AN INTERFEROMETRIC INVESTIGATION OF NATURAL CONVECTION IN A PARTIALLY OPENED ENCLOSURE WITH A DISCRETE HEAT SOURCE

A numerical study has been conducted for the heat transfer from a discrete heat source by natural convection in air above coupled with conduction dominated melting of a phase change material (PCM) below via a wall of finite thermal diffusivity. Results indicate that the presence of a PCM layer underneath the wall significantly delays the temperature rise of the heat source. The time delay increases as the thermal diffusivity of the wail material decreases and as the thickness of the PCM layer increases. For high thermal conductivity wall materials [Formula: see text] the steady state heat source temperatures are similar and independent of the PCM layer. On the other hand, for [Formula: see text], the steady state temperatures are higher and dependent on the thickness of the PCM layer. A correlation is proposed in terms of the thickness of the PCM layer and the thermal conductivity ratio of the wall.

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A numerical solution for natural convection in an inclined porous cavity with a discrete heat source on one wall

International Journal of Heat and Mass Transfer ◽

10.1016/0017-9310(94)90362-x ◽

1994 ◽

Vol 37 (15) ◽

pp. 2193-2201 ◽

Cited By ~ 14

Author(s):

Shih-Wen Hsiao ◽

Cha'o-Kuang Chen ◽

P. Cheng

Keyword(s):

Natural Convection ◽

Heat Source ◽

Numerical Solution ◽

Porous Cavity ◽

Discrete Heat Source

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Combined Natural Convection–Conduction and Radiation Heat Transfer in a Discretely Heated Open Cavity

Journal of Heat Transfer ◽

10.1115/1.2824068 ◽

1996 ◽

Vol 118 (1) ◽

pp. 56-64 ◽

Cited By ~ 81

Author(s):

A. A. Dehghan ◽

M. Behnia

Keyword(s):

Heat Transfer ◽

Natural Convection ◽

Heat Source ◽

Radiation Heat Transfer ◽

Local Heat Transfer ◽

Local Heat ◽

Radiation Heat ◽

Transfer Coefficients ◽

Thermal Fields ◽

Discrete Heat Source

Combined natural convection, conduction, and radiation heat transfer in an open-top upright cavity containing a discrete heat source has been modeled numerically. The surface emissivity has been varied and its effects on the flow and thermal fields have been determined for different values of Rayleigh number. The complex interaction of the three modes of heat transfer mechanisms is explored by solving the coupled convection, conduction, and radiation equations. It is noted that the inclusion of radiation has a significant effect on the flow, resulting in the formation of a recirculation zone within the cavity. Comparison of the local heat transfer coefficients for the conjugate analysis and no radiation case reveals that the inclusion of radiation has a negligible effect on the heat transfer performance of the heat source. However, comparison of the numerical results with experimental observations shows that accurate prediction of the flow and thermal fields is strongly dependent on the consideration of radiation heat transfer in the numerical case.

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