KEYWORDS

Bump Foil Stiffness

ABOUT THE STIFFNESS OF BUMPS IN AERODYNAMIC FOIL BEARINGS

The bump foils of aerodynamic foil bearings are modeled since long as a foundation with an almost constant stiffness. The stiffness of a single, isolated bump is described by an analytical equation that was obtained from the curved beam theory. The only difference is made between the stiffness of the bump with one fixed end and the bump with both ends free. Comparisons of these analytical stiffness formulas with numerical results generally obtained with commercial codes showed non-negligible differences. Sophisticated models in agreement with numerical simulations were therefore proposed but the difference between the long time existing analytic formulas and the elaborated models of bump stiffness were never explained. The present work explains this difference and introduces new analytical formulas for the single bump stiffness in agreement with numerical simulations.

AUTHORS

Mihai Arghir, Institut PPRIME, Université de Poitiers, Futuroscope, Chasseneuil, France