Abstract
Tilting-pad journal bearings are often used in high performance machinery operating at speeds above the first critical speed, in order to improve bearing stability. In many cases such machinery may still be prone to subsynchronous or unstable vibration problems. The influence of the dynamic characteristics of the tilting-pad bearings on the response of the complete rotor system is therefore of great importance. This paper is primarily concerned with the damping provided by such bearings. A number of factors are considered including frequency dependence of the dynamic coefficients, influence of pad support flexibility, and a simple method for evaluation of effective damping required to maintain rotor stability.
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Abbreviations
- B:
-
Cross coupling stiffness
- C:
-
Damping
- Ci:
-
Bearing damping
- Cp:
-
Pad clearance (Rp - R)
- Cs:
-
Damping to maintain stability
- D:
-
Journal diameter
- E:
-
Modulus of elasticity
- I:
-
Moment of area/pad inertia
- k:
-
Pad stiffness
- K:
-
Stiffness
- ω:
-
Rotational speed (rad/s)
- Kp:
-
Pivot stiffness
- F:
-
Force
- m:
-
Mass
- N:
-
Rotational speed (Hz)
- R:
-
Journal radius
- Rp:
-
Pad radius
- W:
-
Load
- δ:
-
Pad rotation angle Dynamic viscosity
- ωn :
-
Critical speed (rad/s)
References
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© 1992 Springer-Verlag London Limited
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White, M.F. (1992). A Consideration of Damping in Rotors Supported by Tilting-Pad Bearings. In: Goodwin, M.J. (eds) Rotordynamics ’92. Springer, London. https://doi.org/10.1007/978-1-4471-1979-1_50
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DOI: https://doi.org/10.1007/978-1-4471-1979-1_50
Publisher Name: Springer, London
Print ISBN: 978-3-540-19754-6
Online ISBN: 978-1-4471-1979-1
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