Three-Dimensional Numerical Analysis of Transient Natural Convection in Rectangular Enclosures

A simple numerical technique of considerable practical utility for the solution of transient multidimensional natural convection problems is described. It is based on the solution of the conservation equations in primitive form. The technique can be extended to calculation of natural convection problems in porous media and in turbulent flows where the eddy viscosities and conductivities can be predicted. It has been applied to the solution of several two and three-dimensional natural convection problems. The solutions compare well with the numerical and experimental results published by other investigators.

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Erratum: “Three-Dimensional, Numerical Analysis of Laminar Natural Convection in a Confined Fluid Heated From Below” (Journal of Heat Transfer, 1976, 98, pp. 202–207)

Journal of Heat Transfer ◽

10.1115/1.3450588 ◽

1976 ◽

Vol 98 (3) ◽

pp. 519-519 ◽

Cited By ~ 5

Author(s):

H. Ozoe ◽

K. Yamamoto ◽

S. W. Churchill ◽

H. Sayama

Keyword(s):

Heat Transfer ◽

Natural Convection ◽

Numerical Analysis ◽

Three Dimensional ◽

Confined Fluid ◽

Laminar Natural Convection

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Numerical Simulation Study on the Asymmetric Structures of Oscillatory Flow Field in a Baffled Tube Reactor

Computational Technologies for Fluid/Thermal/Structural/Chemical Systems With Industrial Applications, Volume 2 ◽

10.1115/pvp2004-3139 ◽

2004 ◽

Cited By ~ 1

Author(s):

Yong-Wen Wu ◽

Jia Wu

Keyword(s):

Numerical Simulation ◽

Turbulent Flows ◽

Oscillatory Flow ◽

Numerical Technique ◽

Three Dimensional ◽

Structured Grid ◽

Tube Reactor ◽

Oscillating Boundary ◽

The Asymmetry ◽

Laminar And Turbulent Flows

The oscillatory flow in a baffled tube reactor provides a significant enhancement of radial transfer of momentum, heat and mass and a good control of axial back mixing at a wide range of net flow rate. But little has been known about reliable details of the three-dimensional structure of flow field in this kind of flow because most published studies in the area were based on the two-dimensional simulation techniques. This paper implemented a three-dimensional numerical simulation study on the asymmetry of flow pattern in the baffled tube reactor which was observed experimentally. A systematic study by numerical simulation was carried out which covered a range of oscillatory Reynolds number (Reo) from 100 to 5,000 and employed models respectively for laminar and turbulent flows. It was found in the simulation that under symmetric boundary conditions the transition from axially symmetric flow to asymmetric one depended on the numerical technique employed in simulation. With a structured grid frame the transition occurred at Reo much greater than that with an unstructured grid frame, for both laminar and turbulent flows. It is not rational that the onset of the transition changes with the accuracy of numerical technique. Based on the simulation results, it was postulated that the asymmetry appeared in simulations with symmetric boundary conditions might result from the accumulation of calculation errors but the asymmetry observed in experiments might result from the slight asymmetry of geometry which exists inevitably in any experiment apparatus. To explore the influence of the slight asymmetry of geometry, the effect of the eccentricity of baffles and the declination of oscillating boundary were studied by use of the finite volume method with a structured grid and adaptive time steps. The simulation result showed that both the eccentricity of baffles and the declination of oscillating boundary have obvious influence on the asymmetry of flow patterns for laminar and turbulent flow. More details were discussed in the paper.

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A Numerical Analysis of Three-Dimensional Compressible Turbulent Flows in Cascades and Ducts

Computational Methods and Experimental Measurements ◽

10.1007/978-3-662-06375-0_2 ◽

1984 ◽

pp. 19-30 ◽

Cited By ~ 1

Author(s):

Y. Shikano ◽

M. Ikegawa ◽

S. Nakano

Keyword(s):

Numerical Analysis ◽

Turbulent Flows ◽

Three Dimensional

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Three-Dimensional Numerical Analysis for Convection of Air in a Bore Space of a Superconducting Magnet

Volume 2: Symposia, Parts A, B, and C ◽

10.1115/fedsm2003-45043 ◽

2003 ◽

Author(s):

G. Tomita ◽

M. Kaneda ◽

T. Tagawa ◽

H. Ozoe

Keyword(s):

Magnetic Field ◽

Heat Flux ◽

Natural Convection ◽

Numerical Analysis ◽

Strong Magnetic Field ◽

Three Dimensional ◽

Superconducting Magnet ◽

Constant Heat Flux ◽

Constant Heat ◽

Magnetizing Force

Three-dimensional numerical computations were carried out for the natural convection of air in a horizontal cylindrical enclosure in a magnetic field, which is modeled for a bore space of a horizontal superconducting magnet. The enclosure was cooled from the circumferential sidewall at the constant heat flux and vertical end walls were thermally insulated. A strong magnetic field was considered by a one-turn electric coil with the concentric and twice diameter of the cylinder. Without a magnetic field, natural convection occurs along the circumferential sidewall. When a magnetic field was applied, magnetizing force induced the additional convection, that is, the cooled air at the circumferential wall was attracted to the location of a coil. Consequently, the temperature around the coil decreased extensively.

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