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

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

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:

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

Isentropic Nozzle with Mixed Flow : 7 - 8

Velocity of Mixed Jet

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

Mixed Flow Turbofan :TSFC

Aviation Appreciation Propulsion Efficiency

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

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

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

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

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

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

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

Supersonic Operation : Mixed Turbo Fan : Mac=2.0 5 Fan Pressure Ratio 4 3 2 TSFC Compressor Pressure Ratio

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

Designs for Better Fuel Economy: Subsonic Flight 5 TSFC Fan Pressure Ratio TSFC 4 3 Bypass Ratio Fan Pressure Ratio 2 Compressor Pressure Ratio Compressor Pressure Ratio

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.

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.

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: 0.878 to 1 Max rated airflow: 242.0 lbs/s Max rated turbine inlet: 2150F

F110-GE-129 Mixed Flow Turbofan Engine

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.

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: 270.0 lbs/s

Twin Spool Turbofan Engine

Rolls Royce RB211-535 Engine : Three Spool Turbofan Engine

Options for Highest Fuel Economy TSFC ropfan,opt a

PW1100G : High Bypass ratio : 12.5