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Modeling of heat transfer in microchannel gas flow / Tomasz Lewandowski in Journal of heat transfer, Vol. 133 N° 2 (Fevrier 2011) 

Public ISBD [article]  in Journal of heat transfer > Vol. 133 N° 2 (Fevrier 2011) . - pp. [022401/1-15] Titre : Modeling of heat transfer in microchannel gas flow Type de document : texte imprimé Auteurs : Tomasz Lewandowski, Auteur ; Tomasz Ochrymiuk, Auteur ; Justyna Czerwinska, Auteur Année de publication : 2011 Article en page(s) : pp. [022401/1-15] Note générale : Physique Langues : Anglais (eng) Mots-clés : Microchannel  gas  flow  Heat  transfer  Slip  regime  Turbomachinery Index. décimale : 536 Chaleur. Thermodynamique Résumé : Due to the existence of a velocity slip and temperature jump on the solid walls, the heat transfer in microchannels significantly differs from the one in the macroscale. In our research, we have focused on the pressure driven gas flows in a simple finite microchannel geometry, with an entrance and an outlet, for low Reynolds (Re<200) and low Knudsen (Kn<0.01) numbers. For such a regime, the slip induced phenomena are strongly connected with the viscous effects. As a result, heat transfer is also significantly altered. For the optimization of flow conditions, we have investigated various temperature gradient configurations, additionally changing Reynolds and Knudsen numbers. The entrance effects, slip flow, and temperature jump lead to complex relations between flow behavior and heat transfer. We have shown that slip effects are generally insignificant for flow behavior. However, two configuration setups (hot wall cold gas and cold wall hot gas) are affected by slip in distinguishably different ways. For the first one, which concerns turbomachinery, the mass flow rate can increase by about 1% in relation to the no-slip case, depending on the wall-gas temperature difference. Heat transfer is more significantly altered. The Nusselt number between slip and no-slip cases at the outlet of the microchannel is increased by about 10%. DEWEY : 536 ISSN : 0022-1481 En ligne : http://asmedl.aip.org/vsearch/servlet/VerityServlet?KEY=JHTRAO&ONLINE=YES&smode= [...] [article] Modeling of heat transfer in microchannel gas flow [texte imprimé] / Tomasz Lewandowski, Auteur ; Tomasz Ochrymiuk, Auteur ; Justyna Czerwinska, Auteur . - 2011 . - pp. [022401/1-15]. Physique Langues : Anglais (eng) in Journal of heat transfer > Vol. 133 N° 2 (Fevrier 2011) . - pp. [022401/1-15] Mots-clés : Microchannel  gas  flow  Heat  transfer  Slip  regime  Turbomachinery Index. décimale : 536 Chaleur. Thermodynamique Résumé : Due to the existence of a velocity slip and temperature jump on the solid walls, the heat transfer in microchannels significantly differs from the one in the macroscale. In our research, we have focused on the pressure driven gas flows in a simple finite microchannel geometry, with an entrance and an outlet, for low Reynolds (Re<200) and low Knudsen (Kn<0.01) numbers. For such a regime, the slip induced phenomena are strongly connected with the viscous effects. As a result, heat transfer is also significantly altered. For the optimization of flow conditions, we have investigated various temperature gradient configurations, additionally changing Reynolds and Knudsen numbers. The entrance effects, slip flow, and temperature jump lead to complex relations between flow behavior and heat transfer. We have shown that slip effects are generally insignificant for flow behavior. However, two configuration setups (hot wall cold gas and cold wall hot gas) are affected by slip in distinguishably different ways. For the first one, which concerns turbomachinery, the mass flow rate can increase by about 1% in relation to the no-slip case, depending on the wall-gas temperature difference. Heat transfer is more significantly altered. The Nusselt number between slip and no-slip cases at the outlet of the microchannel is increased by about 10%. DEWEY : 536 ISSN : 0022-1481 En ligne : http://asmedl.aip.org/vsearch/servlet/VerityServlet?KEY=JHTRAO&ONLINE=YES&smode= [...]