Effectiveness-ntu computation with a mathematical model for cross-flow heat exchangers

Detalhes bibliográficos
Autor(a) principal: Navarro, H. A. [UNESP]
Data de Publicação: 2007
Outros Autores: Cabezas-Gómez, L. C.
Tipo de documento: Artigo
Idioma: eng
Título da fonte: Repositório Institucional da UNESP
Texto Completo: http://dx.doi.org/10.1590/S0104-66322007000400005
http://hdl.handle.net/11449/24969
Resumo: Due to the wide range of design possibilities, simple manufactured, low maintenance and low cost, cross-flow heat exchangers are extensively used in the petroleum, petrochemical, air conditioning, food storage, and others industries. In this paper a mathematical model for cross-flow heat exchangers with complex flow arrangements for determining epsilon -NTU relations is presented. The model is based on the tube element approach, according to which the heat exchanger outlet temperatures are obtained by discretizing the coil along the tube fluid path. In each cross section of the element, tube-side fluid temperature is assumed to be constant because the heat capacity rate ratio C*=Cmin/Cmax tends toward zero in the element. Thus temperature is controlled by effectiveness of a local element corresponding to an evaporator or a condenser-type element. The model is validated through comparison with theoretical algebraic relations for single-pass cross-flow arrangements with one or more rows. Very small relative errors are obtained showing the accuracy of the present model. epsilon -NTU curves for several complex circuit arrangements are presented. The model developed represents a useful research tool for theoretical and experimental studies on heat exchangers performance.
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spelling Effectiveness-ntu computation with a mathematical model for cross-flow heat exchangersEffectivenessNTUHeat exchangersMathematical modelDue to the wide range of design possibilities, simple manufactured, low maintenance and low cost, cross-flow heat exchangers are extensively used in the petroleum, petrochemical, air conditioning, food storage, and others industries. In this paper a mathematical model for cross-flow heat exchangers with complex flow arrangements for determining epsilon -NTU relations is presented. The model is based on the tube element approach, according to which the heat exchanger outlet temperatures are obtained by discretizing the coil along the tube fluid path. In each cross section of the element, tube-side fluid temperature is assumed to be constant because the heat capacity rate ratio C*=Cmin/Cmax tends toward zero in the element. Thus temperature is controlled by effectiveness of a local element corresponding to an evaporator or a condenser-type element. The model is validated through comparison with theoretical algebraic relations for single-pass cross-flow arrangements with one or more rows. Very small relative errors are obtained showing the accuracy of the present model. epsilon -NTU curves for several complex circuit arrangements are presented. The model developed represents a useful research tool for theoretical and experimental studies on heat exchangers performance.UNESP IGCE Matemática Aplicada e ComputaçãoUSP Escola de Engenharia de São Carlos Departamento de Engenharia MecânicaUNESP IGCE Matemática Aplicada e ComputaçãoBrazilian Society of Chemical EngineeringUniversidade Estadual Paulista (Unesp)Universidade de São Paulo (USP)Navarro, H. A. [UNESP]Cabezas-Gómez, L. C.2013-09-30T18:50:47Z2014-05-20T14:16:32Z2013-09-30T18:50:47Z2014-05-20T14:16:32Z2007-12-01info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/article509-521application/pdfhttp://dx.doi.org/10.1590/S0104-66322007000400005Brazilian Journal of Chemical Engineering. Brazilian Society of Chemical Engineering, v. 24, n. 4, p. 509-521, 2007.0104-6632http://hdl.handle.net/11449/2496910.1590/S0104-66322007000400005S0104-66322007000400005S0104-66322007000400005.pdfSciELOreponame:Repositório Institucional da UNESPinstname:Universidade Estadual Paulista (UNESP)instacron:UNESPengBrazilian Journal of Chemical Engineering0.9250,395info:eu-repo/semantics/openAccess2023-11-09T06:11:29Zoai:repositorio.unesp.br:11449/24969Repositório InstitucionalPUBhttp://repositorio.unesp.br/oai/requestopendoar:29462024-08-05T17:14:36.826323Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP)false
dc.title.none.fl_str_mv Effectiveness-ntu computation with a mathematical model for cross-flow heat exchangers
title Effectiveness-ntu computation with a mathematical model for cross-flow heat exchangers
spellingShingle Effectiveness-ntu computation with a mathematical model for cross-flow heat exchangers
Navarro, H. A. [UNESP]
Effectiveness
NTU
Heat exchangers
Mathematical model
title_short Effectiveness-ntu computation with a mathematical model for cross-flow heat exchangers
title_full Effectiveness-ntu computation with a mathematical model for cross-flow heat exchangers
title_fullStr Effectiveness-ntu computation with a mathematical model for cross-flow heat exchangers
title_full_unstemmed Effectiveness-ntu computation with a mathematical model for cross-flow heat exchangers
title_sort Effectiveness-ntu computation with a mathematical model for cross-flow heat exchangers
author Navarro, H. A. [UNESP]
author_facet Navarro, H. A. [UNESP]
Cabezas-Gómez, L. C.
author_role author
author2 Cabezas-Gómez, L. C.
author2_role author
dc.contributor.none.fl_str_mv Universidade Estadual Paulista (Unesp)
Universidade de São Paulo (USP)
dc.contributor.author.fl_str_mv Navarro, H. A. [UNESP]
Cabezas-Gómez, L. C.
dc.subject.por.fl_str_mv Effectiveness
NTU
Heat exchangers
Mathematical model
topic Effectiveness
NTU
Heat exchangers
Mathematical model
description Due to the wide range of design possibilities, simple manufactured, low maintenance and low cost, cross-flow heat exchangers are extensively used in the petroleum, petrochemical, air conditioning, food storage, and others industries. In this paper a mathematical model for cross-flow heat exchangers with complex flow arrangements for determining epsilon -NTU relations is presented. The model is based on the tube element approach, according to which the heat exchanger outlet temperatures are obtained by discretizing the coil along the tube fluid path. In each cross section of the element, tube-side fluid temperature is assumed to be constant because the heat capacity rate ratio C*=Cmin/Cmax tends toward zero in the element. Thus temperature is controlled by effectiveness of a local element corresponding to an evaporator or a condenser-type element. The model is validated through comparison with theoretical algebraic relations for single-pass cross-flow arrangements with one or more rows. Very small relative errors are obtained showing the accuracy of the present model. epsilon -NTU curves for several complex circuit arrangements are presented. The model developed represents a useful research tool for theoretical and experimental studies on heat exchangers performance.
publishDate 2007
dc.date.none.fl_str_mv 2007-12-01
2013-09-30T18:50:47Z
2013-09-30T18:50:47Z
2014-05-20T14:16:32Z
2014-05-20T14:16:32Z
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/10.1590/S0104-66322007000400005
Brazilian Journal of Chemical Engineering. Brazilian Society of Chemical Engineering, v. 24, n. 4, p. 509-521, 2007.
0104-6632
http://hdl.handle.net/11449/24969
10.1590/S0104-66322007000400005
S0104-66322007000400005
S0104-66322007000400005.pdf
url http://dx.doi.org/10.1590/S0104-66322007000400005
http://hdl.handle.net/11449/24969
identifier_str_mv Brazilian Journal of Chemical Engineering. Brazilian Society of Chemical Engineering, v. 24, n. 4, p. 509-521, 2007.
0104-6632
10.1590/S0104-66322007000400005
S0104-66322007000400005
S0104-66322007000400005.pdf
dc.language.iso.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv Brazilian Journal of Chemical Engineering
0.925
0,395
dc.rights.driver.fl_str_mv info:eu-repo/semantics/openAccess
eu_rights_str_mv openAccess
dc.format.none.fl_str_mv 509-521
application/pdf
dc.publisher.none.fl_str_mv Brazilian Society of Chemical Engineering
publisher.none.fl_str_mv Brazilian Society of Chemical Engineering
dc.source.none.fl_str_mv SciELO
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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