Even though the role of damping in rotordynamics has been known for more than half a century, some incorrect statements on the effects of hysteretic damping, particularly in the subcritical range, can be found still in even the most authoritative journals. Although clarified in the 1970s, this issue recently resurfaced with the incorrect statement that hysteretic damping of rotating elements is destabilizing at any speed (even subcritical). The aim of the present paper is to clarify this issue in terms of the practical applications of the theory in an unequivocal way.

Issue Section:
Technical Briefs
Keywords:
damping, rotors, vibrations, rotation, hysteresis
Topics:
Damping, Rotordynamics, Rotors
1.
Den Hartog, J. P., 1934, Mechanical Vibrations, McGraw-Hill, New York.
2.
Dimentberg, M., 1961, Flexural Vibrations of Rotating Shafts, Butterworth, London, England.
3.
Genta G., 1998, Vibration of Structures and Machines, III ed., Springer, New York.
4.
Muszynska
,
A.
,
1986
, “
Whirl and Whip-Rotor/Bearing Stability Problems
,”
ASME J. Vibr. Acoust.
,
110
(
3
), pp.
443
–
462
.
5.
Crandall, S. H., 1995, “Rotordynamics,” Nonlinear Dynamics and Stochastic Mechanics, Kliemann W. and Sri Namachchivaya N., eds., Boca Raton: CRC Press.
6.
Melanson
,
J.
, and
Zu
,
J. W.
,
1998
, “
Free Vibration and Stability Analysis of Internally Damped Rotating Shafts With General Boundary Conditions
,”
ASME J. Vibr. Acoust.
,
120
, pp.
776
–
783
.
7.
Lund
,
J. W.
,
1974
, “
Stability and Damped Critical Speeds of a Flexible Rotor in Fluid Film Bearings
,”
ASME J. Ind.
,
96
, pp.
509
–
517
.
8.
Crandall, S. H., 1986, Private Communication (March 31) in the form of a letter to J. W. Lund, with copy to the Author.
9.
Zorzi
,
E. S.
, and
Nelson
,
H. D.
,
1977
, “
Finite Element Simulation of Rotor-Bearing Systems with Internal Damping
,”
ASME J. Eng. Power
,
99
, pp.
71
–
76
.
10.
Crandall
,
S. H.
,
1970
, “
The Role of Damping in Vibration Theory
,”
J. Sound Vib.
,
11
(
1
), pp.
3
–
18
.
11.
Jeffcott
,
H. H.
,
1919
, “
The Lateral Vibration of Loaded Shafts in the Neighborhood of a Whirling Speed—The Effect of Want of Balance
,”
Philos. Mag.
,
37
(
6
), pp.
304
–
314
.
12.
Ramanujam
,
G.
, and
Bert
,
C. W.
,
1983
, “
Whirling and Stability of Flywheel Systems, Part 1: Derivation of Combined and Lumped Parameter Models; Part II: Comparison of Numerical Results Obtained with Combined and Lumped Parameter Models
,”
J. Sound Vib.
,
88
(
3
), pp.
369
–
420
.
13.
Genta
,
G.
,
Bassani
,
D.
, and
Delprete
,
C.
,
1966
, “
DYNROT: A Finite Element Code for Rotordynamic Analysis Based on Complex Co-ordinates
,”
Eng. Comput.
,
13
(
6
), pp.
86
–
99
.
14.
Genta
,
G.
,
1985
, “
Consistent Matrices in Rotor Dynamics
,”
Meccanica
,
20
, pp.
235
–
248
.
15.
Genta, G., “
On the Stability of Rotating Bladed Arrays,” J. Sound Vib., in press.
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