Documents disponibles écrits par cet auteur

Air-side heat-transfer enhancement by a new winglet-type vortex generator array in a plain-fin round-tube heat exchanger / J. He in Journal of heat transfer, Vol. 132 N° 7 (Juillet 2010) 

Public ISBD [article]  in Journal of heat transfer > Vol. 132 N° 7 (Juillet 2010) . - pp. [071801-1/9] Titre : Air-side heat-transfer enhancement by a new winglet-type vortex generator array in a plain-fin round-tube heat exchanger Type de document : texte imprimé Auteurs : J. He, Auteur ; L. Liu, Auteur ; A. M. Jacobi, Auteur Article en page(s) : pp. [071801-1/9] Note générale : Physique Langues : Anglais (eng) Mots-clés : Heat  exchanger  Fin-and-tube  V  formation  Vortex  generator  Winglet  array Index. décimale : 536 Chaleur. Thermodynamique Résumé : The impact of a vortex-generation technique for air-side heat-transfer improvement is experimentally investigated through full-scale wind-tunnel testing of a plain-fin round-tube heat exchanger under dry-surface conditions. Inspired by the formation locomotion of animals in nature, a new vortex generator (VG) array deployed in a “V” is proposed in the present work, aiming to create constructive interference between vortices. The array is composed of two delta-winglet pairs and placed at an attack angle of 10 deg or 30 deg. Its effectiveness is compared with a baseline configuration and two conventional single-pair designs placed at 30 deg, a small pair with half the area of the array and a large pair with the same area as the array. The frontal air velocity considered ranges from 2.3 m/s to 5.5 m/s, corresponding to a Reynolds number range based on the hydraulic diameter of 1400–3400. The experimental results show little impact of the 10 deg array and a moderate heat-transfer improvement of up to 32% for the small pair, both introducing additional pressure loss of approximately 20–40%. For the 30 deg array and the large pair, similar augmentation of 25–55% in air-side heat-transfer coefficient is obtained accompanied by average pressure drop penalties of 90% and 140%, respectively. Performance evaluation using the criteria of the modified area goodness factor and the volume goodness factor indicates the superiority of the heat exchanger enhanced by the 30 deg array among all the investigated VGs. The VG array is found more effective at comparatively low Reynolds numbers, representative of many heating, ventilation, air-conditioning, and refrigeration applications and compact heat-exchanger designs. DEWEY : 536 ISSN : 0022-1481 En ligne : http://asmedl.aip.org/vsearch/servlet/VerityServlet?KEY=JHTRAO&ONLINE=YES&smode= [...] [article] Air-side heat-transfer enhancement by a new winglet-type vortex generator array in a plain-fin round-tube heat exchanger [texte imprimé] / J. He, Auteur ; L. Liu, Auteur ; A. M. Jacobi, Auteur . - pp. [071801-1/9]. Physique Langues : Anglais (eng) in Journal of heat transfer > Vol. 132 N° 7 (Juillet 2010) . - pp. [071801-1/9] Mots-clés : Heat  exchanger  Fin-and-tube  V  formation  Vortex  generator  Winglet  array Index. décimale : 536 Chaleur. Thermodynamique Résumé : The impact of a vortex-generation technique for air-side heat-transfer improvement is experimentally investigated through full-scale wind-tunnel testing of a plain-fin round-tube heat exchanger under dry-surface conditions. Inspired by the formation locomotion of animals in nature, a new vortex generator (VG) array deployed in a “V” is proposed in the present work, aiming to create constructive interference between vortices. The array is composed of two delta-winglet pairs and placed at an attack angle of 10 deg or 30 deg. Its effectiveness is compared with a baseline configuration and two conventional single-pair designs placed at 30 deg, a small pair with half the area of the array and a large pair with the same area as the array. The frontal air velocity considered ranges from 2.3 m/s to 5.5 m/s, corresponding to a Reynolds number range based on the hydraulic diameter of 1400–3400. The experimental results show little impact of the 10 deg array and a moderate heat-transfer improvement of up to 32% for the small pair, both introducing additional pressure loss of approximately 20–40%. For the 30 deg array and the large pair, similar augmentation of 25–55% in air-side heat-transfer coefficient is obtained accompanied by average pressure drop penalties of 90% and 140%, respectively. Performance evaluation using the criteria of the modified area goodness factor and the volume goodness factor indicates the superiority of the heat exchanger enhanced by the 30 deg array among all the investigated VGs. The VG array is found more effective at comparatively low Reynolds numbers, representative of many heating, ventilation, air-conditioning, and refrigeration applications and compact heat-exchanger designs. DEWEY : 536 ISSN : 0022-1481 En ligne : http://asmedl.aip.org/vsearch/servlet/VerityServlet?KEY=JHTRAO&ONLINE=YES&smode= [...]

A model for predicting the thermal-hydraulic performance of louvered-fin, flat-tube heat exchangers under frosting conditions / Y. Xia in International journal of refrigeration, Vol. 33 N° 2 (Mars 2010) 

Public ISBD [article]  in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 321-333 Titre : A model for predicting the thermal-hydraulic performance of louvered-fin, flat-tube heat exchangers under frosting conditions Titre original : Un modèle pour la prévision de la performance thermohydraulique d'échangeurs de chaleur à ailettes à persienne à tubes plats sous des conditions de givrage Type de document : texte imprimé Auteurs : Y. Xia, Auteur ; A. M. Jacobi, Auteur Année de publication : 2011 Article en page(s) : pp. 321-333 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Heat  exchanger  Finned  tube  Louvered  fin  Geometry  Modeling  Performance  Frosting Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Correlations and a model are developed to predict the time-varying performance of folded-louvered-fin, microchannel heat exchangers. The model utilizes the correlations developed from the experimental data and incorporates a sub-model for frost properties. The model successfully predicts the heat transfer performance of the heat exchangers studied, but its ability to predict the pressure-drop behavior needs further improvement. The model can be used to evaluate geometry effects on the frosting behavior of the louvered-fin, microchannel heat exchangers, and can be easily generalized to other applications with simultaneous heat and mass transfer. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002357 [article] A model for predicting the thermal-hydraulic performance of louvered-fin, flat-tube heat exchangers under frosting conditions = Un modèle pour la prévision de la performance thermohydraulique d'échangeurs de chaleur à ailettes à persienne à tubes plats sous des conditions de givrage [texte imprimé] / Y. Xia, Auteur ; A. M. Jacobi, Auteur . - 2011 . - pp. 321-333. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 321-333 Mots-clés : Heat  exchanger  Finned  tube  Louvered  fin  Geometry  Modeling  Performance  Frosting Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Correlations and a model are developed to predict the time-varying performance of folded-louvered-fin, microchannel heat exchangers. The model utilizes the correlations developed from the experimental data and incorporates a sub-model for frost properties. The model successfully predicts the heat transfer performance of the heat exchangers studied, but its ability to predict the pressure-drop behavior needs further improvement. The model can be used to evaluate geometry effects on the frosting behavior of the louvered-fin, microchannel heat exchangers, and can be easily generalized to other applications with simultaneous heat and mass transfer. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002357

Wetting, frost formation and melt water retention pattern on microgrooved surfaces / Rahman, M. A. in Journal of heat transfer, Vol. 134 N° 8 (special issue) (Août 2012) 

Public ISBD [article]  in Journal of heat transfer > Vol. 134 N° 8 (special issue) (Août 2012) . - 01 p. Titre : Wetting, frost formation and melt water retention pattern on microgrooved surfaces Type de document : texte imprimé Auteurs : Rahman, M. A., Auteur ; A. M. Jacobi, Auteur Année de publication : 2012 Article en page(s) : 01 p. Note générale : heat transfer Langues : Anglais (eng) Note de contenu : Photogallery DEWEY : 536 ISSN : 0022-1481 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JHTRAO000134000008 [...] [article] Wetting, frost formation and melt water retention pattern on microgrooved surfaces [texte imprimé] / Rahman, M. A., Auteur ; A. M. Jacobi, Auteur . - 2012 . - 01 p. heat transfer Langues : Anglais (eng) in Journal of heat transfer > Vol. 134 N° 8 (special issue) (Août 2012) . - 01 p. Note de contenu : Photogallery DEWEY : 536 ISSN : 0022-1481 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JHTRAO000134000008 [...]

X-ray micro-computed tomography imaging of open-cell metal foams / J. J. Bock in Journal of heat transfer, Vol. 134 N° 8 (special issue) (Août 2012) 

Public ISBD [article]  in Journal of heat transfer > Vol. 134 N° 8 (special issue) (Août 2012) . - 01 p. Titre : X-ray micro-computed tomography imaging of open-cell metal foams Type de document : texte imprimé Auteurs : J. J. Bock, Auteur ; A. M. Jacobi, Auteur Année de publication : 2012 Article en page(s) : 01 p. Note générale : heat transfer Langues : Anglais (eng) Note de contenu : Photogallery DEWEY : 536 ISSN : 0022-1481 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JHTRAO000134000008 [...] [article] X-ray micro-computed tomography imaging of open-cell metal foams [texte imprimé] / J. J. Bock, Auteur ; A. M. Jacobi, Auteur . - 2012 . - 01 p. heat transfer Langues : Anglais (eng) in Journal of heat transfer > Vol. 134 N° 8 (special issue) (Août 2012) . - 01 p. Note de contenu : Photogallery DEWEY : 536 ISSN : 0022-1481 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JHTRAO000134000008 [...]