A flexible carbon nanotube-pyrolytic carbon sandwich paper with a stable structure and high heat-dissipation capacity

Plasma electrolytic oxidation (PEO) coating was obtained on AZ31 Mg alloy using a direct current in a sodium silicate-based electrolyte with and without a carbon nanotube (CNT) additive. The surface morphology and phase composition of the PEO coatings were investigated through field emission scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The corrosion-resistance properties of the PEO coatings were evaluated using potentiodynamic polarization measurements and electrochemical impedance spectroscopy (EIS) in a 3.5 wt.% NaCl solution. Furthermore, the heat-dissipation property was evaluated by a heat-flux measurement setup using a modified steady-state method and Fourier transform infrared spectroscopy (FT-IR). The results demonstrate that, by increasing the concentration of CNT additive in the electrolyte, the micropores and cracks of the PEO coatings are greatly decreased. In addition, the anticorrosion performance of the PEO coatings that incorporated CNT for the protection of the Mg substrate was improved. Finally, the coating’s heat-dissipation property was improved by the incorporation of CNT with high thermal conductivity and high thermal emissivity.

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Experimental Investigation of a Thermosyphon With Microstructure on the Boiling Surface

Journal of Thermal Science and Engineering Applications ◽

10.1115/1.4041442 ◽

2018 ◽

Vol 11 (1) ◽

Author(s):

Y. Chai ◽

W. Tian ◽

J. Tian ◽

L. W. Jin ◽

X. Z. Meng ◽

...

Keyword(s):

Heat Transfer ◽

Heat Dissipation ◽

Pool Boiling ◽

High Heat ◽

Primary Concern ◽

Heat Transfer Efficiency ◽

Heater Wall ◽

Micro Structures ◽

Thermal Physical Properties ◽

Graphite Foam

Abstract In recent years, a primary concern in the development of electronic technology is high heat dissipation of power devices. The advantages of unique thermal physical properties of graphite foam raise up the possibility of developing pool boiling system with better heat transfer efficiency. A compact thermosyphon was developed with graphite foam insertions to explore how different parameters affect boiling performance. Heater wall temperature, superheat, departure frequency of bubbles, and thermal resistance of the system were analyzed. The results indicated that the boiling performance is affected significantly by thermal conductivity and pore diameter of graphite foam. A proposed heat transfer empirical correlation reflecting the relations between graphite foam micro structures and pool boiling performance of Novec7100 was developed in this paper.

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Evaporation-enhanced, dynamically-adaptive air (gas)-cooled heat sink for thermal management of high heat dissipation devices

2008 11th Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems ◽

10.1109/itherm.2008.4544288 ◽

2008 ◽

Author(s):

Andrei G. Fedorov ◽

J. Mark Meacham

Keyword(s):

Thermal Management ◽

Heat Sink ◽

Heat Dissipation ◽

High Heat

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Microstructured Ceramic-Coated Carbon Nanotube Surfaces for High Heat Flux Pool Boiling

ACS Applied Nano Materials ◽

10.1021/acsanm.9b01116 ◽

2019 ◽

Vol 2 (9) ◽

pp. 5538-5545 ◽

Cited By ~ 1

Author(s):

Hangbo Zhao ◽

Susmita Dash ◽

Navdeep Singh Dhillon ◽

Sanha Kim ◽

Bethany Lettiere ◽

...

Keyword(s):

Heat Flux ◽

Carbon Nanotube ◽

Pool Boiling ◽

High Heat ◽

High Heat Flux ◽

Coated Carbon

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Heat Dissipation Mechanism at Carbon Nanotube Junctions on Silicon Oxide Substrate

Journal of Heat Transfer ◽

10.1115/1.4025436 ◽

2014 ◽

Vol 136 (5) ◽

Cited By ~ 6

Author(s):

Liang Chen ◽

Satish Kumar

Keyword(s):

Carbon Nanotube ◽

Heat Dissipation ◽

Silicon Oxide ◽

Low Frequency ◽

Intermediate Frequency ◽

Oxide System ◽

Carbon Nanotube Junctions ◽

Oxide Substrate ◽

Efficient Coupling ◽

Dynamics Simulations

This study investigates heat dissipation at carbon nanotube (CNT) junctions supported on silicon dioxide substrate using molecular dynamics simulations. The temperature rise in a CNT (∼top CNT) not making direct contact with the oxide substrate but only supported by other CNTs (∼bottom CNT) is observed to be hundreds of degree higher compared with the CNTs well-contacted with the substrate at similar power densities. The analysis of spectral temperature decay of CNT-oxide system shows very fast intratube energy transfer in a CNT from high-frequency band to intermediate-frequency bands. The low frequency phonon band (0–5 THz) of top CNT shows two-stage energy relaxation which results from the efficient coupling of low frequency phonons in the CNT-oxide system and the blocking of direct transport of high- and intermediate-frequency phonons of top CNT to the oxide substrate by bottom CNT.

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PTFE Modification to Enhance Boiling Performance of Porous Surface

Journal of Heat Transfer ◽

10.1115/1.4047262 ◽

2020 ◽

Vol 142 (7) ◽

Author(s):

Ya-Qiao Wang ◽

Jia-Li Luo ◽

Yi Heng ◽

Dong-Chuan Mo ◽

Shu-Shen Lyu

Keyword(s):

Boiling Heat Transfer ◽

Heat Dissipation ◽

Flat Surface ◽

Hydrophobic Surface ◽

High Heat ◽

High Heat Flux ◽

Pin Fin ◽

Original Surface ◽

Wall Superheat ◽

Hybrid Modification

Abstract Boiling heat transfer is one of the most effective methods to meet the challenge of heat dissipation of high heat flux devices. A wetting hybrid surface has been shown to have better performance than the hydrophilic or hydrophobic surface. This kind of wetting hybrid modification is always carried out on a plain or flat surface. In this paper, polytetrafluoroethylene (PTFE) powders were coated on a superhydrophilic microcopper dendrite fin surface to build a wetting hybrid surface. The pool-boiling experimental results showed that after applying the coating, the wall superheat dramatically decreased to 8 K, which is 9 K lower than that on the original surface at 250 W·cm−2, and has a better performance than a silicon pin-fin-based wetting hybrid surface.

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