1. Analysis of Power Generation Cycles
P M V Subbarao
Professor
Mechanical Engineering Department
Development of Techno-economically Feasible Thermodynamic Model

2. Schematic of Rankine & Brayton cycles

3. Global Accounting of Energy Interactions
First law for a cycle:

4. Net Power output (Income) of A Cycle

5. Basic Expenditure in A cycle

6. First Law Analysis & Figure of Merit for the Cycle

7. Ideal Rankine Cycle : P-h Diagram
pmax=17Mpa
=42.05% 1 2 3 4
Tmax=5500C 1 2 3 4
pmax=5Mpa
=37.8%

8. Ideal Rankine Cycle : P-h Diagram
Tmax=5500C
Tmax=4500C
Tmax=6000C 1 2 3 4

9. Selection of Optimum Boiler Pressure
Tmax = 450 oC h
Pressure, MPa

10. pmax=10MPa

11. Parametric Study of Rankine Cycle
D.S.S.
3000C h
P max

12. Parametric Study of Rankine Cycle
23.5MPa
22MPa
18MPa
10MPa
6MPa
D.S.S.
3MPa h
1MPa
Tmax

13. 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

14. Layout of A Modern Power Plant

15. Brayton Cycle : Working with Single Phase –Substance
Qin
Qout
Wout

16. Brayton Cycle for Power Generation
1-2 Adiabatic compression (in a compressor)
2-3 Constant pressure heat addition
3-4 IAdiabaticexpansion (in a turbine)
4-1 Constant pressure heat rejection

17. Thermodynamic Analysis of Adiabatic Compression
For an infinitesimal compression:

18. Adiabatic Process by an Ideal Gas
For an infinitesimal compression of perfect gas:

19. Model for infinitesimal Adiabatic Process by a perfect Gas