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Transient thermal behavior of preloaded three-pad foil bearings / Donghyun Lee in Transactions of the ASME . Journal of tribology, Vol. 133 N° 2 (Avril 2011) 

Public ISBD [article]  in Transactions of the ASME . Journal of tribology > Vol. 133 N° 2 (Avril 2011) . - 11 p. Titre : Transient thermal behavior of preloaded three-pad foil bearings : modeling and experiments Type de document : texte imprimé Auteurs : Donghyun Lee, Auteur ; Daejong Kim, Auteur ; Ramesh P. Sadashiva, Auteur Année de publication : 2012 Article en page(s) : 11 p. Note générale : Tribology Langues : Anglais (eng) Mots-clés : Convection  Electric  power  generation  Fuel  cells  Machine  bearings  Rotors  Solar  cells  Stability  Turbomachinery Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Oil-free turbomachinery have emerged as one of the core technologies for the future green power generation systems as stand-alone systems or hybridized with high temperature fuel cells or solar systems. Oil-free technology allows compact, clean, and maintenance-free operation, and foil bearings are at the center of the technology. Since their first commercial applications in the air cycle machines and auxiliary power units in 1970s, significant improvement has been made to the computational models for rotordynamic behavior. However, many technical issues still remain unsolved or poorly understood, and one of them is thermal management. This paper presents transient three-dimensional thermohydrodynamic (3D THD) model of radial foil bearings to predict transient thermal behavior of the bearing-rotor system. The transient model involves transient energy equations applied to all the mechanical structures and gas film. The model was verified through extensive experimental measurements of transient thermal behavior of three-pad foil bearing for various cooling air pressures, external loads, and speeds. The predictions showed very good agreements with the experiments, and also the 3D THD model could predict potential thermal instability observed in the experimental measurements. DEWEY : 621.5 ISSN : 0742-4787 En ligne : http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JOTRE900013 [...] [article] Transient thermal behavior of preloaded three-pad foil bearings : modeling and experiments [texte imprimé] / Donghyun Lee, Auteur ; Daejong Kim, Auteur ; Ramesh P. Sadashiva, Auteur . - 2012 . - 11 p. Tribology Langues : Anglais (eng) in Transactions of the ASME . Journal of tribology > Vol. 133 N° 2 (Avril 2011) . - 11 p. Mots-clés : Convection  Electric  power  generation  Fuel  cells  Machine  bearings  Rotors  Solar  cells  Stability  Turbomachinery Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Oil-free turbomachinery have emerged as one of the core technologies for the future green power generation systems as stand-alone systems or hybridized with high temperature fuel cells or solar systems. Oil-free technology allows compact, clean, and maintenance-free operation, and foil bearings are at the center of the technology. Since their first commercial applications in the air cycle machines and auxiliary power units in 1970s, significant improvement has been made to the computational models for rotordynamic behavior. However, many technical issues still remain unsolved or poorly understood, and one of them is thermal management. This paper presents transient three-dimensional thermohydrodynamic (3D THD) model of radial foil bearings to predict transient thermal behavior of the bearing-rotor system. The transient model involves transient energy equations applied to all the mechanical structures and gas film. The model was verified through extensive experimental measurements of transient thermal behavior of three-pad foil bearing for various cooling air pressures, external loads, and speeds. The predictions showed very good agreements with the experiments, and also the 3D THD model could predict potential thermal instability observed in the experimental measurements. DEWEY : 621.5 ISSN : 0742-4787 En ligne : http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JOTRE900013 [...]