A critical assessment on evaporative cooling performance of micro finned micro gap for high heat flux applications

Micro gap heat sinks reduce flow boiling instabilities and generate more uniform surface temperature than typical microchannels. Heat transfer rate in micro gaps can be increased by providing micro fins. Micro fins increase surface area as well as generate turbulence, which disturbs the laminar sub-...

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Main Authors: Ahmed, Shugata, Ismail, Ahmad Faris, Sulaeman, Erwin, Hasan, Muhammad Hasibul
Format: Conference or Workshop Item
Language:English
English
Published: 2015
Subjects:
Online Access:http://irep.iium.edu.my/46468/
http://irep.iium.edu.my/46468/
http://irep.iium.edu.my/46468/1/A_CRITICAL_ASSESSMENT_ON_EVAPORATIVE_COOLING_PERFORMANCE_OF_MICRO_FINNED_MICRO_GAP_FOR_HIGH_HEAT_FLUX_APPLICATIONS_%282%29.pdf
http://irep.iium.edu.my/46468/4/46468.pdf
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recordtype eprints
spelling iium-464682016-07-16T18:49:40Z http://irep.iium.edu.my/46468/ A critical assessment on evaporative cooling performance of micro finned micro gap for high heat flux applications Ahmed, Shugata Ismail, Ahmad Faris Sulaeman, Erwin Hasan, Muhammad Hasibul TJ Mechanical engineering and machinery Micro gap heat sinks reduce flow boiling instabilities and generate more uniform surface temperature than typical microchannels. Heat transfer rate in micro gaps can be increased by providing micro fins. Micro fins increase surface area as well as generate turbulence, which disturbs the laminar sub-layer. Hence, heat transfer rate enhances due to rapid fluid mixing. In this paper, effectiveness of flow boiling in a micro finned micro gap for cooling purpose has been investigated numerically. Flow boiling of pure water in the heat sink has been simulated using FLUENT 14.5 release. From results, it has been observed that upper and lower solid-fluid interfaces show different thermal behaviors with heat flux increment. Area-weighted average heat transfer coefficient of upper surface increases with increasing heat flux, while decreases for lower surface. In a net effect, thermal resistance of the heat sink increases with heat flux increment after onset of boiling for low Reynolds number. However, for high Reynolds number, thermal resistance changes slowly with heat flux variation. Pressure drop penalty has been found high for high heat fluxes during boiling. Interestingly, increment of pumping power is not always cost effective as thermal resistance does not decrease sharply all over the range. Hence, it is suggested that optimized pumping power should be used for highest efficiency. Keywords: Micro fin, Micro gap, Flow boiling, Thermal resistance and Pumping power 2015 Conference or Workshop Item NonPeerReviewed application/pdf en http://irep.iium.edu.my/46468/1/A_CRITICAL_ASSESSMENT_ON_EVAPORATIVE_COOLING_PERFORMANCE_OF_MICRO_FINNED_MICRO_GAP_FOR_HIGH_HEAT_FLUX_APPLICATIONS_%282%29.pdf application/pdf en http://irep.iium.edu.my/46468/4/46468.pdf Ahmed, Shugata and Ismail, Ahmad Faris and Sulaeman, Erwin and Hasan, Muhammad Hasibul (2015) A critical assessment on evaporative cooling performance of micro finned micro gap for high heat flux applications. In: International Postgraduate Conference on Engineering Research (IPCER) 2015 , 27th-28th Oct. 2015, Gombak Campus, IIUM. (Unpublished) http://www.iium.edu.my/ipcer/15/index.php/parallel-session
repository_type Digital Repository
institution_category Local University
institution International Islamic University Malaysia
building IIUM Repository
collection Online Access
language English
English
topic TJ Mechanical engineering and machinery
spellingShingle TJ Mechanical engineering and machinery
Ahmed, Shugata
Ismail, Ahmad Faris
Sulaeman, Erwin
Hasan, Muhammad Hasibul
A critical assessment on evaporative cooling performance of micro finned micro gap for high heat flux applications
description Micro gap heat sinks reduce flow boiling instabilities and generate more uniform surface temperature than typical microchannels. Heat transfer rate in micro gaps can be increased by providing micro fins. Micro fins increase surface area as well as generate turbulence, which disturbs the laminar sub-layer. Hence, heat transfer rate enhances due to rapid fluid mixing. In this paper, effectiveness of flow boiling in a micro finned micro gap for cooling purpose has been investigated numerically. Flow boiling of pure water in the heat sink has been simulated using FLUENT 14.5 release. From results, it has been observed that upper and lower solid-fluid interfaces show different thermal behaviors with heat flux increment. Area-weighted average heat transfer coefficient of upper surface increases with increasing heat flux, while decreases for lower surface. In a net effect, thermal resistance of the heat sink increases with heat flux increment after onset of boiling for low Reynolds number. However, for high Reynolds number, thermal resistance changes slowly with heat flux variation. Pressure drop penalty has been found high for high heat fluxes during boiling. Interestingly, increment of pumping power is not always cost effective as thermal resistance does not decrease sharply all over the range. Hence, it is suggested that optimized pumping power should be used for highest efficiency. Keywords: Micro fin, Micro gap, Flow boiling, Thermal resistance and Pumping power
format Conference or Workshop Item
author Ahmed, Shugata
Ismail, Ahmad Faris
Sulaeman, Erwin
Hasan, Muhammad Hasibul
author_facet Ahmed, Shugata
Ismail, Ahmad Faris
Sulaeman, Erwin
Hasan, Muhammad Hasibul
author_sort Ahmed, Shugata
title A critical assessment on evaporative cooling performance of micro finned micro gap for high heat flux applications
title_short A critical assessment on evaporative cooling performance of micro finned micro gap for high heat flux applications
title_full A critical assessment on evaporative cooling performance of micro finned micro gap for high heat flux applications
title_fullStr A critical assessment on evaporative cooling performance of micro finned micro gap for high heat flux applications
title_full_unstemmed A critical assessment on evaporative cooling performance of micro finned micro gap for high heat flux applications
title_sort critical assessment on evaporative cooling performance of micro finned micro gap for high heat flux applications
publishDate 2015
url http://irep.iium.edu.my/46468/
http://irep.iium.edu.my/46468/
http://irep.iium.edu.my/46468/1/A_CRITICAL_ASSESSMENT_ON_EVAPORATIVE_COOLING_PERFORMANCE_OF_MICRO_FINNED_MICRO_GAP_FOR_HIGH_HEAT_FLUX_APPLICATIONS_%282%29.pdf
http://irep.iium.edu.my/46468/4/46468.pdf
first_indexed 2023-09-18T21:06:10Z
last_indexed 2023-09-18T21:06:10Z
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