1. Turbines for Steam Power Plants
P M V Subbarao
Professor
Mechanical Engineering Department
I I T Delhi
Selection of Materials and Shape for Strong & Enduring Non-Biological Muscles ……

2. Development of A Sustainable Non-Biological Beast
The steam Power Plant is the largest non-biological beast .
Needs an elaborate anatomy for efficient conversion of chemical energy into Mechanical/Electrical energy.
The working fluid is the blood of this animal.
The pump is the heart of this beast & cyclically induces life into the working fluid.
The steam generator is the digestion system of this beast.
The steam turbine is the Muscle system of this beast.
The supercritical steam turbines are the strongest and most efficient non-biological muscles.
An essential requirement for human development.

3. KP is Like ATP

4. High Pressure
High MKE Steam System
Shaft power to generator
Dead Steam
Dead must be properly recycled

5. Power Plant Steam Turbines
A Two Step Conversion of Microscopic Kinetic Power to Shaft Power…….

6. Work is said to be done by a system iff
Thermodynamic Validation of Flowing Steam Work
Low KP
High MLP Vi
High KP
Negligible MLP Ub Ve
Low KP
Low MLP
Work is said to be done by a system iff
the sole effect external to the system
can be reduced to raising of weight

7. Sign is important part of this definition.
The Steam Turbine
The more modern device to extract shaft power from Microscopic kinetic Power is the steam turbine.
Steam turbines have been the norm in various land based power plants for more than 100 years.
Turbine is a flow device develops a variable pressure form inlet to outlet.
A flowing steam performs work transfer, while moving from high inlet pressure (Live Steam) to low outlet pressure (Dead Steam).
The volume of steam continuously increases during this process.
The infinitesimal work done by a flowing fluid is defined as
Sign is important part of this definition.
Steam flowing in the direction of decreasing pressure performs +ve work.

8. Continuous Generation of Power
How to introduce finite mass flow rate of steam?
Area for Flow of Fluid.
Proportional to the Length of the Blade.
More Number of Blade Spacings.

9. Concept of Two Step Conversion : Kinetic Power to Shaft Ppwer
Steam turbine is a two part device:
Part 1:Energy Converter : Nozzles or Stationary Blades
Part 2: Energy Exchanger: Rotor or Moving Blades.

10. Classification of Rotors or Rotor Blades
Single Job Rotors: Only Exchange of Macro Kinetic Power from steam to Shaft Power via blades.
Also called as Impulse Blades/rotor.
Dual Job Rotors: Both energy conversion and Energy Exchange.
Known as Reaction Blades/rotor.
Best choice for Large Power Plant Turbines

11. Nozzle wheel and Blade Wheel

12. Top View of the Steam & Blade Interactions
Va1 U
Vr1
Va1
Inlet Velocity Triangle
Vr1 U U
Vr2
Va2
Exit Velocity Triangle
Vr2

13. The Velocity TrianglesU a2 a1 b2 b1
Va1
Va2
Vr1
Vr2
Va1: Inlet Absolute Velocity
Vr1: Inlet Relative Velocity
Vr2: Exit Relative Velocity
Va2:Exit Absolute Velocity
a1: Inlet flow Angle.
b1: Inlet Blade Angle.
b2: Exit Blade Angle.
a2: Exit flow Angle.

14. Selection of The Velocity TrianglesUb
Vr1
Va1 b1 a1 a2 b2 U
Vr1
Va1
Vr2
Va2 b1 a1 a2 b2
Va2 U
Vr1
Va1
Vr2
Va2 b1 a1 a2 b2
Vr2 U
Vr1
Va1
Vr2
Va2 b1 a1 a2 b2
Va1: Inlet Absolute Velocity
Vr1: Inlet Relative Velocity
Vr2: Exit Relative Velocity
Va2:Exit Absolute Velocity
a1: Inlet flow Angle.
b1: Inlet Blade Angle.
b2: Exit Blade Angle.
a2: Exit flow Angle.

15. Blade Shape

16. Mechanical Arrangements of Steam Turbines
The blade velocity is defined at mean diameter of rotor wheel.
For same wheel speed, the blade velocity is directly proportional to blade height.
The height of the blade is proportional to specific volume of steam.
Solutions to Turbo-machinery Speed Issues (TSI).
Tandem Reheat Steam Turbine
Cross Compound Steam Turbine

17. Tandem Reheat Steam Turbine

18. Cross Compound Reheat Steam Turbine

19. Tandem-compound four-flow steam turbine

20. Large-Capacity Steam Turbines for Fossil Thermal Power Plant

21. Some Facts about Advanced Steam Turbines

22. Increased Magnitudes of Forces

23. Steam Volume Variation HP Range
Specific volume, m3/kg
Steam Path, Mpa

24. Steam Volume Variation IP Range
Specific volume, m3/kg
Steam Path, Mpa

25. Steam Volume Variation LP Range
Specific volume, m3/kg
Steam Path, Mpa

26. Bleeding for FWHs : A win-win Idea

28. Efficiency of USC Turbine Modules:800MW

29. Typical ~ 500 MW Designs

30. Typical ~ 800 MW Designs

31. ~ 1000 MW Designs

32. Reduction of Stage Losses

33. High-performance blading : Advanced Aero Design

34. Advanced Blades for ST

35. Modular Concept of Blade Construction

36. Major equipment in A Power Plant

37. Exhaust Diffuser For L P Turbine

38. Large Power Plant Condenser