Post on 17-Dec-2018
ABSTRACT
In the present work a numeric study of thermal and fluid dynamics behavior of natural air convection in a bi-dimensional square cavity is presented, in a laminar flow. The square cavity has two walls heated with different temperatures and two isolated walls, the Boussinesq approximation is used and a constant Prandtl number. The Finite Volume Method is used for the discretization of flow equations. The staggered load of variables is adopted and Power-Law and SIMPLE models are used. The numeric simulation is
4 6made up of several Rayleigh numbers, 10 Ra 10 , and the results of average Nusselt numbers are compared to values obtained in the literature. Flow and isotherm lines are presented and analyzed. The numerical results presented here in this work agree with the ones available in the literature and can be used by researchers who work in the convection problem numeric simulation area.
Keywords: natural convection, square cavity, Finite Volume Method
aViviana Cocco Mariani ,band Ivan Moura Belo
a Pontifícia Universidade Católica do Paraná
Departamento de Engenharia Mecânica
Bairro Prado Velho
CP. 81611-970, Curitiba, Paraná, Brasil
viviana.mariani@pucpr.brb Pontifícia Universidade Católica do Paraná
Departamento de Engenharia Mecânica
CP. 81611-970, Curitiba, Paraná, Brasil
ivan.belo@pucpr.br
NUMERICAL STUDIES OF NATURAL CONVECTION IN A SQUARE CAVITY
NuNux
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gHkLpPPrRRaTu, v
U, Vx,y,zX,Y,Z
Engenharia Térmica (Thermal Engineering), Vol. 5 - Nº 01 - July 2006 68
Ciência/Science
)/(;/;/
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Engenharia Térmica (Thermal Engineering), Vol. 5 - Nº 01 - July 2006 69
Ciência/Science Mariani and Belo et al. Numerical Studies of ...
( ) 0=¶¶- XXq
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,10max R -£×Ñ=
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Figure 2. Streamlines (to the left) and isotherms (to the
4right) for Rayleigh = 10
maxy
Nu
4Table 1. Numerical results for Ra = 10 .
Engenharia Térmica (Thermal Engineering), Vol. 5 - Nº 01 - July 2006 70
Ciência/Science Mariani and Belo et al. Numerical Studies of ...
5Table 2. Numerical results for Ra = 10 .
6Table 3. Numerical results for Ra = 10 .
-1.0 -0.5 0.0 0.5 1.0U/Umax
0.0
0.2
0.4
0.6
0.8
1.0
Y
Ra = 104
Ra = 105
Ra = 106
0.0 0.2 0.4 0.6 0.8 1.0X
-1.0
-0.5
0.0
0.5
1.0
V/V
max
Ra = 104
Ra = 105
Ra = 106
Engenharia Térmica (Thermal Engineering), Vol. 5 - Nº 01 - July 2006 71
Ciência/Science Mariani and Belo et al. Numerical Studies of ...