Prediction and Characterization of Dry-out Heat Flux in Micropillar Wick Structures

Thin-film evaporation in wick structures for cooling high-performance electronic devices is attractive because it harnesses the latent heat of vaporization and does not require external pumping. However, optimizing the wick structures to increase the dry-out heat flux is challenging due to the compl...

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Bibliographic Details
Main Authors: Zhang, Tiejun (Author), Wang, Evelyn (Contributor), Zhu, Yangying (Contributor), Antao, Dion Savio (Contributor), Lu, Zhengmao (Contributor), Somasundaram, Sivanand (Contributor)
Other Authors: Massachusetts Institute of Technology. Department of Mechanical Engineering (Contributor), Singapore-MIT Alliance in Research and Technology (SMART) (Contributor), Wang, Evelyn N. (Contributor)
Format: Article
Language:English
Published: American Chemical Society (ACS), 2017-04-11T12:51:03Z.
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Online Access:Get fulltext
LEADER 02817 am a22003133u 4500
001 108034
042 |a dc 
100 1 0 |a Zhang, Tiejun  |e author 
100 1 0 |a Massachusetts Institute of Technology. Department of Mechanical Engineering  |e contributor 
100 1 0 |a Singapore-MIT Alliance in Research and Technology   |q  (SMART)   |e contributor 
100 1 0 |a Wang, Evelyn N.  |e contributor 
100 1 0 |a Wang, Evelyn  |e contributor 
100 1 0 |a Zhu, Yangying  |e contributor 
100 1 0 |a Antao, Dion Savio  |e contributor 
100 1 0 |a Lu, Zhengmao  |e contributor 
100 1 0 |a Somasundaram, Sivanand  |e contributor 
700 1 0 |a Wang, Evelyn  |e author 
700 1 0 |a Zhu, Yangying  |e author 
700 1 0 |a Antao, Dion Savio  |e author 
700 1 0 |a Lu, Zhengmao  |e author 
700 1 0 |a Somasundaram, Sivanand  |e author 
245 0 0 |a Prediction and Characterization of Dry-out Heat Flux in Micropillar Wick Structures 
260 |b American Chemical Society (ACS),   |c 2017-04-11T12:51:03Z. 
856 |z Get fulltext  |u http://hdl.handle.net/1721.1/108034 
520 |a Thin-film evaporation in wick structures for cooling high-performance electronic devices is attractive because it harnesses the latent heat of vaporization and does not require external pumping. However, optimizing the wick structures to increase the dry-out heat flux is challenging due to the complexities in modeling the liquid-vapor interface and the flow through the wick structures. In this work, we developed a model for thin-film evaporation from micropillar array wick structures and validated the model with experiments. The model numerically simulates liquid velocity, pressure, and meniscus curvature along the wicking direction by conservation of mass, momentum, and energy based on a finite volume approach. Specifically, the three-dimensional meniscus shape, which varies along the wicking direction with the local liquid pressure, is accurately captured by a force balance using the Young-Laplace equation. The dry-out condition is determined when the minimum contact angle on the pillar surface reaches the receding contact angle as the applied heat flux increases. With this model, we predict the dry-out heat flux on various micropillar structure geometries (diameter, pitch, and height) in the length scale range of 1-100 μm and discuss the optimal geometries to maximize the dry-out heat flux. We also performed detailed experiments to validate the model predictions, which show good agreement. This work provides insights into the role of surface structures in thin-film evaporation and offers important design guidelines for enhanced thermal management of high-performance electronic devices. 
520 |a United States. Office of Naval Research (N00014-15-1-2483) 
546 |a en_US 
655 7 |a Article 
773 |t Langmuir