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Let us now consider the analysis of the turbofan

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Let us now consider the analysis of the turbofan configuration shown in Figure 2. The following parameters are assumed to be specified: Figure 3: T-s diagram for turbofan engine
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Figure 4: T-s diagram for Fan part Fan analysis Fan efficiency; 1 2 1 ' 2 T T T T fan - - = η Fan nozzle efficiency; 2 ' 9 2 9 T T T T Nozzlefan - - = Fan work, ) ( 1 2 T T C w p fan - = Fan jet energy, ) ( 2 9 2 2 T T C V p jetFan - = Thrust net, a a NozleFan c nozle f H n V m V m V m m F - + + = ) ( H c m m = β , H f m m f = , H c a m m m + = TSFC, n f F m TSFC =
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Turboprop Engine A Turboprop engine is a type of gas turbine engine used in aircraft. Most of a turboprop engine's power is used to drive a propeller, and the propellers used are very similar to the propellors used in piston or reciprocating engine-driven aircraft (with the exception that turboprops usually use a constant velocity propeller). A turboprop engine is similar to a turbojet, but has additional fan blades in the turbine stage to recover more power from the engine to turn the propeller. Turboprop engines are generally used on small or slow subsonic aircraft, but some aircraft outfitted with turboprops have cruising speeds in excess of 500 kts (575 mph). A turboprop consists of an intake, compressor, combustor, turbine and a propelling nozzle. Air is drawn into the intake and compressed by the compressor. Fuel is then added to the compressed air in the combustor. The hot combustion gases expand through the turbine, to provide power to the turbine. Part of this power goes to the compressor, and the rest, through the reduction gearing, to the propeller. Further expansion of the gases occurs in the propelling nozzle, where the gasses are expelled, providing about a quarter of the thrust. Turboprops are very efficient at modest flight speeds (below 450 mph), because the jet velocity of the propeller (and exhaust) is relatively low. Due to the high price of turboprop engines, they are mostly used where high performance Short-Takeoff and Landing (STOL) capability and efficiency at modest flight speeds is required. In a civilian aviation context, the most common application of turboprop engines are small commuter aircraft.
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Analysis and T-s diagram of the turbofan engine is as same as turbojet except: Shaft horse power, ft drivingSha w SHP = ESHP, nozzlejet w SHP ESHP + = [Hp] ESFC, ESHP m ESFC f = [kg/sec/Hp]
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Let us now consider the analysis of the turbofan...

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