Transcript Presentation - International Conference on Technology

International Conference on TIM, 2012, Nepal
Innovative Design of Francis Turbine for
Sediment Laden Water
Krishna Prasad Shrestha1
Bhola Thapa1,
Ole Gunnar Dahlhaug2
Hari P. Neopane1
Biraj Singh Thapa1
1Dept.
Mechanical Engineering, Kathmandu
University, P.O. Box 6250, Dhulikhel, Nepal
2 Dept. Energy&Process Engineering, Norwegian
University of Science and Technology,
NTNU, Trondheim, 7491, Norway
Email: [email protected]
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Outline
International Conference on TIM, 2012, Nepal
• Introduction
• Objectives
• Methodology
– Design of Francis runner
– Core design process
– Fluid Structure Interaction (FSI)
• Limitations
• Results and Discussion
• Conclusions and Recommendation
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Introduction
International Conference on TIM, 2012, Nepal
• Hydro turbine running in the Himalayas and Andes
Mountain of the South America are facing the same
challenges of sediment erosion
• Jhimruk power plant can be considered a severe one in
Nepal
• Renewable Nepal project, KU and Water power
Laboratory, NTNU has developing Matlab based software
called Khoj
• Khoj facilitates to produce preliminary design data for
Francis turbine with accountability of sediment erosion
• CFD and FSI analysis has greater roll on improvement of
hydraulic machine design and performance analysis
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International Conference on TIM, 2012, Nepal
Runner blade
Francis turbine
Runner blade after
one year of
operation at Jhimruk
Power plant,
Nepal
Stay vane, Scroll
casing, runner
inspection at
Telva Power Plant
Norway
Runner assembly
of Telva Power
Plant Power plant
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Objectives
International Conference on TIM, 2012, Nepal
• To analysis the impact of sand erosion on
Francis turbine.
• To identify the possible solution for the
minimizing effect of erosion on turbine.
• To innovate optimization on Francis Turbine
design.
• To design and develop new Francis turbine.
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International Conference on TIM, 2012, Nepal
Design of Francis runner
• Khoj software generated the data in terms
of guide curves, blade curves, hub curve
erosion factor, Velocity components,
characteristic parameters, turbine
dimensions and corresponding domains
for the CFD analysis
Hub
• On the basis of data prevailed by the
software, turbine blade, hub and shroud
data were imported to Pro/Engineer
software
Shroud
Blade
3D Runner Assembly
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Core design process
SN
1
2
3
International Conference on TIM, 2012, Nepal
Parameters
Net design head(H)
Net discharge per unit(Q)
Runner efficiency()
Value
201.5
2.35
96
Unit
m
m3/s
%
Basic design parameter for JHC
SN
1
2
3
4
5
P1
0.24
0.2
0.28
0.22
0.26
P3
183.794
218.972
160.439
199.2
171.097
P4
4084080
4882860
3486090
4454800
3761720
P5
94.696
93.4553
93.0557
94.5628
94.0276
P6
2.35706
2.35706
2.35706
2.35706
2.35706
P7
104.72
104.72
104.72
104.72
104.72
Optimized values for P1-vel R and head-H
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Core design process
International Conference on TIM, 2012, Nepal
Optimization Layout in ANSYS workbench
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Core design process
Pressure
distribution
International Conference on TIM, 2012, Nepal
Velocity
distribution
Pressure
distribution
R1 Blade
R2 blade
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Core design process
Pressure
distribution
International Conference on TIM, 2012, Nepal
Velocity
distribution
Pressure
distribution
R3 Blade
R4 Blade
R5 blade
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Core design process
International Conference on TIM, 2012, Nepal
• Optimized trade-off charts 1
Efficiency, head, Shaft power and Velocity component Vel-R
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Core design process
International Conference on TIM, 2012, Nepal
• Optimized trade-off charts 2
Efficiency, Flow, Shaft Power and Velocity component Vel-R
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Core design process
International Conference on TIM, 2012, Nepal
• FEM analysis
Pressure distribution on top
cover
Pressure distribution on bottom
cover
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Core design process
International Conference on TIM, 2012, Nepal
• FEM analysis
• FSI Analysis
Guide vane
Boundary condition
location
Stress distribution on
runner Assembly
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Core design process
Deformation on
runner
International Conference on TIM, 2012, Nepal
(Vone Mess ) Stress
distribution on blade
assembly
(Vone Mess) Stress
distribution on single
blade
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International Conference on TIM, 2012, Nepal
Limitations
• Optimization was performed only one set of blade
profile.
• FSI analysis was performed only on Francis turbine
runner assembly.
• During the FSI analysis, Unidirectional Coupling was
chosen, considering there was no large deformation
on runner.
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International Conference on TIM, 2012, Nepal
Results and Discussion
• Optimization was performed on CFD that signifies reducing
simulation and cost of design
• Trade-off chart determines the trade-off points which is used to
show the relation between variables
• Pressure distribution and velocity at trailing were observed by
using CFD analysis
• R2 Blade was selected for FSI analysis since it has found
uniform pressure distribution as well as relatively lower velocity
• FEM analysis was performed on guide vane, upper and lower
cover
• Unidirectional coupled FSI analysis prevailed that total
deformation of runner assembly was 0.00016931m which is safe
for structural steel
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International Conference on TIM, 2012, Nepal
Conclusion and Recommendation
• Erosion problem on Francis turbine due to sand laden water
cannot be stopped completely by current technology but it can
be minimized to the acceptable limit.
• Use of FEM, CFD and FSI tool reduce the design process and
simulation time meticulously.
• New design processes found to be more sophisticated than the
traditional way of design for the Francis turbine.
• Simulated result predicted that the new design method can
accommodate sand erosion problem in more sophisticated
way.
• It is recommended that simulation should be done in whole
turbine unit and for better prediction two-way simulation is
more reliable.
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Recommendation
• It is recommended that simulation should be done in
whole turbine unit and for better prediction two-way
simulation is more reliable.
• Technological challenges and opportunities that recognize
due to innovative design of Francis turbine should adopt
by the turbine manufacturers.
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International Conference on TIM, 2012, Nepal
Thank you very much for
your time and attention!!!
Any queries???
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