A finite element perturbation approach to the prediction of foil bearing stiffness and damping coefficients is presented. The fluid lubricant is modeled as a simple barotropic fluid which is described by the Reynolds equation. The structural model includes membrane, bending, and elastic foundation effects in a general geometry. The equivalent viscous damping of the Coulomb friction caused by the foil relative motion is included in the structural calculation. Bearing stiffness and damping coefficients are predicted for an air-lubricated foil bearing with a corrugated sub-foil. The effects of the bearing number, bearing compliance, sub-foil Coulomb friction, and foil membrane stiffness on the bearing dynamic coefficients are discussed.

Issue Section:
Research Papers
Topics:
Finite element analysis, Foil bearings, Rotors, Bearings, Damping, Stiffness, Coulombs, Fluids, Friction, Membranes, Geometry, Lubricants
1.
Barnum
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, and
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,
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A Theoretical Study of the Dynamic Behavior of Foil Bearings
,”
ASME JOURNAL OF LUBRICATION TECHNOLOGY
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93
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142
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2.
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3.
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, and
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,
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a, “
Effects of Membrane Stresses in the Prediction of Foil Bearing Performance
,”
STLE Tribology Transactions
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4.
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,”
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,”
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6.
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,
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,
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,”
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8.
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,
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, “
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,”
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,”
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10.
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,
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,”
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11.
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,”
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,
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,”
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15.
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16.
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,
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