Convective Heat Transfer in Graphite Foam Heat Sinks With Baffle and Stagger Structures

K. C. Leong, Hongyu Li, L. W. Jin, J. C. Chai

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

Highly conductive porous media have recently been considered for enhanced cooling applications due to their large internal contact surface area, which promotes convection at the pore level. In this paper, graphite foams that possess high thermal conductivity but low permeability are investigated for convection heat transfer enhancement using air as coolant. Two novel heat sink structures are designed to reduce the fluid pressure drop. Both experimental and numerical approaches are adopted in the study. The experimental data show that the designed structures significantly reduce flow resistance in graphite foams while maintaining relatively good heat removal performance. The numerical results obtained based on the local thermal nonequilibrium model are validated by experimental data and show that the inlet air flow partially penetrates the structured foam walls, while the remaining air flows tortuously through slots in the structure. Flow mixing, which is absent in the block graphite foam, is observed in the freestream area inside the designed structure. It can be concluded that graphite foams with appropriately designed structures can be applied as air-cooled heat sinks in thermal management applications.

LanguageEnglish
Article number060902
Number of pages9
JournalJournal of Heat Transfer
Volume133
Issue number6
Early online date4 Mar 2011
DOIs
Publication statusPublished - Jun 2011
Externally publishedYes

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baffles
Graphite
convective heat transfer
heat sinks
Heat sinks
foams
Foams
graphite
Heat transfer
air flow
convection
Air
flow resistance
Heat convection
fluid pressure
Air intakes
air
coolants
pressure drop
slots

Cite this

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title = "Convective Heat Transfer in Graphite Foam Heat Sinks With Baffle and Stagger Structures",
abstract = "Highly conductive porous media have recently been considered for enhanced cooling applications due to their large internal contact surface area, which promotes convection at the pore level. In this paper, graphite foams that possess high thermal conductivity but low permeability are investigated for convection heat transfer enhancement using air as coolant. Two novel heat sink structures are designed to reduce the fluid pressure drop. Both experimental and numerical approaches are adopted in the study. The experimental data show that the designed structures significantly reduce flow resistance in graphite foams while maintaining relatively good heat removal performance. The numerical results obtained based on the local thermal nonequilibrium model are validated by experimental data and show that the inlet air flow partially penetrates the structured foam walls, while the remaining air flows tortuously through slots in the structure. Flow mixing, which is absent in the block graphite foam, is observed in the freestream area inside the designed structure. It can be concluded that graphite foams with appropriately designed structures can be applied as air-cooled heat sinks in thermal management applications.",
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Convective Heat Transfer in Graphite Foam Heat Sinks With Baffle and Stagger Structures. / Leong, K. C.; Li, Hongyu; Jin, L. W.; Chai, J. C.

In: Journal of Heat Transfer, Vol. 133, No. 6, 060902, 06.2011.

Research output: Contribution to journalArticle

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AU - Leong, K. C.

AU - Li, Hongyu

AU - Jin, L. W.

AU - Chai, J. C.

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KW - forced convection

KW - graphite foam

KW - Nusselt number

KW - porous medium

KW - pressure drop

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