1. Impact of Cycle Design on Steam Generator
P M V Subbarao
Professor
Mechanical Engineering Department
The strongest Measures of Development….

2. Basic The Theme Steam Generator Design
Constrains:
Imposed by Cycle Design (pmax, Tmax, etc.)
Fuel Combustion Related.
Heat Transfer Related
Safety and Reliability Related.

3. The Basic Rankine Cycle

4. Gas to Liquid Heat Exchange
Liquid Heating

5. The Power Gods ~1760 : James Watt ~1820 : Sadi Carnot
George Brayton & W Rankine ~ 1860

6. Law of Power Generation
Coal (Source)
Power Plant
--Cycle Design
-- Equipment Design
--Equipment Operation
Land, Water & Air (Sinks)

7. Progress in Rankine Cycle
Year
1907
1919
1938
1950
1958
1959
1966
1973
1975 MW 5 20 30 60
120
200
500
660
1300
p,MPa
1.3
1.4
4.1
6.2
10.3
16.2
15.9
24.1
Th oC
260
316
454
482
538
566
565
Tr oC --
FHW 2 3 4 6 7 8
Pc,kPa
13.5
5.1
4.5
3.4
3.7
4.4
5.4
h,%
~17
27.6
30.5
35.6
37.5
39.8
39.5 40

8. Role of SG in Rankine Cycle
Perform Using Natural resources of energy …….

9. Impact of cycle on Construction of Steam Generator
Superheater
Evaporator
Economizer

10. Trends in coal-fired generation : Performance
The average efficiency of coal-fired generation is projected to increase from 34% in 2006 to 36% in 2015 and to 38% in 2030.
In the OECD, efficiency increases from 37% to 41%.
In non-OECD countries, efficiency improves from 31% to 37% because new coal-fired power plants built to meet rapidly growing electricity demand are expected to be far more efficient than existing ones.

11. Modern Measure of Performance

12. The Rankine Cycle

13. Pump : Isentropic Process1 2
SSSF: Conservation of mass
First Law :
No heat transfer, change in kinetic and potential energies are negligible

14. 2 – 3 : SG: Isobaric Heating : p3 = p2
QCV 3 2
No work transfer, change in kinetic and potential energies are negligible
Assuming a single fluid entering and leaving…

15. Constant Pressure Heating Process

16. Constant Pressure Heating Process
Vapour
Liquid +Vapour h
Liquid s

17. Ideal Rankine Cycle

18. Constant Pressure Heating Process