European COMSOL Multiphysics Conference (Milan 2012) Download for a better experience. https://esp.comsol.com/paper/multiphysics-modeling-of-spring-supported-thrust-bearings-for-hydropower-applica-13019

1. F. Xavier Borràs*1, Jan Ukonsaari2 and Andreas Almqvist1
1Luleå University of Technology, Division of Machine Elements, Luleå, Sweden;
2Vattenfall, Vattenfall Research and Development AB, Luleå, Sweden.
*Corresponding author: Luleå University of Technology, 97 187 Luleå (Sweden),
borrasfx@gmail.com
Multiphysics Modelling of Spring-
Supported Thrust Bearings for
Hydropower Applications

2. Thrust bearings are commonly used in
hydroelectric power plants. These bearings
are required to support the shafts of the
turbines.
1.1) Thrust Bearings
THRUST BEARING
1
2
3

3. 3. Collar
2. Fluid
1. Pad
The relative motion between the collar and the
pads generates a pressure distribution.
COLLAR
PAD SUPPORT
External Load
Pressure
distribution
p
1.2) HOW does it work
Fluid Velocity
Field
U
GAP GEOMETRY • Elastic Deformation
• Thermal Expansion
• Tilting
1
2
3
Gap Height h

4. • The pad is supported
by a spring mattress.
• There is not a defined
pivot point.
1.3) Spring-Supported
1
2
3

5. A.) PAD
B.) COLLAR
C.) FLUID
2) Model
1
2
3

6. 2.1) Physics Applied
C
O
L
L
A
R
F
L
U
I
D
P
A
D
MM
HTf
HTs
SM
LS
Heat Transfer in Solids
Solid Mechanics
Moving Mesh
(mesh deformation)
Lubricant Shell
Heat Transfer in Fluids
SM
HTs
HTf
MM
LS
SM
HTs
1
2
3

7. 2.2) Model Coupling
C
O
L
L
A
R
F
L
U
I
D
P
A
D
pf
pf
pf
u,v,z
hwall
u,v,z
T
T
T
X,Y,Z
hchannel
u,v,z
T
u,v,z
SM
HTs
HTf
MM
LS
SM
HTs
1
2
3

8. OUTPUTS
Pressure on the Gap
PAD
Deformation
Temperature
COLLAR
Deformation
Temperature
FLUID
Film Thickness
Temperature
Power Losses
INPUTS
Shaft Angular Velocity
External Load Applied
Bath Temperature
Geometry Parameters
Material Proprieties
Springs Pattern
Characteristics
Spring-Supported Thrust
Bearing Model
3) RESULTS: Global Scheme
1
2
3

9. HOW does it work? Springs
3.1) Results
Pressure on the Gap
Fluid Velocity
Field
Pad Temperature
Fluid Film Thickness
Collar Displacement
1
2
3

10. 3.2) Applications of the Model
• Varying operating conditions:
a) Load
b) Angular Velocity
c) Bath Temperature
d) Springs Patterns
• Test different kinds of lubricants.
• Test different compounds materials.
• Test shape improvements.
1
2
3

12. F. Xavier Borràs*1, Jan Ukonsaari2 and Andreas Almqvist1
1Luleå University of Technology, Division of Machine Elements, Luleå, Sweden;
2Vattenfall, Vattenfall Research and Development AB, Luleå, Sweden.
*Corresponding author: Luleå University of Technology, 97 187 Luleå (Sweden),
borrasfx@gmail.com
Multiphysics Modelling of Spring-
Supported Thrust Bearings for
Hydropower Applications