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Dynamic characteristics of aerostatic porous journal bearings with a surface-restricted layer / Yuta Otsu in Transactions of the ASME . Journal of tribology, Vol. 133 N° 1 (Janvier 2011) 

Public ISBD [article]  in Transactions of the ASME . Journal of tribology > Vol. 133 N° 1 (Janvier 2011) . - 10 p. Titre : Dynamic characteristics of aerostatic porous journal bearings with a surface-restricted layer Type de document : texte imprimé Auteurs : Yuta Otsu, Auteur ; Masaaki Miyatake, Auteur ; Shigeka Yoshimoto, Auteur Année de publication : 2012 Article en page(s) : 10 p. Note générale : Tribology Langues : Anglais (eng) Mots-clés : Damping  Elastic  constants  Graphite  Machine  bearings  Permeability  Porous  materials Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Aerostatic porous bearings have been successfully applied to various precision devices such as machine tools and measuring equipment to achieve a higher accuracy of motion. However, aerostatic porous bearings have a disadvantage in that they are prone to cause pneumatic hammer instability. Therefore, to avoid this instability, a surface-restricted layer that has permeability smaller than the bulk of the porous material is usually formed on the bearing surface. In this paper, the dynamic characteristics of aerostatic porous journal bearings that have a surface-restricted layer are investigated numerically and experimentally. The effects of permeability in bulk porous materials and of a surface-restricted layer on the bearing characteristics are discussed using two kinds of porous material: graphite and metal. It was confirmed that aerostatic porous metal bearings with relatively large permeability could achieve large values of dynamic stiffness and damping coefficients using a low permeability, surface-restricted layer. DEWEY : 621.5 ISSN : 0742-4787 En ligne : http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JOTRE900013 [...] [article] Dynamic characteristics of aerostatic porous journal bearings with a surface-restricted layer [texte imprimé] / Yuta Otsu, Auteur ; Masaaki Miyatake, Auteur ; Shigeka Yoshimoto, Auteur . - 2012 . - 10 p. Tribology Langues : Anglais (eng) in Transactions of the ASME . Journal of tribology > Vol. 133 N° 1 (Janvier 2011) . - 10 p. Mots-clés : Damping  Elastic  constants  Graphite  Machine  bearings  Permeability  Porous  materials Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Aerostatic porous bearings have been successfully applied to various precision devices such as machine tools and measuring equipment to achieve a higher accuracy of motion. However, aerostatic porous bearings have a disadvantage in that they are prone to cause pneumatic hammer instability. Therefore, to avoid this instability, a surface-restricted layer that has permeability smaller than the bulk of the porous material is usually formed on the bearing surface. In this paper, the dynamic characteristics of aerostatic porous journal bearings that have a surface-restricted layer are investigated numerically and experimentally. The effects of permeability in bulk porous materials and of a surface-restricted layer on the bearing characteristics are discussed using two kinds of porous material: graphite and metal. It was confirmed that aerostatic porous metal bearings with relatively large permeability could achieve large values of dynamic stiffness and damping coefficients using a low permeability, surface-restricted layer. DEWEY : 621.5 ISSN : 0742-4787 En ligne : http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JOTRE900013 [...]