1. Analysis of Mixed Flow Turbofan Engine
P M V Subbarao
Professor
Mechanical Engineering Department
Facilitates Afterburner & Serves Defense & Space Applications ….

2. Mixed Flow Turbofan Engine2 1 6c 3 8 6h 7 5 4
Condition for Ideal Mixing:

3. Ideal & Stable Mixer Ideal Mixer : Constant Total Pressure Process.
For a stable operation of the mixer, the inlet static pressures of core flow and fan flow must be equal.
If they are not, back flow will occur in either the fan or core.
The stagnation pressure ratio across the fan:

4. Adiabatic Mixer : 6c+6h -- 7
Adiabatic mixing process:

5. Isentropic Nozzle with Mixed Flow : 7 - 8

6. Velocity of Mixed Jet

7. The Capacity of Mixed flow Jet
Propulsive Power or Thrust Power:
Specific Thrust based on total jet flow S

8. Mixed Flow Turbofan :TSFC

9. Aviation Appreciation
Propulsion Efficiency

10. Mixed –Flow Fan : Effect of Bypass Ratio
Theory of Mixing:
r0p,comp=15
Mac=0.75
0,cc=5.78
Non-dimensional Specific Thrust
Non-dimensional TSFC

11. Subsonic Operation : Mixed Turbo Fan: Mac=0.75
Fan Pressure Ratio
Bypass Ratio
Compressor Pressure Ratio

12. Design Space for Mixed Turbo Fan: Mac=2.0
Fan Pressure Ratio 2
Bypass Ratio 3 4 5
Compressor Pressure Ratio

13. Subsonic Operation : Mixed Turbo Fan : Mac=0.75
Fan Pressure Ratio 2 3
Specific Thrust kN.s/kg 4 5
Compressor Pressure Ratio

14. Supersonic Operation : Mixed Turbo Fan : Mac=2.0
Fan Pressure Ratio 2 3
Specific Thrust N.s/kg 4 5
Compressor Pressure Ratio

15. Effect of Mach Number : Mixed Turbo Fan
2:0.75
2:2.0
Specific Thrust kN.s/kg
4:0.75
4:2.0
Compressor Pressure Ratio

16. Subsonic Operation : Mixed Turbo Fan : Mac=0.75
Fan Pressure Ratio 5
TSFC 4 3 2
Compressor Pressure Ratio

17. Supersonic Operation : Mixed Turbo Fan : Mac=2.05
Fan Pressure Ratio 4 3 2
TSFC
Compressor Pressure Ratio

18. Effect of Mach Number : Mixed Turbo Fan
4 :2.0
2:2.0
Fan Pressure Ratio
TSFC
4 :0.75
2:0.75
Compressor Pressure Ratio

19. Designs for Better Fuel Economy: Subsonic Flight5
TSFC
Fan Pressure Ratio
TSFC 4 3
Bypass Ratio
Fan Pressure Ratio 2
Compressor Pressure Ratio
Compressor Pressure Ratio

20. HAL Tejas Mark 2:- Advanced Variant of LCA Tejas
GE Aviation has handed over two F414-GE-INS6 engines which will eventually power Tejas MK-II by 2020 in Feb 2017.
98 kN thrust.
The Tejas Mark 2 may feature an indigenously developed active electronically scanned array (AESA) fire control radar named Uttam.

21. TF30: Pratt and Whitney Mixed Flow Turbofan Engine
The TF30−P−414 engine is a mixed−flow, dual spool afterburning low−bypass turbofan designed and manufactured by Pratt and Whitney.
The engine incorporates a nine−stage low pressure compressor including a three−stage fan driven by a three−stage low pressure turbine; and a 7−stage axial flow high−pressure compressor driven by a single−stage high−pressure turbine.

22. SPECIFICATIONS:TF30
Max Design Pressure Ratio: Fan: 2.14 to 1 Overall: 19.8.
Three−stage fan +Nine−stage low pressure compressor driven by a three−stage low pressure turbine;
7−stage axial flow high−pressure compressor driven by a single−stage high−pressure turbine.
The variable−area exhaust nozzle is hydraulically actuated, 508 to 1080 sq. in
Airflow Capacity: Bypass airflow ratio: to 1
Max rated airflow: lbs/s
Max rated turbine inlet: 2150F

23. F110-GE-129 Mixed Flow Turbofan Engine

24. Details of F110-GE-129 : October 2015
The F110-GE-129 engine was selected to power the latest version of the F-15 aircraft ordered by the Republic of Korea.
The first F-15K took to the skies powered by F110 engines in March 2005.
Samsung TechWin will manufacture in Korea 78 of the 88 engines purchased by the Republic of Korea Air Force (ROKAF) for the F-15K program.

25. SPECIFICATIONS:F110-GE - 400
Thrust :129 kN
Airflow :122.4 kg/sec
Bypass ratio : 0.76
Max Design Pressure Ratio, SLS:Fan:3.2 to 1
Overall: 29.9 to 1
Airflow Capacity: Max rated airflow: lbs/s

26. Twin Spool Turbofan Engine

27. Rolls Royce RB211-535 Engine : Three Spool Turbofan Engine

28. Options for Highest Fuel Economy
TSFC
ropfan,opt a

29. PW1100G : High Bypass ratio : 12.5