Abstract

Small gas foil bearings (FBs) with shaft diameter below 25 mm can find many applications in air compressors for fuel cells, electrical turbo chargers, small unmanned air vehicles, turbo alternators, etc. These small machines are characterized by very light load to the radial FBs, and thus rotordynamics stability is more challenging than load capacity. However, a main challenge of gas foil thrust bearings (GFTBs) is how to increase the load capacity, and the challenge remains the same regardless of the size. In previous publications on experimental studies on GFTBs, the measured load capacity is well below the prediction due to challenges in testing as well as manufacturing of GFTBs. Difficulty in achieving the design load capacity often leads to increasing the bearing size in actual applications with penalty of higher power loss. This paper presents design feature of a novel GFTB with outer diameter of 38 mm and static performance up to 155 krpm under external load of 75 N using a high-speed test rig. The 38 mm GFTB presented in this paper is a three-layered structure for easy design and manufacturing, and the unique design feature allows easy scale down and scale up to different sizes. Reynolds equations for compressible gas and the two-dimensional thin plate model were adopted for fluid–structure interaction simulation to predict load capacity and power loss of the GFTB. The predicted power loss and load capacity agree well with the measurements.

References

References
1.
Heshmat
,
H.
,
Walowit
,
J. A.
, and
Pinkus
,
O.
,
1983
, “
Analysis of Gas Lubricated Compliant Thrust Bearings
,”
ASME J. Tribol.
,
105
(
4
), pp.
638
646
. 10.1115/1.3254696
2.
Heshmat
,
C.
,
Xu
,
D.
, and
Heshmat
,
H.
,
1999
, “
Analysis of Gas Lubricated Foil Thrust Bearings Using Coupled Finite Element and Finite Difference Methods
,”
ASME J. Tribol.
,
122
(
1
), pp.
199
204
. 10.1115/1.555343
3.
Park
,
D.
,
Kim
,
C.
, and
Jang
,
G.
,
2008
, “
Theoretical Considerations of Static and Dynamic Characteristics of Air Foil Thrust Bearing With Tilt and Slip Flow
,”
Tribol. Int.
,
41
(
4
), pp.
282
295
. 10.1016/j.triboint.2007.08.001
4.
Lee
,
D.
, and
Kim
,
D.
,
2010
, “
Design and Performance Prediction of Hybrid Air Foil Thrust Bearings
,”
ASME J. Eng. Gas Turbines Power
,
133
(
4
), p.
042501
. 10.1115/1.4002249
5.
Lee
,
D.
, and
Kim
,
D.
,
2011
, “
Three-Dimensional Thermohydrodynamic Analyses of Rayleigh Step Air Foil Thrust Bearing With Radially Arranged Bump Foils
,”
Tribol. Trans.
,
54
(
3
), pp.
432
448
. 10.1080/10402004.2011.556314
6.
Xu
,
F.
, and
Kim
,
D.
,
2016
, “
Three-Dimensional Turbulent Thermo-Elastohydrodynamic Analyses of Hybrid Thrust Foil Bearings Using Real Gas Model
,”
Proceedings of the ASME Turbo Expo 2016
,
Seoul, South Korea
,
June 13–17
, p.
V07BT31A030
.
7.
San Andrés
,
L.
,
Ryu
,
K.
, and
Diemer
,
P.
,
2014
, “
Prediction of Gas Thrust Foil Bearing Performance for Oil-Free Automotive Turbochargers
,”
ASME J. Eng. Gas Turbines Power
,
137
(
3
), p.
032502
. 10.1115/1.4028389
8.
Iordanoff
,
I.
,
1999
, “
Analysis of an Aerodynamic Compliant Foil Thrust Bearing: Method for a Rapid Design
,”
ASME J. Tribol.
,
121
(
4
), pp.
816
822
. 10.1115/1.2834140
9.
Dickman
,
J.
,
2010
, “
An Investigation of Gas Foil Thrust Bearing Performance and Its Influencing Factors
,”
MS thesis
,
Case Western Reserve University
,
Cleveland, OH
.
10.
Bauman
,
S.
,
2005
, “
An Oil-Free Thrust Foil Bearing Facility Design, Calibration, and Operation
,”
NASA
,
NASA/TM—2005-213568
.
11.
Dykas
,
B.
,
Bruckner
,
R.
, and
DellaCorte
,
C.
,
2008
, “
Design, Fabrication, and Performance of Foil Gas Thrust Bearings for Microturbomachinery Applications
,”
NASA
,
NASA/TM-2008-215062
.
12.
Stahl
,
B.
,
2012
, “
Thermal Stability and Performance of Foil Thrust Bearings
,”
MS thesis
,
Case Western Reserve University
,
Cleveland, OH
.
13.
Dykas
,
B.
, and
Tellier
,
D.
,
2008
, “
A Foil Thrust Bearing Test Rig for Evaluation of High Temperature Performance and Durability
,”
Army Research Laboratory
,
ARL-MR-0692
.
14.
Lee
,
Y.
,
Kim
,
T.
, and
Kim
,
C.
,
2011
, “
Thrust Bump Air Foil Bearings With Variable Axial Load: Theoretical Predictions and Experiments
,”
Tribol. Trans.
,
54
(
6
), pp.
902
910
. 10.1080/10402004.2011.606957
15.
Kim
,
T.
,
Lee
,
Y.
, and
Kim
,
T.
,
2011
, “
Rotordynamic Performance of an Oil-Free Turbo Blower Focusing on Load Capacity of Gas Foil Thrust Bearings
,”
ASME J. Eng. Gas Turbines Power
,
134
(
2
), p.
022501
. 10.1115/1.4004143
16.
Kim
,
T.
,
Park
,
M.
, and
Lee
,
T.
,
2017
, “
Design Optimization of Gas Foil Thrust Bearings for Maximum Load Capacity
,”
ASME J. Tribol.
,
139
(
3
), p.
031705
. 10.1115/1.4034616
17.
Balducchi
,
F.
,
Arghir
,
M.
, and
Gauthier
,
R.
,
2013
, “
Experimental Analysis of the Start-Up Torque of a Mildly Loaded Foil Thrust Bearing
,”
ASME J. Tribol.
,
135
(
3
), p.
031702
. 10.1115/1.4024211
18.
Balducchi
,
F.
,
Arghir
,
M.
, and
Gauthier
,
R.
,
2015
, “
Experimental Analysis of the Dynamic Characteristics of a Foil Thrust Bearing
,”
ASME J. Tribol.
,
137
(
2
), p.
021703
. 10.1115/1.4029643
19.
Zhou
,
Q.
,
Hou
,
Y.
, and
Chen
,
C.
,
2009
, “
Dynamic Stability Experiments of Compliant Foil Thrust Bearing With Viscoelastic Support
,”
Tribol. Int.
,
42
(
5
), pp.
662
665
. 10.1016/j.triboint.2008.09.005
20.
Lai
,
T.
,
Guo
,
Y.
, and
Wang
,
W.
,
2017
, “
Elasto-Hydrodynamic Lubrication Model of Multi-Decked Foil Thrust Bearing With Copper Wire Support
,”
J. Mech. Technol.
,
31
(
9
), pp.
4371
4379
. 10.1007/s12206-017-0836-3
21.
LaTray
,
N.
, and
Kim
,
D.
,
2018
, “
A High Speed Test Rig Capable of Running at 190,000 rpm to Characterize Gas Foil Thrust Bearings
,”
Proceedings of the ASME Turbo Expo 2018
,
Oslo, Norway
,
June 11–15
, p.
V07BT34A043
.
22.
Khonsari
,
M.
, and
Booser
,
E.
,
2008
,
Applied Tribology: Bearing Design and Lubrication
,
John Wiley & Sons
,
Chichester, UK
,
Chap. 6
, p.
143
.
23.
Ventsel
,
E.
, and
Krauthammer
,
T.
,
2001
,
Thin Plates and Shells-Theory, Analysis, and Applications
,
Dekker
,
New York
,
Chap. 4
, pp.
106
109
.
24.
Kim
,
D.
,
2007
, “
Parametric Studies on Static and Dynamic Performance of Air Foil Bearings With Different Top Foil Geometries and Bump Stiffness Distributions
,”
ASME J. Tribol.
,
129
(
2
), pp.
354
364
. 10.1115/1.2540065
25.
Jones
,
A. B.
,
1960
, “
A General Theory for Elastically Constrained Ball and Radial Roller Bearings Under Arbitrary Load and Speed Conditions
,”
ASME J. Basic Eng.
,
82
(
2
), pp.
309
320
. 10.1115/1.3662587
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