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Numerical analysis on dynamic coefficients of self-acting gas-lubricated tilting-pad journal bearings / Yang Lihua in Transactions of the ASME . Journal of tribology, Vol. 130 N°1 (Janvier 2008) 

Public ISBD [article]  in Transactions of the ASME . Journal of tribology > Vol. 130 N°1 (Janvier 2008) . - 11 p. Titre : Numerical analysis on dynamic coefficients of self-acting gas-lubricated tilting-pad journal bearings Type de document : texte imprimé Auteurs : Yang Lihua, Auteur ; Qi Shemiao, Auteur ; Yu Lie, Auteur Année de publication : 2008 Article en page(s) : 11 p. Note générale : Tribology Langues : Anglais (eng) Mots-clés : Bearings  Damping  Numerical  analysis  Gas  bearings  Stiffness  Journal  bearings  Inertia  (Mechanics) Résumé : Although gas-lubricated tilting-pad bearings are widely used in high-speed turbomachinery, the theoretical prediction of the dynamic characteristics of tilting-pad gas bearings is also a very difficult problem because of its structural complexity. Several approaches have been proposed to solve this problem such as the pad assembly method and the small perturbation method. A numerical method by combining the partial derivative method with the equivalent coefficient method is presented in this paper to evaluate the dynamic stiffness and damping coefficients of self-acting tilting-pad gas bearing. The dynamic coefficients with the pads fixed and with the pads perturbation are, respectively, obtained for a typical self-acting tilting-pad gas bearing by using the proposed method to mainly explain the dependency of the bearing dynamic coefficients on the perturbation frequency. For bearings with the pads perturbation, the cross-coupling stiffness and damping coefficients are almost negligible compared with the direct ones. At lower perturbation frequency, the stiffness coefficients increase, while the damping coefficients decrease with an increasing frequency. The higher perturbation frequencies have very little effects on the bearing dynamic coefficients. Dynamic stiffness coefficients approach to the constant and damping coefficients to zero. However, with the pads fixed, in a low range of frequency, the absolute values of cross-coupling stiffness coefficients decrease with frequency. Furthermore, the cross-coupling coefficients are not negligible compared with the direct ones. In addition, the effects of pad inertia on dynamic coefficients are studied and compared with the results of pad inertia neglected. En ligne : http://tribology.asmedigitalcollection.asme.org/article.aspx?articleid=1467966 [article] Numerical analysis on dynamic coefficients of self-acting gas-lubricated tilting-pad journal bearings [texte imprimé] / Yang Lihua, Auteur ; Qi Shemiao, Auteur ; Yu Lie, Auteur . - 2008 . - 11 p. Tribology Langues : Anglais (eng) in Transactions of the ASME . Journal of tribology > Vol. 130 N°1 (Janvier 2008) . - 11 p. Mots-clés : Bearings  Damping  Numerical  analysis  Gas  bearings  Stiffness  Journal  bearings  Inertia  (Mechanics) Résumé : Although gas-lubricated tilting-pad bearings are widely used in high-speed turbomachinery, the theoretical prediction of the dynamic characteristics of tilting-pad gas bearings is also a very difficult problem because of its structural complexity. Several approaches have been proposed to solve this problem such as the pad assembly method and the small perturbation method. A numerical method by combining the partial derivative method with the equivalent coefficient method is presented in this paper to evaluate the dynamic stiffness and damping coefficients of self-acting tilting-pad gas bearing. The dynamic coefficients with the pads fixed and with the pads perturbation are, respectively, obtained for a typical self-acting tilting-pad gas bearing by using the proposed method to mainly explain the dependency of the bearing dynamic coefficients on the perturbation frequency. For bearings with the pads perturbation, the cross-coupling stiffness and damping coefficients are almost negligible compared with the direct ones. At lower perturbation frequency, the stiffness coefficients increase, while the damping coefficients decrease with an increasing frequency. The higher perturbation frequencies have very little effects on the bearing dynamic coefficients. Dynamic stiffness coefficients approach to the constant and damping coefficients to zero. However, with the pads fixed, in a low range of frequency, the absolute values of cross-coupling stiffness coefficients decrease with frequency. Furthermore, the cross-coupling coefficients are not negligible compared with the direct ones. In addition, the effects of pad inertia on dynamic coefficients are studied and compared with the results of pad inertia neglected. En ligne : http://tribology.asmedigitalcollection.asme.org/article.aspx?articleid=1467966