Numerical investigation of natural convection with the presence of surface roughness or complex geometries

This paper represents a numerical study of mixed convection conduction in enclosed two- dimensional square cavity differentially heated. Complex geometries are designed on a vertical partitioned wall, those geometries are applied to building facades aiming to improve the overall energy performance of the building. Our numerical results are based on the resolution of coupled momentum and energy equations using Ansys Fluent. Numerical study has been performed for different values of the Rayleigh number. Triangular geometry element will be considered in the middle wall. Finally, temperature profile and streamlines will be analyzed to examine the influence of this studied shape.

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A Numerical Study of Natural Convection in a Cavity With Two Fins Attached to Its Vertical Walls

Volume 8: Heat Transfer, Fluid Flows, and Thermal Systems, Parts A and B ◽

10.1115/imece2007-43210 ◽

2007 ◽

Author(s):

G. A. Sheikhzadeh ◽

M. Pirmohammadi ◽

M. Ghassemi

Keyword(s):

Nusselt Number ◽

Natural Convection ◽

Rayleigh Number ◽

Numerical Study ◽

Convection Heat Transfer ◽

Square Cavity ◽

Vertical Walls ◽

The Mean ◽

Energy Equations ◽

Rayleigh Numbers

Numerical study natural convection heat transfer inside a differentially heated square cavity with adiabatic horizontal walls and vertical isothermal walls is investigated. Two perfectly conductive thin fins are attached to the isothermal walls. To solve the governing differential mass, momentum and energy equations a finite volume code based on Pantenkar’s simpler method is developed and utilized. The results are presented in form of streamlines, isotherms as well as Nusselt number for Rayleigh number ranging from 104 up to 107. It is shown that the mean Nusselt number is affected by the position of the fins and length of the fins as well as the Rayleigh number. It is also observed that maximum Nusselt number occurs about the middle of the enclosure where Lf is grater the 0.5. In addition the Nusselt number stays constant and does not varies with width of the cavity (lf) when Lf is equal to 0.5 and Rayleigh number is equal to 104 and 107 as well as when Lf is equal to 0.6 and low Rayleigh numbers.

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Numerical Study Regarding the Flow Movement in Natural Convection in an Asymmetrical Heated Vertical Channel

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.659.319 ◽

2014 ◽

Vol 659 ◽

pp. 319-324 ◽

Cited By ~ 1

Author(s):

Andrei Burlacu ◽

Marina Verdeș ◽

Vasilică Ciocan ◽

Cătălin George Popovici ◽

Marius Costel Balan ◽

...

Keyword(s):

Fluid Dynamics ◽

Natural Convection ◽

Single Channel ◽

Numerical Study ◽

Vertical Channel ◽

The Other ◽

Heat Output ◽

Ansys Fluent ◽

Energy Equations ◽

Physical Boundary

The present paper presents a numerical study, regarding the dynamics of movement in natural convection in an asymmetrically heated vertical channel. The channel was immersed in a tank filled with water at a temperature of 15 °C. The study focuses on one hand, on the radiated heat output from the heating plate, and on the other hand, on the thermo-physical boundary conditions from the inlet and the outlet of the channel. These aspects give great problems in natural convection if limited to a single channel as a field of study.The conservation of mass, momentum and energy equations are solved with the method of finite volumes. Numerical simulations are performed using the commercial computer program Ansys Fluent ® CFD (Computational Fluid Dynamics).

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Numerical Study of the Transition Toward Chaos of Two-Dimensional Natural Convection within a Square Cavity

Numerical Heat Transfer Part A Applications ◽

10.1080/10407780490454386 ◽

2005 ◽

Vol 48 (2) ◽

pp. 127-147 ◽

Cited By ~ 16

Author(s):

Michel Aimé Randriazanamparany ◽

Abdelaziz Skouta ◽

Michel Daguenet

Keyword(s):

Natural Convection ◽

Numerical Study ◽

Two Dimensional ◽

Square Cavity

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Conjugate Natural Convection in a Square Cavity Heated From Below

Heat Transfer, Volume 2 ◽

10.1115/imece2004-59463 ◽

2004 ◽

Cited By ~ 3

Author(s):

F. Sa´nchez ◽

F. Solorio ◽

Ruben A´vila

Keyword(s):

Steady State ◽

Natural Convection ◽

Velocity Field ◽

Two Dimensional ◽

Square Cavity ◽

Conjugate Natural Convection ◽

Natural Convection Problem ◽

Energy Equations ◽

Volume Method ◽

Lateral Walls

This paper presents numerical results for two-dimensional steady-state natural convection in a square cavity. The upper and lower walls are kept at different constant temperatures, whereas the lateral walls have certain thickness and thermal conductivity and are externally insulated. Under these conditions we deal with a conjugate natural convection problem in which the heat conduction in the lateral walls is coupled with the internal convection. The continuity, momentum and energy equations were solved by using the finite volume method. The results here presented include: (i) the temperature distribution in the lateral walls and in the fluid, (ii) the velocity field, and (iii) the average Nusselt number at the upper and lower walls. It was found that the steady state fluid flow is strongly dependent on the initial temperature condition, when the fluid is initially at rest. The PIV technique allowed us to get some experimental data by measuring the velocity field in a two-dimensional square cavity. A good agreement between numerical and experimental results was found.

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An Investigation of the Effect of interrupted fin arrangements on the Thermal Performance of a Heat Sink under a Free Convection Condition

Wasit Journal of Engineering Sciences ◽

10.31185/ejuow.vol7.iss1.113 ◽

2019 ◽

Vol 7 (1) ◽

pp. 43-53

Author(s):

Abbas Jassem Jubear ◽

Ali Hameed Abd

Keyword(s):

Heat Transfer ◽

Steady State ◽

Natural Convection ◽

Thermal Performance ◽

Heat Sink ◽

Numerical Study ◽

Ansys Fluent ◽

Fluent Software ◽

Steady State Heat ◽

Steady State Heat Transfer

The heat sink with vertically rectangular interrupted fins was investigated numerically in a natural convection field, with steady-state heat transfer. A numerical study has been conducted using ANSYS Fluent software (R16.1) in order to develop a 3-D numerical model. The dimensions of the fins are (305 mm length, 100 mm width, 17 mm height, and 9.5 mm space between fins. The number of fins used on the surface is eight. In this study, the heat input was used as follows: 20, 40, 60, 80, 100, and 120 watts. This study focused on interrupted rectangular fins with a different arrangement and angle of the fins. Results show that the addition of interruption in fins in various arrangements will improve the thermal performance of the heat sink, and through the results, a better interruption rate as an equation can be obtained.

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