Thermal behaviour of stirred yoghurt during cooling in plate heat exchangers
Autor(a) principal: | |
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Data de Publicação: | 2006 |
Outros Autores: | , , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
Texto Completo: | http://hdl.handle.net/10198/466 |
Resumo: | In this study, CFD calculations were made in order to analyse the thermal behaviour of yoghurt in a plate heat exchanger, the yoghurt viscosity being described by a Herschel-Bulkley model. The influence of Reynolds number on local Nusselt numbers was analysed as well as the influence of entry effects on average Nusselt number. Numerical runs considering and discarding the influence of temperature on the viscosity were performed and the impact on average Nusselt numbers was analysed. Transversal variations of viscosity were studied and thermal correlations including the ratio between bulk and wall viscosities are proposed. The obtained thermal correlations were compared with the experimental ones (described in the literature) and a very good agreement was found, mainly when considering the effect of temperature on viscosity. Simulations with a non-Newtonian fluid having lower Prandtl numbers than yoghurt were performed in order to analyse the influence of this variation on the Reynolds number exponent of the thermal correlation. |
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Thermal behaviour of stirred yoghurt during cooling in plate heat exchangersStirred yoghurtPlate heat exchangersLocal nusselt numbersComputational rheologyIn this study, CFD calculations were made in order to analyse the thermal behaviour of yoghurt in a plate heat exchanger, the yoghurt viscosity being described by a Herschel-Bulkley model. The influence of Reynolds number on local Nusselt numbers was analysed as well as the influence of entry effects on average Nusselt number. Numerical runs considering and discarding the influence of temperature on the viscosity were performed and the impact on average Nusselt numbers was analysed. Transversal variations of viscosity were studied and thermal correlations including the ratio between bulk and wall viscosities are proposed. The obtained thermal correlations were compared with the experimental ones (described in the literature) and a very good agreement was found, mainly when considering the effect of temperature on viscosity. Simulations with a non-Newtonian fluid having lower Prandtl numbers than yoghurt were performed in order to analyse the influence of this variation on the Reynolds number exponent of the thermal correlation.ElsevierBiblioteca Digital do IPBFernandes, Carla S.Dias, Ricardo P.Nóbrega, João M.Afonso, Isabel M.Melo, Luis F.Maia, João M.2008-02-08T10:45:10Z20062006-01-01T00:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleapplication/pdfhttp://hdl.handle.net/10198/466engFernandes, Carla S.; Dias, Ricardo P.; Nóbrega, João M.; Afonso, Isabel M.; Melo, Luis F.; Maia, João M. (2006). Thermal behaviour of stirred yoghurt during cooling in plate heat exchangers. Journal of Food Engineering. ISSN 0260-8774. 76:3 p.433-4390260-877410.1016/j.jfoodeng.2005.05.043info:eu-repo/semantics/openAccessreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2023-11-21T10:03:24Zoai:bibliotecadigital.ipb.pt:10198/466Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-19T22:54:16.303090Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãofalse |
dc.title.none.fl_str_mv |
Thermal behaviour of stirred yoghurt during cooling in plate heat exchangers |
title |
Thermal behaviour of stirred yoghurt during cooling in plate heat exchangers |
spellingShingle |
Thermal behaviour of stirred yoghurt during cooling in plate heat exchangers Fernandes, Carla S. Stirred yoghurt Plate heat exchangers Local nusselt numbers Computational rheology |
title_short |
Thermal behaviour of stirred yoghurt during cooling in plate heat exchangers |
title_full |
Thermal behaviour of stirred yoghurt during cooling in plate heat exchangers |
title_fullStr |
Thermal behaviour of stirred yoghurt during cooling in plate heat exchangers |
title_full_unstemmed |
Thermal behaviour of stirred yoghurt during cooling in plate heat exchangers |
title_sort |
Thermal behaviour of stirred yoghurt during cooling in plate heat exchangers |
author |
Fernandes, Carla S. |
author_facet |
Fernandes, Carla S. Dias, Ricardo P. Nóbrega, João M. Afonso, Isabel M. Melo, Luis F. Maia, João M. |
author_role |
author |
author2 |
Dias, Ricardo P. Nóbrega, João M. Afonso, Isabel M. Melo, Luis F. Maia, João M. |
author2_role |
author author author author author |
dc.contributor.none.fl_str_mv |
Biblioteca Digital do IPB |
dc.contributor.author.fl_str_mv |
Fernandes, Carla S. Dias, Ricardo P. Nóbrega, João M. Afonso, Isabel M. Melo, Luis F. Maia, João M. |
dc.subject.por.fl_str_mv |
Stirred yoghurt Plate heat exchangers Local nusselt numbers Computational rheology |
topic |
Stirred yoghurt Plate heat exchangers Local nusselt numbers Computational rheology |
description |
In this study, CFD calculations were made in order to analyse the thermal behaviour of yoghurt in a plate heat exchanger, the yoghurt viscosity being described by a Herschel-Bulkley model. The influence of Reynolds number on local Nusselt numbers was analysed as well as the influence of entry effects on average Nusselt number. Numerical runs considering and discarding the influence of temperature on the viscosity were performed and the impact on average Nusselt numbers was analysed. Transversal variations of viscosity were studied and thermal correlations including the ratio between bulk and wall viscosities are proposed. The obtained thermal correlations were compared with the experimental ones (described in the literature) and a very good agreement was found, mainly when considering the effect of temperature on viscosity. Simulations with a non-Newtonian fluid having lower Prandtl numbers than yoghurt were performed in order to analyse the influence of this variation on the Reynolds number exponent of the thermal correlation. |
publishDate |
2006 |
dc.date.none.fl_str_mv |
2006 2006-01-01T00:00:00Z 2008-02-08T10:45:10Z |
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://hdl.handle.net/10198/466 |
url |
http://hdl.handle.net/10198/466 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
Fernandes, Carla S.; Dias, Ricardo P.; Nóbrega, João M.; Afonso, Isabel M.; Melo, Luis F.; Maia, João M. (2006). Thermal behaviour of stirred yoghurt during cooling in plate heat exchangers. Journal of Food Engineering. ISSN 0260-8774. 76:3 p.433-439 0260-8774 10.1016/j.jfoodeng.2005.05.043 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Elsevier |
publisher.none.fl_str_mv |
Elsevier |
dc.source.none.fl_str_mv |
reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação instacron:RCAAP |
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Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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RCAAP |
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RCAAP |
reponame_str |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
repository.name.fl_str_mv |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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1799135140990943232 |