6. chapter 7 Compressor and Turbine

7. 7-1 Classification of Compressor compressor Positive displacementTurbine reciprocatingrotarycentrifugalaxial flow This is the type we will study

8. 7-2 Compressor Work 7-2-1 The cycle of compressor p v

9. 7-2-2 Compressor Work

11. If isothermal If isentropic If polytropic

12. p v Isothermal Polytropic Isentropic

13. 7-3 Real compressor 7-3-1 Clearance volume

14. 7-3-2 The effect of Clearance volume p v

15. 7-4 Multistage Compression with Intercooling p v p1p1 p2p2 pmpm B A

16. Since p 1 v 1 =p m v m

17. To get the minimum work Then:

18. 7-5 Steam Turbine 7-5-1 Steam Turbine

22. 7-5-2 h-s Diagram h s c p1p1 p2p2 T1T1 T2T2 v X=0.8 (1)constant pressure curves (2) Isothermal curves (3) constant specific volume curves (4) constant dryness fraction curves X=1 X=0.6 X=0

23. 7-6 Adiabatic Efficiency of Steady-Flow Devices 7-6-1 Compressor If an adiabatic compressor:

24. 1 2 Draw the process on a h-s diagram But if the process is an irreversible process, it will be: h s P2P2 P1P1 w 2’ w’ Therefore we define the inner efficiency of compressor as following: This equation can also be used for pump

25. 7-6-2 Turbine If an adiabatic turbine: 2 1 h s P1P1 P2P2 w w’ Therefore we define the inner efficiency of turbine as following: 2’ This equation can also be used for nozzle If irreversible:

26. The end of this chapter