Self-Acting Foil Bearings of Infinite Width

E. J. Barlow

doi:10.1115/1.3616987

Self-Acting Foil Bearings of Infinite Width

Journal of Lubrication Technology ◽

10.1115/1.3616987 ◽

1967 ◽

Vol 89 (3) ◽

pp. 341-345 ◽

Cited By ~ 8

Author(s):

E. J. Barlow

Keyword(s):

Rotating Cylinder ◽

Rigid Cylinder ◽

Cylinder Radius ◽

Foil Bearings ◽

Wrap Angle

In this report, the minimum gap between a rigid cylinder and a moving foil (or between a rotating cylinder and a stationary foil) is determined as a function of the wrap angle as well as of the foil speed and tension, the cylinder radius, and the viscosity of the lubricant.

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Preliminary Experiments With Foil Bearings

Journal of Basic Engineering ◽

10.1115/1.3645803 ◽

1966 ◽

Vol 88 (1) ◽

pp. 1-3 ◽

Cited By ~ 3

Author(s):

L. Licht

Keyword(s):

Rotating Cylinder ◽

Air Gap ◽

Exit Region ◽

Foil Bearings ◽

Capacitive Probe ◽

Experimental Values

A capacitive probe, coincident with the surface of a revolving drum, scans the air gap between a flexible foil and the rotating cylinder. Preliminary measurements of foil displacement are made and compared with results obtained by other investigators. The experiments confirm the existence of an undulating, and sometimes unstable foil configuration in the exit region. A comparison is made between theoretical and experimental values of local amplitude and wavelength of the undulation. The effect of side leakage on displacement is demonstrated.

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An Experimental Study of Elastohydrodynamic Lubrication of Foil Bearings: Part 1—Displacement in the Central Zone

Journal of Lubrication Technology ◽

10.1115/1.3601537 ◽

1968 ◽

Vol 90 (1) ◽

pp. 199-220 ◽

Cited By ~ 24

Author(s):

L. Licht

Keyword(s):

Central Zone ◽

Elastohydrodynamic Lubrication ◽

Rotating Cylinder ◽

Air Gap ◽

Finite Width ◽

Transition Zones ◽

Foil Bearings ◽

Foil Bearing ◽

Theoretical Predictions ◽

Gap Width

An elastic foil under tension is wrapped partly around a rotating cylinder and is supported on a thin film of air. Capacitance probes, coincident with the surface of the cylinder, scan the air gap along the arc of wrap. The cylinder can be traversed across the width of the stationary foil, so that the topography of the air gap can be determined from a series of circumferential scans. Experimental results are compared quantitatively with theoretical predictions for the perfectly flexible and for the elastic foil bearing of infinite width [8, 12]. A comparison is also made with theory, for the case when the angle of wrap is small and the entrance and exit transition zones merge [9]. The effect of foil and gap width on side leakage is illustrated. The last part of this study deals with elastic foil bearings of finite width and with the characteristic “edge effect” in particular. The influence of various parameters on the nature of the displacement field of foils is demonstrated and related to recent analyses [13].

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Theoretical Analysis of Externally Pressurized Porous Foil Bearings—Part I: In the Case of Smooth Surface Porous Shaft

Journal of Tribology ◽

10.1115/1.2830583 ◽

1995 ◽

Vol 117 (1) ◽

pp. 103-111 ◽

Cited By ~ 7

Author(s):

H. Hashimoto

Keyword(s):

Theoretical Analysis ◽

Film Thickness ◽

Reynolds Equation ◽

Numerical Solutions ◽

Computation Time ◽

Hybrid Performance ◽

Foil Bearings ◽

Wide Range ◽

Wrap Angle ◽

Element Technique

In this paper, the theoretical analysis for the hybrid performance of externally pressurized foil bearings with a hollow porous shaft is described. In the analysis, in order to save computation time and to improve the convergency of solutions, the two-dimensional modified Reynolds equation considering the added flow through hollow porous shaft is reduced to the ordinary differential equation by expanding the film pressure to the Fourier series with respect to the axial coordinate. The reduced Reynolds equation and the equilibrium equation for the perfectly flexible foil are solved iteratively by the finite element technique. The numerical solutions for the pressure and film thickness distributions between the foil and the shaft are obtained for a wide range of bearing width-to-diameter ratio under the various combinations of dimensionless supply pressure, dimensionless permeability of porous shaft and dimensionless wrap angle of foil, and the hybrid performance of foil bearings are examined theoretically. It is found from the numerical results that the bearing width has the significant effect on the pressure and film thickness distributions between the foil and the shaft.

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