Optimization and thermal characterization of uniform silicon micropillar based evaporators

The development of high power density and compact electronic devices result in the generation of large and concentrated heat loads, which need to be dissipated effectively to avoid electronics failure. Vapor chambers are promising candidates to overcome the thermal management challenges, owing to it...

Full description

Bibliographic Details
Main Authors: Wei, Mengyao, He, Bin, Liang, Qian, Somasundaram, Sivanand, Tan, Chuan Seng, Wang, Evelyn N.
Other Authors: School of Electrical and Electronic Engineering
Format: Journal Article
Language:English
Published: 2020
Subjects:
Online Access:https://hdl.handle.net/10356/145224
_version_ 1826111807230574592
author Wei, Mengyao
He, Bin
Liang, Qian
Somasundaram, Sivanand
Tan, Chuan Seng
Wang, Evelyn N.
author2 School of Electrical and Electronic Engineering
author_facet School of Electrical and Electronic Engineering
Wei, Mengyao
He, Bin
Liang, Qian
Somasundaram, Sivanand
Tan, Chuan Seng
Wang, Evelyn N.
author_sort Wei, Mengyao
collection NTU
description The development of high power density and compact electronic devices result in the generation of large and concentrated heat loads, which need to be dissipated effectively to avoid electronics failure. Vapor chambers are promising candidates to overcome the thermal management challenges, owing to its passive working mechanism and excellent heat removal capability. Micropillar-based evaporators for these vapor chambers allow for high capillary pressure, large permeability and extended evaporation areas, which enhances the critical dryout heat flux of the vapor chamber. However, predictive models that evaluate the performance of micropillar evaporators are limited, where the selection of micropillar geometries is typically based on empirical data and the evaporator temperature rise has not been considered. In this paper, we report a comprehensive and systematic study of cylindrical silicon micropillar-based uniform evaporators. First, we constructed a semi-analytical model to predict the capillary-limited dryout heat flux. We performed an optimization to select the micropillar geometries by considering the evaporator temperature rise. Subsequently, we microfabricated uniform evaporators with various geometries and thermally characterized the evaporators in a controlled vacuum environmental chamber. Then, we validated the model with the experimental results and showed that the model and experiments have reasonable agreement within 20%. The heat transfer coefficients decreased with smaller micropillar diameter/pitch ratios and taller micropillar heights. This work provides comprehensive insights into the design of uniform micropillar-based evaporators and can serve as useful guidelines for advanced vapor chambers and other phase-change devices.
first_indexed 2024-10-01T02:56:32Z
format Journal Article
id ntu-10356/145224
institution Nanyang Technological University
language English
last_indexed 2024-10-01T02:56:32Z
publishDate 2020
record_format dspace
spelling ntu-10356/1452242020-12-15T06:13:19Z Optimization and thermal characterization of uniform silicon micropillar based evaporators Wei, Mengyao He, Bin Liang, Qian Somasundaram, Sivanand Tan, Chuan Seng Wang, Evelyn N. School of Electrical and Electronic Engineering Engineering::Electrical and electronic engineering Evaporators Heat Transfer The development of high power density and compact electronic devices result in the generation of large and concentrated heat loads, which need to be dissipated effectively to avoid electronics failure. Vapor chambers are promising candidates to overcome the thermal management challenges, owing to its passive working mechanism and excellent heat removal capability. Micropillar-based evaporators for these vapor chambers allow for high capillary pressure, large permeability and extended evaporation areas, which enhances the critical dryout heat flux of the vapor chamber. However, predictive models that evaluate the performance of micropillar evaporators are limited, where the selection of micropillar geometries is typically based on empirical data and the evaporator temperature rise has not been considered. In this paper, we report a comprehensive and systematic study of cylindrical silicon micropillar-based uniform evaporators. First, we constructed a semi-analytical model to predict the capillary-limited dryout heat flux. We performed an optimization to select the micropillar geometries by considering the evaporator temperature rise. Subsequently, we microfabricated uniform evaporators with various geometries and thermally characterized the evaporators in a controlled vacuum environmental chamber. Then, we validated the model with the experimental results and showed that the model and experiments have reasonable agreement within 20%. The heat transfer coefficients decreased with smaller micropillar diameter/pitch ratios and taller micropillar heights. This work provides comprehensive insights into the design of uniform micropillar-based evaporators and can serve as useful guidelines for advanced vapor chambers and other phase-change devices. 2020-12-15T06:13:19Z 2020-12-15T06:13:19Z 2018 Journal Article Wei, M., He, B., Liang, Q., Somasundaram, S., Tan, C. S., & Wang, E. N. (2018). Optimization and thermal characterization of uniform silicon micropillar based evaporators. International Journal of Heat and Mass Transfer, 127, 51-60. doi:10.1016/j.ijheatmasstransfer.2018.06.128 0017-9310 https://hdl.handle.net/10356/145224 10.1016/j.ijheatmasstransfer.2018.06.128 127 51 60 en International Journal of Heat and Mass Transfer © 2018 Elsevier Ltd. All rights reserved.
spellingShingle Engineering::Electrical and electronic engineering
Evaporators
Heat Transfer
Wei, Mengyao
He, Bin
Liang, Qian
Somasundaram, Sivanand
Tan, Chuan Seng
Wang, Evelyn N.
Optimization and thermal characterization of uniform silicon micropillar based evaporators
title Optimization and thermal characterization of uniform silicon micropillar based evaporators
title_full Optimization and thermal characterization of uniform silicon micropillar based evaporators
title_fullStr Optimization and thermal characterization of uniform silicon micropillar based evaporators
title_full_unstemmed Optimization and thermal characterization of uniform silicon micropillar based evaporators
title_short Optimization and thermal characterization of uniform silicon micropillar based evaporators
title_sort optimization and thermal characterization of uniform silicon micropillar based evaporators
topic Engineering::Electrical and electronic engineering
Evaporators
Heat Transfer
url https://hdl.handle.net/10356/145224
work_keys_str_mv AT weimengyao optimizationandthermalcharacterizationofuniformsiliconmicropillarbasedevaporators
AT hebin optimizationandthermalcharacterizationofuniformsiliconmicropillarbasedevaporators
AT liangqian optimizationandthermalcharacterizationofuniformsiliconmicropillarbasedevaporators
AT somasundaramsivanand optimizationandthermalcharacterizationofuniformsiliconmicropillarbasedevaporators
AT tanchuanseng optimizationandthermalcharacterizationofuniformsiliconmicropillarbasedevaporators
AT wangevelynn optimizationandthermalcharacterizationofuniformsiliconmicropillarbasedevaporators