Mechanical face seals are constitutive components of much larger turbomachines and require consideration of the system dynamics for successful design. The dynamic interplay between the seal and rotor is intensified by recent trends toward reduced clearances, higher speeds, and more flexible rotors. Here, the “rotor” consists of the flexible shaft and the rotating seal seat. The objective here is to, for the first time, determine how the rotor affects the seal performance and vice versa. Thresholds can then be established beyond which the rotor influences the seal but not vice versa (i.e., the rotordynamics can be sent to the seal analysis as an exogenous input). To this end, a model of a flexibly mounted stator face seal is provided including the coupled dynamics of the flexible rotor. The model accounts for axial and angular deflections of the rotor and seal. Coupled rotordynamics are modeled using a lumped-parameter approach including static and dynamic rotor angular misalignments. For expediency, linearized expressions for fluid forces are used, and the resulting steady-state equations of motion are solved analytically to investigate how rotor inertia, speed, and angular misalignment influence the coupled seal dynamics. Importantly, results from the study reveal that in some operating regimes, neglecting the rotordynamics implies healthy seal operation when instead intermittent rub exists between the faces. This work also shows that when the rotor inertia is much larger than the seal inertia, the rotordynamics can be solved separately and used in the seal model as an external input.

References

References
1.
Steinetz
,
B. M.
,
Hendricks
,
R. C.
, and
Munson
,
J.
,
1998
, “
Advanced Seal Technology Role in Meeting Next Generation Turbine Engine Goals
,”
NASA
, Lewis Research Center, Cleveland, OH, Technical Report No.
20000020798
.
2.
Chupp
,
R. E.
,
Hendricks
,
R. C.
,
Lattime
,
S. B.
, and
Steinetz
,
B. M.
,
2006
, “
Sealing in Turbomachinery
,” NASA, Glenn Research Center, Cleveland, OH, Technical Report No.
2006-214341
.
3.
Green
,
I.
, and
Etsion
,
I.
,
1983
, “
Fluid Film Dynamic Coefficients in Mechanical Face Seals
,”
ASME J. Lubr. Technol.
,
105
(
2
), pp.
297
302
.
4.
Green
,
I.
, and
Etsion
,
I.
,
1986
, “
Nonlinear Dynamic Analysis of Noncontacting Coned-Face Mechanical Seals
,”
ASLE Trans.
,
29
(
3
), pp.
383
393
.
5.
Green
,
I.
,
1990
, “
Gyroscopic and Damping Effects on the Stability of a Noncontacting Flexibly-Mounted Rotor Mechanical Face Seal
,”
Dynamics of Rotating Machinery
, Hemisphere, Carlsbad, CA, pp.
153
157
.
6.
Etsion
,
I.
, and
Constantinescu
,
I.
,
1984
, “
Experimental Observation of the Dynamic Behavior of Noncontacting Coned-Face Mechanical Seals
,”
ASLE Trans.
,
27
(
3
), pp.
263
270
.
7.
Lee
,
A. S.
, and
Green
,
I.
,
1995
, “
An Experimental Investigation of the Steady-State Response of a Noncontacting Flexibly Mounted Rotor Mechanical Face Seal
,”
ASME J. Tribol.
,
117
(
1
), pp.
153
159
.
8.
Varney
,
P.
, and
Green
,
I.
,
2016
, “
Impact Phenomena in a Non Contacting Mechanical Face Seal
,”
ASME J. Tribol.
, 139(2), p. 022201.
9.
Etsion
,
I.
, and
Halperin
,
G.
,
2002
, “
A Laser Surface Textured Hydrostatic Mechanical Seal
,”
Tribol. Trans.
,
45
(
3
), pp.
430
434
.
10.
Green
,
I.
,
2002
, “
A Transient Dynamic Analysis of Mechanical Seals Including Asperity Contact and Face Deformation
,”
Tribol. Trans.
,
45
(
3
), pp.
284
293
.
11.
Lee
,
A. S.
, and
Green
,
I.
,
1994
, “
Rotordynamics of a Mechanical Face Seal Riding on a Flexible Shaft
,”
ASME J. Tribol.
,
116
(
2
), pp.
345
351
.
12.
Wileman
,
J.
, and
Green
,
I.
,
1991
, “
The Rotordynamic Coefficients of Mechanical Seals Having Two Flexibly Mounted Rotors
,”
ASME J. Tribol.
,
113
(
4
), pp.
795
804
.
13.
Wileman
,
J.
, and
Green
,
I.
,
1997
, “
Steady-State Analysis of Mechanical Seals With Two Flexibly Mounted Rotors
,”
ASME J. Tribol.
,
119
(
1
), pp.
200
204
.
14.
Wileman
,
J.
, and
Green
,
I.
,
1999
, “
Parametric Investigation of the Steady-State Response of a Mechanical Seal With Two Flexibly Mounted Rotors
,”
ASME J. Tribol.
,
121
(
1
), pp.
69
76
.
15.
Wileman
,
J.
, and
Green
,
I.
,
1996
, “
The Rotor Dynamic Coefficients of Eccentric Mechanical Face Seals
,”
ASME J. Tribol.
,
118
(
1
), pp.
215
224
.
16.
Wileman
,
J.
,
2004
, “
Dynamic Response of Eccentric Face Seals to Synchronous Shaft Whirl
,”
ASME J. Tribol.
,
126
(
2
), pp.
301
309
.
17.
Green
,
I.
,
2008
, “
On the Kinematics and Kinetics of Mechanical Seals, Rotors, and Wobbling Bodies
,”
Mech. Mach. Theory
,
43
(
7
), pp.
909
917
.
18.
Green
,
I.
, and
Etsion
,
I.
,
1986
, “
Pressure and Squeeze Effects on the Dynamic Characteristics of Elastomer O-Rings Under Small Reciprocating Motion
,”
ASME J. Tribol.
,
108
(
3
), pp.
439
444
.
19.
Green
,
I.
, and
Casey
,
C.
,
2005
, “
Crack Detection in a Rotor Dynamic System by Vibration Monitoring—Part I: Analysis
,”
ASME J. Eng. Gas Turbines Power
,
127
(
2
), pp.
425
436
.
20.
Varney
,
P.
, and
Green
,
I.
,
2012
, “
Crack Detection in a Rotor Dynamic System by Vibration Monitoring—Part II: Extended Analysis and Experimental Results
,”
ASME J. Eng. Gas Turbines Power
,
134
(
11
), p.
112501
.
21.
Etsion
,
I.
,
1982
, “
Dynamic Analysis of Noncontacting Face Seals
,”
ASME J. Tribol.
,
104
(
4
), pp.
460
468
.
22.
Etsion
,
I.
,
1980
, “
Squeeze Effects in Radial Face Seals
,”
ASME J. Lubr. Technol.
,
102
(
2
), pp.
145
151
.
23.
Etsion
,
I.
, and
Sharoni
,
A.
,
1980
, “
Performance of End-Face Seals With Diametral Tilt and Coning—Hydrostatic Effects
,”
ASLE Trans.
,
23
(
3
), pp.
279
288
.
24.
Sharoni
,
A.
, and
Etsion
,
I.
,
1981
, “
Performance of End-Face Seals With Diametral Tilt and Coning—Hydrodynamic Effects
,”
ASLE Trans.
,
24
(
1
), pp.
61
70
.
25.
Green
,
I.
,
1987
, “
The Rotor Dynamic Coefficients of Coned-Face Mechanical Seals With Inward or Outward Flow
,”
ASME J. Tribol.
,
109
(
1
), pp.
129
135
.
26.
Green
,
I.
,
1989
, “
Gyroscopic and Support Effects on the Steady-State Response of a Noncontacting Flexibly Mounted Rotor Mechanical Face Seal
,”
ASME J. Tribol.
,
111
(
2
), pp.
200
208
.
27.
Green
,
I.
, and
Etsion
,
I.
,
1986
, “
A Kinematic Model for Mechanical Seals With Antirotation Locks or Positive Drive Devices
,”
ASME J. Tribol.
,
108
(
1
), pp.
42
45
.
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