 5 1). Most of the reported work has been done on very ...
#55. On the effects of Rayleigh number and inlet turbulence ...
On the effects of Rayleigh number and inlet turbulence intensity upon the buoyancy-induced mass flow rate in sloping and convergent channels.
#56. High-Rayleigh-number convection in a fluid-saturated porous ...
Over an intermediate range of increasing Rayleigh numbers, the simulations display the 'classical' heat transport Nu ∼ Ra scaling. As the Rayleigh number is ...
#57. Rayleigh number
characteristic number of heat transport in fluids. In more languages. Spanish. número de Rayleigh. No description defined. Traditional Chinese.
#58. Lecture 2 1 Description of the Rayleigh B\enard instability
щN is also a numerical coefficient. When the ratio between these two powers exceeds a critical value convection occurs. We define the Rayleigh number by.
#59. High Rayleigh number convection in enclosed fluid layers ...
Amazon.com: High Rayleigh number convection in enclosed fluid layers with internal heat sources: Kulacki, F. A.: Books.
#60. The impact of Rayleigh number on assessing the significance ...
Broad, hot upper mantle features generated in low‒Rayleigh number models (due, in part, to the thermal blanket effect) are absent at higher ...
#61. Classical 1/3 scaling of convection holds up to Ra = 1015
We cover Rayleigh numbers in the range 108≤Ra≤1015 at the Prandtl number Pr held fixed at unity, such that the momentum and thermal boundary layers have ...
#62. Effect of Rayleigh Number with Rotation on Natural ...
Key words: Rayleigh number; Taylor number; Rotating enclosure; Natural convection; Coriolis force. NOMENCLATURE. Dimensionless Centrifugal Force.
#63. How to do a parametric sweep with the Rayleigh number?
How to do a parametric sweep with the Rayleigh number? Posted Jul 31, 2020, 6:25 p.m. EDT Fluid & Heat, Computational Fluid Dynamics (CFD), Parameters, ...
#64. Turbulent convection at very high Rayleigh numbers
For a Newtonian fluid, the dynamical state of convection is governed by the Rayleigh number Ra ≡ gαΔ TL 3 νκ and the Prandtl number Pr ≡ ν/κ.
#65. Turbulent convection at very high Rayleigh numbers
Here we investigate thermal transport over eleven orders of magnitude of the Rayleigh number (106 # Ra # 107), using cryogenic helium gas as the working fluid.
#66. Measurement of Local Hot-Wall Heat Transfer in High ...
Representative results illustrating the effects of the enclosure inclination angle and the Hartmann number for two different Rayleigh numbers on the contour ...
#67. The Critical Rayleigh Number in Low Gravity Crystal Growth ...
If crystal growth from solution takes place in a closed container, a critical Rayleigh number can be defined, below which buoyancy driven ...
#68. Numerical study of high Rayleigh number convection in a ...
The purpose of this paper is systematically to explore the effect that depth-dependent viscosity has on thermal convection at high Rayleigh numbers. The models ...
#69. High Rayleigh Number Thermal Convection
High Rayleigh Number Thermal Convection. 10 - 20 June 2003. Venue: Lorentz Center@Oort. If you are invited or already registered for this workshop, ...
#70. Effects of Rayleigh Number on MHD Heat Transfer and ...
To find the effects of Rayleigh number (Ra) on the thermal fields and fluid flow in presence of magnetic field and a heated circular cylinder as heat source ...
#71. On the Low Rayleigh Number Asymptote for Natural ...
Title, On the Low Rayleigh Number Asymptote for Natural Convection Through an Isothermal, Parallel-Plate Channel. Publication Type, Book Chapter.
#72. Development of a Freckle Predictor via Rayleigh Number ...
If the Rayleigh number in a superalloy casting is below this critical value, freckles are not expected to form. Full numerical simulations of.
#73. 520 – High Rayleigh number convection
ultimate regime in Rayleigh Bénard convection; convection in non Boussinesq flows; low and high Prandtl number flow; convective mixing; large scale flow ...
#74. h‐adaptive finite element solution of high Rayleigh number ...
h‐adaptive finite element solution of high Rayleigh number thermally driven cavity problem - Author: David A. Mayne, Asif S. Usmani, Martin Crapper.
#75. Simulation of Turbulent Convection at High Rayleigh ...
It is shown that, at Rayleigh numbers from 10 9 to 10 17, the application of the eddy-resolving LES model makes it possible to substantially increase the accuracy ...
#76. High Rayleigh Number Convection in Enclosed Fluid Layers ...
The Rayleigh number range of the reported data of the Jahn and Reineke correlation was 5 x 105 Ra≤ 5 x 108 and thus overlaps the Rayleigh number range of ...
#77. Experimental and numerical investigation of high–Rayleigh ...
High–Rayleigh number convective turbulence is ubiquitous in many natural phenomena and in industries, such as atmospheric circulations, oceanic flows, ...
#78. High Rayleigh number convection in a three ... - DAMTP
High-resolution numerical simulations of statistically steady convection in a three- dimensional porous medium are presented for Rayleigh numbers Ra ⩽ 2 ...
#79. Curvature Effect on the Critical Rayleigh Number for the ...
In the present study, curvature effects on the critical Rayleigh number Rac for the instability of natural convection boundary layers of Pr=7 on ...
#80. Onset of Natural Convection and Transition Laminar- ...
They focused on fluid in the supercritical state and depicted the critical Rayleigh number at 2585 in a square cavity. They focused also on the sensibility of ...
#81. Plume structure in high-Rayleigh-number convection
near-wall boundary layers associated with each sheet plume in high-Rayleigh-number turbulent natural convection are likely to be laminar mixed convection ...
#82. Browsing Issue 01 by Subject "Concentration Rayleigh Number"
Browsing Issue 01 by Subject "Concentration Rayleigh Number" ... The present paper purports to deal with the problem of triply diffusive convection in sparsely ...
#83. Mathematical modelling of mantle convection at a high ...
[21], numerical simulations of 3D convection with temperature-dependent viscosity and viscous heating at realistic Rayleigh numbers for Earth's ...
#84. Turbulent convection at very high Rayleigh numbers
Turbulent convection occurs when the Rayleigh number (Ra)--which quantifies the relative magnitude of thermal driving to dissipative forces in the fluid ...
#85. High-Rayleigh-number convection in porous–fluid layers
We explore the dynamics and heat flux through the system in the limit of large Rayleigh number, but small Darcy number, such that the flow ...
#86. Flow at Ultra-High Reynolds and Rayleigh Numbers: A Status ...
The question to ask is: how high a Reynolds or Rayleigh number is attained in situations of interest to us? We shall consider some specific examples to ...
#87. Dimensional Natural Convection High-Rayleigh Number
At Rayleigh numbers greater than 104 and aspect ratios near 1, the laminar boundary layer regime exists. The heat transfer mechanism is convection in ...
#88. A boundary-layer analysis of Rayleigh-Benard convection ...
of an infinite-Prandtl-number fluid in a rectangular enclosure, in the limit of large. Rayleigh numbers. Particular emphaais is given to the analysis of the ...
#89. Mushy-Zone Rayleigh Number to Describe Macrosegregation ...
Mushy-Zone Rayleigh Number to Describe Macrosegregation and Channel Segregate Formation During Directional Solidification of Metallic Alloys. Metallurgical and.
#90. CRITICAL RAYLEIGH NUMBER IN ...
CRITICAL RAYLEIGH NUMBER. IN RAYLEIGH-BЙNARD CONVECTION. By. YAN GUO ( Division of Applied Mathematics, Brown University, Providence, ...
#91. Solved (a) How does the Rayleigh number differ from the
(a) How does the Rayleigh number differ from the Grashof number? (b) The outer surface of an engine is situated in a place where oil leakage can occur.
#92. Onset of Rayleigh-Benard Convection in CO2 ...
It is also observed that the ratio of thermal diffusivity to mass diffusivity (the Lewis Number), lower values of the Damköhler number and the ...
#93. Rayleigh Number in a Stability Problem for a Micropolar Fluid
Approximate numerical evaluations of the Rayleigh number are obtained for a stability problem of thermal convection in a heat-conducting micropolar fluid ...
#94. Heat Transfer: A Problem Solving Approach
For the downward facing surface , the Rayleigh number is again calculated via Eq . ( 8.2.15 ) . Unlike the upward facing surface , for higher values of RaL ...
#95. Internally Heated Convection and Rayleigh-Bénard Convection
The Rayleigh number may be thought of as the ratio of inertial forces to viscous forces. When it is large, the fluid is strongly driven by differential ...
#96. Linear Theory of Particulate Rayleigh-Bénard Stability
The effect of the particles is explored by varying the number density, the mechanical and thermal Stokes numbers and ratio of the particle to fluid densities ...
#97. OTS. - 第 75-50017 期 - 第 191 頁 - Google 圖書結果
The parameter y occurring in these formulas is a function of the Rayleigh number : y = R [ 1 + a3N + e ( 1 + a2N + ) ] . ( 31.10 ) The critical value of y ...
#98. [PDF] Transitions in the style of mantle convection at high ...
Semantic Scholar extracted view of "Transitions in the style of mantle convection at high Rayleigh numbers" by D. Weeraratne et al.
rayleigh number 在 The Grashof Number and the Rayleigh Number - YouTube 的推薦與評價
The Grashof Number and the Rayleigh Number. 13K views · 4 years ago ...more. MECH 346 – Heat Transfer. 1.06K. Subscribe. 1.06K subscribers. ... <看更多>