H.V. Pre – conference workshop
27
th
July. 2010
Shogo Nakamura
(Voith Fuji Hydro, K.K.)
Development of
Vertical Bulb Turbines
1.
Renovation plan in Agano and Tadami river
2.
Kaminojiri No.2 (Vertical bulb turbine)
3.
Intake stricture development
4.
E & M development
5.
Toyomi S & B proje
Presentation Contents
page 3
page 4 - 7
page 8 - 10
page 11 - 17
page 18 - 24
BOD Presentation – OU xxx – Autumn 2008.ppt | 2
1. Renewable plan in Agano and Tadami rivers
1963
27MW 2 units
VK
Agekawa
1973
55MW 1 unit
VK
Kanose No.2
1928
8MW 6 units
VF
Kanose
1975
57MW 1 unit
VK
Toyomi No.2
1929
10MW 6 units
VF
Toyomi
2001
14MW 1 unit
VB
Kaminojiri No.2
1958
17MW 3 units
VF
Kaminojiri
1993
25 MW 1 unit
HB
Yamazato No.2
1933
15MW 3 units
VF
Yamazato
1984
39MW 1 unit
HB
Shingo No.2
1939
13MW 4 units
VF
Shingo
1953
19MW 3 units
VF
Katakado
1953
25MW 3 units
VF
Yanaizu
1954
26MW 3 units
VF
Honna
Inst. Year
Capacity MW
Type
1. Renewable plan in Agano and Tadami rivers
Tokyo
Sendai
Niigarta
Lake
Inawashiro
Tadami
Agano
Kaminojiri
2. KAMINOJIRI No.2 / VERTICAL BULB - Plan view
Existing units
Vertical bulb
14MW
2. KAMINOJIRI No.2 / VERTICAL BULB - Elevation view
Vertical bulb
Existing Kaminojiri
Kaminojiri No.2
2. Kaminojiri No.2 - Comparison of Power House size
Vertical Bulb
Horizontal Bulb
Vertical Kaplan
11.
5m
φ8.5m
13
m
φ8
.3
m
φ4
.4
m
Total plant cost is
reduced by 14 %
Power house floor
is reduced by 30 %
Overhaul duration
is reduced by 33 %
3. Intake structure development
Entrained air bubbles induce vibration and power swing
Air taking
Air taking
Intake
Intake
flow
flow
Casing
3. Intake structure development
Anti vortex stabilizer was developed by hydraulic
scaled model
Stabilizer
Stabilizer
Intake
Intake
flow
flow
3. Intake structure development
Intake
Anti vortex stabilizer
(Before setting)
Anti vortex stabilizer
(set position)
4. E & M development
Basic concept
1.
Minimum plant cost
2.
Minimum maintenance cost
3.
Maximum reliability
Direct heat
dissipation (stator)
Location of access
shaft
Fin cooling
Minimum Plant Cost
Water lubricated
bearing
Twin bearing
structure
Experiences in bulb
machines
5 bladed runner
Maximum Reliability
Direct heat
dissipation (bearing)
Experiences in
Kaminojiri No.2
Minimum
Maintenance
Improved bulb
bracket
PTFE thrust bearing
4. E & M development
Basic concept
4. E & M development (Runner)
Bend-draft tube has negative
effect on turbine efficiency
Runner diameter was
selected to attain optimum
turbine efficiency
HB
VB
HB
VB
4. E & M development
Minimum maintenance cost
Direct heat dissipation
(Generator stator)
Ventilation air cooling
through fins
Direct heat dissipation
(thrust bearing)
River water
Bearing
4. E & M development
Maximum reliability
①Strain (stress)
End and center of bulb bracket rib
Inner casing
②Vibration mode and natural frequency
Strain gauges were attached at the locations
specified from simulation and strain was
measured during water filling stage.
Field test at Kaminojiri No.2
③BB rib end
②BB rib center
①Inner casing
Access shaft
4. E & M development
Maximum reliability
Stress simulation and comparison
G.V.
Bulb Bracket
Inner Casing
BB rib end
BB rib center
Inner casing pressure
Error(%)
FEM
Meas.
BB rib end (Z)
-9.5
-9.57
+0.7
BB rib center (Z)
12.1
9.51
-27
Inner casing (X)
-1.94
-1.78
-9
Watered(GV open)
Meas. (kgf/mm2)
4. E & M development
Maximum reliability
Rotor
Stator
Runner
Access
Shaft
Exciter
Bulb bracket
Guide vane
Temperature simulation
and comparison
River water;
12.2
℃
Stator temp.
Calc.; 88.2
℃
Meas.; 76.7
℃
Error; -18%
Bearing temp.
Calc.; 49.1
℃
Meas.; 44.9
℃
Error; -8.5%
5. Toyomi
S & B project
(6 x 10 MW Vertical Francis → 2 x 30 MW Vertical bulb)
Streamlines and Pressure
distribution around Wicket Gates
Strength
analyses
Leakage flow from runner gap
( for design of runner hub contour)
Pressure distribution on runner
( for prediction of cavitation )
5. Toyomi S & B project
Model
acceptance
test
2009 Jan.
5. Toyomi S & B project
Vortex takes
air bubble
Intake vortex problem
Influence of the intake
vortex for the turbine
1.Unit Vibration
2.Noise
3.Power swing
5. Toyomi S & B project
-10
-8
-6
-4
-2
0
2
4
0
10
20
30
40
50
t [sec]
Cp=
2
⊿
p/
ρVi
n
2
[-]
上流側水車
下流側水車
Flow speed and Vector plot
Pressure Fluctuation
Vortex Method is unsteady calculation. Therefore, it is good
method to solve the unsteady intake vortex problem.
CFD - 3D Vortex Method is applied for the optimization
Intake optimization
5. Toyomi S & B project
After CFD tuning by
prototype test
Before CFD tuning by
prototype test
•Inflow condition (River flow CFD)
•Fine mesh
Intake optimization
5. Toyomi S & B project
Intake optimization
-10
-8
-6
-4
-2
0
2
4
0
10
20
30
40
50
t [sec]
Cp=2
⊿
p/
ρVi
n
2
[-]
上流側水車
下流側水車
No vortex on water surface
Small pressure fluctuation
Final design
Anti vortex stabilizer
5. Toyomi S & B project
Existing Toyomi power house under scrapped