Effect of microfin surfaces on boiling heat transfer using HFE-7100 as working fluid

Detalhes bibliográficos
Autor(a) principal: Kiyomura, Igor Seicho [UNESP]
Data de Publicação: 2020
Outros Autores: Nunes, Jéssica Martha [UNESP], de Souza, Reinaldo Rodrigues [UNESP], Gajghate, Sameer S., Bhaumik, Swapan, Cardoso, Elaine Maria [UNESP]
Tipo de documento: Artigo
Idioma: eng
Título da fonte: Repositório Institucional da UNESP
Texto Completo: http://dx.doi.org/10.1007/s40430-020-02439-7
http://hdl.handle.net/11449/198967
Resumo: One promising way to enhance the heat transfer coefficient (HTC) and the critical heat flux (CHF) is modifying the heating surface morphology by using machining techniques, coating, and chemical processes. Microstructured surfaces, i.e., surfaces with the presence of micropillars on the surface, provide small perturbations in the liquid, affecting the vapor bubbles dynamic. These structures increase the heating surface area and change the fluid flow. Microfins can have different shapes and sizes and can be arranged in different patterns to improve heat transfer. This study aims to evaluate experimentally the thermal performance of different microfin surfaces by using HFE-7100 as working fluid. Square micro-pillar arrays were etched on a plain copper surface through the micro-milling process. Square microfins of different length scales (i.e., height and side length) were uniformly spaced on the plain copper surface. The inter-fin space had the same value, 250 μm, for all surfaces in order to control the effective roughness, Reff, defined as the ratio of the area in contact with the liquid to the projected area. Microfin surfaces intensify the HTC as compared to plain surfaces and the number of fins is the main factor for the HTC enhancement; if the number of microfins is constant, the larger the effective roughness, the higher the heat transfer performance. Additionally, the capillary-wicking ability increases and it also improves the HTC and the dryout heat flux due to the prevention of hotspots in the microfin surface. Thus, the surface thermal behavior is a function of the surface morphology and its surface capillary wicking.
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spelling Effect of microfin surfaces on boiling heat transfer using HFE-7100 as working fluidEffective roughnessHeat transfer coefficientHFE-7100MicropillarsPool boilingOne promising way to enhance the heat transfer coefficient (HTC) and the critical heat flux (CHF) is modifying the heating surface morphology by using machining techniques, coating, and chemical processes. Microstructured surfaces, i.e., surfaces with the presence of micropillars on the surface, provide small perturbations in the liquid, affecting the vapor bubbles dynamic. These structures increase the heating surface area and change the fluid flow. Microfins can have different shapes and sizes and can be arranged in different patterns to improve heat transfer. This study aims to evaluate experimentally the thermal performance of different microfin surfaces by using HFE-7100 as working fluid. Square micro-pillar arrays were etched on a plain copper surface through the micro-milling process. Square microfins of different length scales (i.e., height and side length) were uniformly spaced on the plain copper surface. The inter-fin space had the same value, 250 μm, for all surfaces in order to control the effective roughness, Reff, defined as the ratio of the area in contact with the liquid to the projected area. Microfin surfaces intensify the HTC as compared to plain surfaces and the number of fins is the main factor for the HTC enhancement; if the number of microfins is constant, the larger the effective roughness, the higher the heat transfer performance. Additionally, the capillary-wicking ability increases and it also improves the HTC and the dryout heat flux due to the prevention of hotspots in the microfin surface. Thus, the surface thermal behavior is a function of the surface morphology and its surface capillary wicking.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)School of Engineering Post-Graduation Program in Mechanical Engineering UNESP - São Paulo State University, Av. Brasil, 56UNESP - São Paulo State University, Campus of São João da Boa VistaMechanical Engineering Department National Institute of Technology AgartalaSchool of Engineering Post-Graduation Program in Mechanical Engineering UNESP - São Paulo State University, Av. Brasil, 56UNESP - São Paulo State University, Campus of São João da Boa VistaFAPESP: 2013/15431-7FAPESP: 2017/13813-0FAPESP: 2019/02566-8CNPq: 458702/2014-5Universidade Estadual Paulista (Unesp)National Institute of Technology AgartalaKiyomura, Igor Seicho [UNESP]Nunes, Jéssica Martha [UNESP]de Souza, Reinaldo Rodrigues [UNESP]Gajghate, Sameer S.Bhaumik, SwapanCardoso, Elaine Maria [UNESP]2020-12-12T01:27:00Z2020-12-12T01:27:00Z2020-07-01info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articlehttp://dx.doi.org/10.1007/s40430-020-02439-7Journal of the Brazilian Society of Mechanical Sciences and Engineering, v. 42, n. 7, 2020.1806-36911678-5878http://hdl.handle.net/11449/19896710.1007/s40430-020-02439-72-s2.0-85086315799Scopusreponame:Repositório Institucional da UNESPinstname:Universidade Estadual Paulista (UNESP)instacron:UNESPengJournal of the Brazilian Society of Mechanical Sciences and Engineeringinfo:eu-repo/semantics/openAccess2021-10-22T21:16:10Zoai:repositorio.unesp.br:11449/198967Repositório InstitucionalPUBhttp://repositorio.unesp.br/oai/requestopendoar:29462024-08-05T21:00:10.844501Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP)false
dc.title.none.fl_str_mv Effect of microfin surfaces on boiling heat transfer using HFE-7100 as working fluid
title Effect of microfin surfaces on boiling heat transfer using HFE-7100 as working fluid
spellingShingle Effect of microfin surfaces on boiling heat transfer using HFE-7100 as working fluid
Kiyomura, Igor Seicho [UNESP]
Effective roughness
Heat transfer coefficient
HFE-7100
Micropillars
Pool boiling
title_short Effect of microfin surfaces on boiling heat transfer using HFE-7100 as working fluid
title_full Effect of microfin surfaces on boiling heat transfer using HFE-7100 as working fluid
title_fullStr Effect of microfin surfaces on boiling heat transfer using HFE-7100 as working fluid
title_full_unstemmed Effect of microfin surfaces on boiling heat transfer using HFE-7100 as working fluid
title_sort Effect of microfin surfaces on boiling heat transfer using HFE-7100 as working fluid
author Kiyomura, Igor Seicho [UNESP]
author_facet Kiyomura, Igor Seicho [UNESP]
Nunes, Jéssica Martha [UNESP]
de Souza, Reinaldo Rodrigues [UNESP]
Gajghate, Sameer S.
Bhaumik, Swapan
Cardoso, Elaine Maria [UNESP]
author_role author
author2 Nunes, Jéssica Martha [UNESP]
de Souza, Reinaldo Rodrigues [UNESP]
Gajghate, Sameer S.
Bhaumik, Swapan
Cardoso, Elaine Maria [UNESP]
author2_role author
author
author
author
author
dc.contributor.none.fl_str_mv Universidade Estadual Paulista (Unesp)
National Institute of Technology Agartala
dc.contributor.author.fl_str_mv Kiyomura, Igor Seicho [UNESP]
Nunes, Jéssica Martha [UNESP]
de Souza, Reinaldo Rodrigues [UNESP]
Gajghate, Sameer S.
Bhaumik, Swapan
Cardoso, Elaine Maria [UNESP]
dc.subject.por.fl_str_mv Effective roughness
Heat transfer coefficient
HFE-7100
Micropillars
Pool boiling
topic Effective roughness
Heat transfer coefficient
HFE-7100
Micropillars
Pool boiling
description One promising way to enhance the heat transfer coefficient (HTC) and the critical heat flux (CHF) is modifying the heating surface morphology by using machining techniques, coating, and chemical processes. Microstructured surfaces, i.e., surfaces with the presence of micropillars on the surface, provide small perturbations in the liquid, affecting the vapor bubbles dynamic. These structures increase the heating surface area and change the fluid flow. Microfins can have different shapes and sizes and can be arranged in different patterns to improve heat transfer. This study aims to evaluate experimentally the thermal performance of different microfin surfaces by using HFE-7100 as working fluid. Square micro-pillar arrays were etched on a plain copper surface through the micro-milling process. Square microfins of different length scales (i.e., height and side length) were uniformly spaced on the plain copper surface. The inter-fin space had the same value, 250 μm, for all surfaces in order to control the effective roughness, Reff, defined as the ratio of the area in contact with the liquid to the projected area. Microfin surfaces intensify the HTC as compared to plain surfaces and the number of fins is the main factor for the HTC enhancement; if the number of microfins is constant, the larger the effective roughness, the higher the heat transfer performance. Additionally, the capillary-wicking ability increases and it also improves the HTC and the dryout heat flux due to the prevention of hotspots in the microfin surface. Thus, the surface thermal behavior is a function of the surface morphology and its surface capillary wicking.
publishDate 2020
dc.date.none.fl_str_mv 2020-12-12T01:27:00Z
2020-12-12T01:27:00Z
2020-07-01
dc.type.status.fl_str_mv info:eu-repo/semantics/publishedVersion
dc.type.driver.fl_str_mv info:eu-repo/semantics/article
format article
status_str publishedVersion
dc.identifier.uri.fl_str_mv http://dx.doi.org/10.1007/s40430-020-02439-7
Journal of the Brazilian Society of Mechanical Sciences and Engineering, v. 42, n. 7, 2020.
1806-3691
1678-5878
http://hdl.handle.net/11449/198967
10.1007/s40430-020-02439-7
2-s2.0-85086315799
url http://dx.doi.org/10.1007/s40430-020-02439-7
http://hdl.handle.net/11449/198967
identifier_str_mv Journal of the Brazilian Society of Mechanical Sciences and Engineering, v. 42, n. 7, 2020.
1806-3691
1678-5878
10.1007/s40430-020-02439-7
2-s2.0-85086315799
dc.language.iso.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv Journal of the Brazilian Society of Mechanical Sciences and Engineering
dc.rights.driver.fl_str_mv info:eu-repo/semantics/openAccess
eu_rights_str_mv openAccess
dc.source.none.fl_str_mv Scopus
reponame:Repositório Institucional da UNESP
instname:Universidade Estadual Paulista (UNESP)
instacron:UNESP
instname_str Universidade Estadual Paulista (UNESP)
instacron_str UNESP
institution UNESP
reponame_str Repositório Institucional da UNESP
collection Repositório Institucional da UNESP
repository.name.fl_str_mv Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP)
repository.mail.fl_str_mv
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