Engine Presentation

Advancement in Gas Advancement in Gas Turbine PropulsionTurbine Propulsion

Presentation is Divided Presentation is Divided into Three Chaptersinto Three Chapters�� 1. Gas Turbine Engine 1011. Gas Turbine Engine 101�� 2. Engine Systems of the Industry’s 2. Engine Systems of the Industry’s current Enginescurrent Engines�� 3. Future Technologies in Gas Turbine 3. Future Technologies in Gas Turbine PropulsionPropulsion

Chapter 1Chapter 1Gas Turbine Engine 101Gas Turbine Engine 101

Gas turbine EngineGas turbine Engine�� Member of the Reaction Engine Family, Member of the Reaction Engine Family,

whose sole purpose is to accelerate or whose sole purpose is to accelerate or produce high velocity gases at the exit produce high velocity gases at the exit nozzle. This produces an increase in nozzle. This produces an increase in momentum, and provides thrust.momentum, and provides thrust.

Standard Day ConditionsStandard Day Conditions�� The standard day conditions are zero The standard day conditions are zero percent humidity, 15 degrees C (59 percent humidity, 15 degrees C (59 degrees F) and atmospheric pressure degrees F) and atmospheric pressure of 29.92 in Hg at sea level.of 29.92 in Hg at sea level.

�� Standard day conditions are used by Standard day conditions are used by engineers when calculating the engine engineers when calculating the engine thrust ratings.thrust ratings.

Standard Day ConditionsStandard Day ConditionsAs air temperature increases, engine power output decreases, and vice versa.

As air density increases, engine power output increases, As air density decreases, engine power output decreases.

Newton’s Law of MotionNewton’s Law of Motion�� Newton’s Second and Third Law of Motion helps Newton’s Second and Third Law of Motion helps explain how a jet engine produce thrust.explain how a jet engine produce thrust.�� Newton’s Second Law of Motion identifies how Newton’s Second Law of Motion identifies how acceleration is produced when a force acts on a acceleration is produced when a force acts on a mass. The heavier the mass of the object mass. The heavier the mass of the object accelerated, the larger the amount of force accelerated, the larger the amount of force necessary to accelerate the object.necessary to accelerate the object.�� Newton’s Third Law of Motion states “Every action Newton’s Third Law of Motion states “Every action has an equal and opposite reaction.” For example, has an equal and opposite reaction.” For example, if a 200 pound man jumps off the back of a 200 if a 200 pound man jumps off the back of a 200 pound boat, the man and the boat will move in pound boat, the man and the boat will move in equal distance.equal distance.

Newton’s Law of MotionNewton’s Law of Motion�� Newton’s Third Newton’s Third Law of Motion Law of Motion states “Every states “Every action has an action has an equal and equal and opposite opposite reaction.” reaction.” �� For example, if For example, if a 200 pound a 200 pound man jumps off man jumps off the back of a the back of a 200 pound 200 pound boat, the man boat, the man and the boat and the boat will move in will move in equal distance.equal distance.

�� Newton’s Newton’s Second Law of Second Law of Motion states Motion states “Force equals “Force equals mass mass accelerated.”accelerated.”�� The greater the The greater the quantity of air quantity of air the jet engine the jet engine accelerates the accelerates the larger the larger the amount of amount of thrust being thrust being produced.produced.

Newton’s Law of MotionNewton’s Law of Motion

�� Newton’s Third Newton’s Third Law of Motion Law of Motion states “Every states “Every action has an action has an equal and equal and opposite opposite reaction.”reaction.”�� Action; jet Action; jet exhaust going exhaust going through the jet through the jet engine. engine. �� Reaction; jet Reaction; jet engine is engine is propelled propelled forward. forward.

Newton’s Law of MotionNewton’s Law of Motion

Bernoulli’s PrincipleBernoulli’s Principle�� Bernoulli’s Principle Bernoulli’s Principle says air that moves says air that moves through a tube that through a tube that decreases in diameter decreases in diameter (convergent duct) will (convergent duct) will increase in velocity and increase in velocity and decrease in pressure. decrease in pressure. Air that moves through Air that moves through a tube that increases in a tube that increases in diameter (divergent diameter (divergent duct) will decrease in duct) will decrease in velocity and increase in velocity and increase in pressure.pressure.

Balanced ForcesBalanced Forces�� Balanced forces are Balanced forces are forces acting on an forces acting on an object that are the object that are the same in every same in every direction.direction.�� Balanced forces on Balanced forces on an object prevent an object prevent movement. If forces movement. If forces on an object are the on an object are the same in all same in all directions the object directions the object will not move.will not move.

Balanced ForcesBalanced Forces�� Unbalanced forces Unbalanced forces are forces on an are forces on an object that are not object that are not the same in all the same in all directions. During directions. During operation a jet engine operation a jet engine pushes gases out the pushes gases out the exhaust nozzle. This exhaust nozzle. This makes an unbalanced makes an unbalanced force towards the force towards the front of the engine.front of the engine.

��Unbalanced forces cause an object to Unbalanced forces cause an object to move. Unbalanced forces cause the jet move. Unbalanced forces cause the jet engine to produce thrust.engine to produce thrust.

Increasing ThrustIncreasing Thrust�� Jet engine thrust can be increased two Jet engine thrust can be increased two

ways:ways:

Increasing ThrustIncreasing Thrust–– Increase the speed of the exhaust gases.Increase the speed of the exhaust gases.

Increasing ThrustIncreasing Thrust–– Increase the quantity of the exhaust Increase the quantity of the exhaust

gases.gases.

�� Increased engine thrust will make an aircraft fly faster or Increased engine thrust will make an aircraft fly faster or with more weight.with more weight.

Gas Turbine Engine Gas Turbine Engine OperationOperation�� The engine is started by rotating the The engine is started by rotating the

compressor with a starter, and then igniting the compressor with a starter, and then igniting the mixture of fuel and air in the combustion mixture of fuel and air in the combustion chamber with one or more igniters. When the chamber with one or more igniters. When the engine has started and its compressor has engine has started and its compressor has gained sufficient speed, the starter and igniters gained sufficient speed, the starter and igniters are turned off. The engine will run without are turned off. The engine will run without further assistance as long as fuel and air in further assistance as long as fuel and air in proper proportions continue to enter the proper proportions continue to enter the combustion chamber.combustion chamber.

Gas Turbine Engine Gas Turbine Engine OperationOperation

Powerplant – Engine and interface to aircraft systems




Gas Turbine Engine Gas Turbine Engine OperationOperation�� AirAir entersenters thethe inletinlet ductsducts thenthen passespasses throughthrough

thethe compressorcompressor.. TheThe compressorcompressor increasesincreases thethepressurepressure ofof thethe incomingincoming airair beforebefore passingpassing itittoto thethe combustioncombustion chamberchamber..





Gas Turbine Engine Gas Turbine Engine OperationOperation�� FuelFuel isis sprayedsprayed throughthrough thethe nozzlesnozzles toto thethe frontfront

ofof thethe combustioncombustion chamberchamber.. TheThe resultingresultingmixturemixture ofof fuelfuel andand airair isis burnedburned toto produceproducehot,hot, expandingexpanding gassesgasses thatthat rushrush toto thethe turbineturbinesection,section, causingcausing thethe turbineturbine rotorsrotors toto rotaterotate..



COMBUSTION CASE FRONT FLANGE

COMBUSTION CASE

COMBUSTION CHAMBER

COMBUSTION CASE REAR FLANGE

ENERGY

HP TURBINE SECTION

COMBUSTOR INTERFACES


CENTER VENT TUBE

LPT ROTORTURBINE FRAME

Gas Turbine Engine Gas Turbine Engine OperationOperation�� OnOn leavingleaving thethe turbineturbine section,section, thethe gassesgasses areare

expelledexpelled toto thethe outsideoutside airair throughthrough thethe exhaustexhaustductduct andand jetjet nozzlenozzle.. TheThe powerpower thatthat thethe turbineturbinerotorsrotors extractextract fromfrom thethe expandingexpanding gasesgases isis usedusedtoto drivedrive thethe compressorscompressors.. AsAs thethe turbineturbine rotorsrotorsandand compressorcompressor areare bothboth mountedmounted onon thethe samesameshaftshaft.. TheyThey operateoperate asas aa unitunit..

�� !! TheThe secretsecret whywhy aa gasgas turbineturbine willwill runrun asas ititdoesdoes lieslies inin thethe compressorcompressor..


�� Turbojet or StraightjetsTurbojet or Straightjets

�� Turbofan or Fanjet Turbofan or Fanjet

�� Turboprop or PropjetsTurboprop or Propjets

�� Turboshaft or Shaft Turbine EngineTurboshaft or Shaft Turbine Engine

Types of Jet Engines For Types of Jet Engines For AircraftAircraft

Turbojet or StraightjetsTurbojet or Straightjets�� A gas turbine A gas turbine

engine that uses engine that uses only thrust only thrust developed within developed within the engine to the engine to produce propulsive produce propulsive force. Have no force. Have no other features other features such as fan, such as fan, propeller or free propeller or free turbine.turbine.

Turbojet or straightjetsTurbojet or straightjets

Turbojet or straightjetsTurbojet or straightjets

�� Efficiencies of turbojets are attained at high Efficiencies of turbojets are attained at high altitude and airspeed.altitude and airspeed.

�� High thrust at low airspeed is not a turbojet High thrust at low airspeed is not a turbojet characteristic.characteristic.

�� To be at their best, turbojets need ram air To be at their best, turbojets need ram air pressure that comes only with high airspeed. pressure that comes only with high airspeed.

�� Turbojets need long runway for takeTurbojets need long runway for take--off.off.

Characteristics of Characteristics of TurbojetsTurbojets

Types of Jet Engine Types of Jet Engine ProfileProfile�� ConventionalConventional

�� Wasp WaistWasp Waist

Types of Jet Engine Types of Jet Engine ProfileProfile

TurbopropTurboprop�� When the When the

exhaust gases exhaust gases from the basic from the basic part of a turbojet part of a turbojet (often called gas (often called gas generators) are generators) are used to rotate an used to rotate an additional turbine additional turbine that drives a that drives a propeller through propeller through a speed reduction a speed reduction gear system, the gear system, the engine becomes a engine becomes a turboprop.turboprop.

TurbopropTurboprop

Types of TurbopropsTypes of Turboprops�� Direct propeller drive turboprop Direct propeller drive turboprop –– power power

produced drives the propeller reduction gearing produced drives the propeller reduction gearing directly from compressor drive shaft. directly from compressor drive shaft.

�� Free turbine propeller drive Turboprop Free turbine propeller drive Turboprop –– The The shaft on which the free turbine is mounted drives shaft on which the free turbine is mounted drives the propeller through the propeller reduction gear the propeller through the propeller reduction gear system.system.

�� !! A free turbine is independent of compressor A free turbine is independent of compressor drive turbines, and is free to rotate by itself. drive turbines, and is free to rotate by itself.

�� !! Although aircraft turboprop is more Although aircraft turboprop is more complicated and heavier than a turbojet engine complicated and heavier than a turbojet engine at equivalent size and power, it will deliver more at equivalent size and power, it will deliver more thrust at low subsonic airspeeds. However, the thrust at low subsonic airspeeds. However, the advantage decreases as flight speed increases. advantage decreases as flight speed increases.

Types of TurbopropsTypes of Turboprops

�� !! Propulsive efficiency of a turboprop Propulsive efficiency of a turboprop decreases as the airspeed increases, while as in a decreases as the airspeed increases, while as in a turbojet engine propulsive, efficiency increases as turbojet engine propulsive, efficiency increases as airspeed increases. airspeed increases.

�� !! Loss of propulsive efficiency with speed that Loss of propulsive efficiency with speed that becomes a limiting factor at airspeeds above becomes a limiting factor at airspeeds above Mach 0.6 for turboprop aircraft. Mach 0.6 for turboprop aircraft.

Types of TurbopropsTypes of Turboprops

TurboshaftTurboshaft�� Similar to a free turbine propeller drive turboprop Similar to a free turbine propeller drive turboprop

but it drives something other than a propeller, but it drives something other than a propeller, such as the rotor of a helicopter or as an such as the rotor of a helicopter or as an Auxiliary Power Unit in jet airplanes.Auxiliary Power Unit in jet airplanes.

TurboshaftTurboshaft

Turbofan Turbofan �� In principle, a turbofan is much like a turboprop In principle, a turbofan is much like a turboprop

except that the bypass ratio is less. except that the bypass ratio is less.

�� In turbofan, the gearIn turbofan, the gear--driven propeller is replaced driven propeller is replaced by a duct enclosed, axial flow fan with rotating by a duct enclosed, axial flow fan with rotating blades and stationary vains, similar to blades and blades and stationary vains, similar to blades and vanes of the axial flow compressor, just larger.vanes of the axial flow compressor, just larger.

Turbofan Turbofan

Turbofan Turbofan

Turbofan Turbofan

Turbofan Turbofan

Bypass ratioBypass ratio�� ratio of the secondary airflow of airflow to the fan ratio of the secondary airflow of airflow to the fan

or propeller to the primary airflow or airflow to or propeller to the primary airflow or airflow to the basic engine.the basic engine.

2 Main Categories of 2 Main Categories of Bypass EnginesBypass Engines�� High Bypass Ration Engines High Bypass Ration Engines –– Bypass Bypass ratio greater than fiveratio greater than five

2 Main Categories of 2 Main Categories of Bypass EnginesBypass Engines�� Low Bypass Ratio Engine Low Bypass Ratio Engine –– Bypass Bypass ratio less than fiveratio less than five

2 Principal Configurations 2 Principal Configurations of a turbofanof a turbofan�� Forward Fan Forward Fan –– Fan at front of engineFan at front of engine

�� Aft Fan Engine Aft Fan Engine –– Fan at rear of engineFan at rear of engine�� !! The fan produce between 30 to 75% of total The fan produce between 30 to 75% of total

thrust depending on the bypass ratio.thrust depending on the bypass ratio.�� !! Turbofan combines the good operating Turbofan combines the good operating

efficiency and high thrust capability of a efficiency and high thrust capability of a turboprop and the high speed high altitude turboprop and the high speed high altitude capability of a turbojet. capability of a turbojet.

Turbofan Advantage over Turbofan Advantage over TurbopropTurboprop�� Lighter weightLighter weight

�� Unsusceptible to propeller and associated feature Unsusceptible to propeller and associated feature malfunctions.malfunctions.

�� Can attain higher velocities, even up to Can attain higher velocities, even up to supersonic range, with no loss in propulsive supersonic range, with no loss in propulsive efficiency efficiency

Turbofan Advantage over Turbofan Advantage over TurbopropTurboprop�� Can be equipped with afterburnersCan be equipped with afterburners

�� !! Fan section turbofan engine would not Fan section turbofan engine would not decrease in propulsive efficiency and would not decrease in propulsive efficiency and would not stall at supersonic speeds, due to the design of stall at supersonic speeds, due to the design of the inlet ducts which controls the flow of air. the inlet ducts which controls the flow of air. Instead turbofan engine increases in propulsive Instead turbofan engine increases in propulsive efficiency as air velocity increases, due to ram efficiency as air velocity increases, due to ram effect.effect.

�� Lower noise levelLower noise level�� Lower fuel consumptionLower fuel consumption�� Greater thrust at lower airspeedsGreater thrust at lower airspeeds�� Shorter runway neededShorter runway needed

Comparison is based upon engines of equal thrust Comparison is based upon engines of equal thrust output.output.

Turbofan Advantage over Turbofan Advantage over TurbojetTurbojet

Jet Engines with Jet Engines with Afterburners (Reheaters)Afterburners (Reheaters)�� Afterburners are located aft of the normal Afterburners are located aft of the normal

exhaust duct. Provides additional thrust by again exhaust duct. Provides additional thrust by again expanding engine exhaust gases by heat, which expanding engine exhaust gases by heat, which in turn further accelerates the airflow. in turn further accelerates the airflow.

�� !! An engine equipped with an afterburner can An engine equipped with an afterburner can develop 50% or more additional thrust.develop 50% or more additional thrust.

Jet Engines with Jet Engines with Afterburners (reheaters)Afterburners (reheaters)

ThrustThrust�� The force generated through a jet engine comes The force generated through a jet engine comes

from the difference between the momentum of from the difference between the momentum of air leaving the exhaust and the momentum of the air leaving the exhaust and the momentum of the air entering the inlet. When the exit static air entering the inlet. When the exit static pressure of the air exceeds the ambient static pressure of the air exceeds the ambient static pressure an additional thrust force is generated. pressure an additional thrust force is generated.

�� !! Thrust is created from the unbalanced forces Thrust is created from the unbalanced forces and momentum created within then engine itself.and momentum created within then engine itself.

Net Thrust Net Thrust �� Is the thrust that results from the change in Is the thrust that results from the change in

momentum of the mass of air and the fuel that momentum of the mass of air and the fuel that passes through the engine.passes through the engine.

�� Fn = Fn = ∆∆M + (PeM + (Pe--Po)AePo)Ae

�� Fn = (MeFn = (Me--Mo) + (PeMo) + (Pe--Po)AePo)Ae

Gross ThrustGross Thrust�� Is the total thrust developed by an engine which Is the total thrust developed by an engine which does not take into account the momentum of does not take into account the momentum of incoming air, but only the outgoing.incoming air, but only the outgoing.�� !! During ground run where the velocity of the During ground run where the velocity of the aircraft is zero, the net thrust is equal to the aircraft is zero, the net thrust is equal to the gross thrust.gross thrust.�� !! The amount of thrust that an engine The amount of thrust that an engine produces is usually measured when the engine is produces is usually measured when the engine is mounted in a test stand on the ground.mounted in a test stand on the ground.

Reverse ThrustReverse Thrust�� A mechanism used to decrease the momentum, A mechanism used to decrease the momentum,

of air exhaust, which result in a negative total of air exhaust, which result in a negative total change in momentum, thus decreasing the change in momentum, thus decreasing the aircraft speed.aircraft speed.

Reverse ThrustReverse Thrust

Factors Affecting ThrustFactors Affecting Thrust�� At any given throttle setting, engine thrust will At any given throttle setting, engine thrust will

vary as the temperature and pressure of the air vary as the temperature and pressure of the air entering the engine change.entering the engine change.

Factors Affecting ThrustFactors Affecting Thrust�� Jet Nozzle Velocity Jet Nozzle Velocity –– Higher throttle settings Higher throttle settings

incorporates the jet nozzle velocity as a limiting incorporates the jet nozzle velocity as a limiting factor. Gases passing through the converging factor. Gases passing through the converging section of the nozzle will be limited below the section of the nozzle will be limited below the speed of sound. As the exhaust velocity reaches speed of sound. As the exhaust velocity reaches sonic, the nozzle section will be choked, for the sonic, the nozzle section will be choked, for the exhaust duct is incapable of enhancing exhaust exhaust duct is incapable of enhancing exhaust velocities at supersonic range. Unless otherwise velocities at supersonic range. Unless otherwise that the exhaust duct is specially designed to that the exhaust duct is specially designed to handle such speeds.handle such speeds.

�� Air Velocity Air Velocity –– It has been shown that the It has been shown that the variation in the jet nozzle velocity is small at variation in the jet nozzle velocity is small at higher throttle settings, for the nozzle will be higher throttle settings, for the nozzle will be choked. Therefore the difference between the choked. Therefore the difference between the velocity of the incoming air and the outgoing will velocity of the incoming air and the outgoing will be less at higher airplane velocities. As airplane be less at higher airplane velocities. As airplane speed increases thrust goes down.speed increases thrust goes down.

Factors Affecting ThrustFactors Affecting Thrust

Factors Affecting ThrustFactors Affecting Thrust�� Mass Flow Mass Flow –– Most significant variable in the trust Most significant variable in the trust

equations is the mass flow. Mass flow at the equations is the mass flow. Mass flow at the engine is controlled by the fixed engineengine is controlled by the fixed engine--inlet inlet area, unless the engine has a variable inlet area, area, unless the engine has a variable inlet area, the mass flow at any given RPM is determined by the mass flow at any given RPM is determined by the density of air going into the compressor.the density of air going into the compressor.

�� Density Density –– the greater the density the higher the the greater the density the higher the thrust produced.thrust produced.

�� Temperature Temperature –– In free air, a rise in temperature In free air, a rise in temperature will cause the density to decrease. Thus as will cause the density to decrease. Thus as increase in temperature would be a decrease in increase in temperature would be a decrease in thrust.thrust.

�� Pressure Pressure –– The greater the pressure the greater The greater the pressure the greater the density, and so the greater thrust.the density, and so the greater thrust.


�� Altitude effect Altitude effect –– Is a function of density, pressure Is a function of density, pressure and temperature. Which all drops as altitude and temperature. Which all drops as altitude increases, and will decrease more as it reaches increases, and will decrease more as it reaches stratosphere, due to a stagnant temperature.stratosphere, due to a stagnant temperature.

�� !! If only the engine is considered, this makes If only the engine is considered, this makes the stratosphere the optimum altitude for long the stratosphere the optimum altitude for long range cruising at normal speeds.range cruising at normal speeds.


Factors Affecting ThrustFactors Affecting Thrust�� Ram Effect Ram Effect –– To gain ram pressure A/C needs To gain ram pressure A/C needs

more speed, ram effect increases the airflow to more speed, ram effect increases the airflow to the engine, which in turn means more thrust, but the engine, which in turn means more thrust, but an increase in air velocity would cause the thrust an increase in air velocity would cause the thrust to decrease. As the aircraft goes faster eventually to decrease. As the aircraft goes faster eventually becomes ram effect becomes sufficient enough to becomes ram effect becomes sufficient enough to make up for the loss in thrust caused by the make up for the loss in thrust caused by the increase in inlet velocity. Ram also compensates increase in inlet velocity. Ram also compensates for some of the loss thrust due to loss of pressure for some of the loss thrust due to loss of pressure at high altitudes. When the speed becomes high at high altitudes. When the speed becomes high enough, the ram effect will produce an overall enough, the ram effect will produce an overall increase in total thrust. increase in total thrust.


Specific Fuel ConsumptionSpecific Fuel Consumption�� Thrust specific fuel consumption Thrust specific fuel consumption –– The engines The engines

fuel consumption in lbs per hour divided by net fuel consumption in lbs per hour divided by net thrust.thrust.

�� The amount of fuel required to produce one The amount of fuel required to produce one pound of thrust.pound of thrust.

�� TSFC = TSFC = Wf Wf FnFn

�� Where: TSFC = Thrust Specific Fuel ConsumptionWhere: TSFC = Thrust Specific Fuel ConsumptionWT = Fuel flowWT = Fuel flowFn = Net thrustFn = Net thrust

Specific Fuel ConsumptionSpecific Fuel Consumption

Airborne Measuring Airborne Measuring DevicesDevices

FAN SPEEDCORE ENGINE

SPEEDENGINE

PRESSURE RATIOEXHAUST GAS TEMPERATURE

�� Tachometer Tachometer –– Based on the fact that thrust is Based on the fact that thrust is directly proportional to the engine RPM.directly proportional to the engine RPM.

�� Exhaust Gas Temperature Exhaust Gas Temperature –– System used in System used in measuring Engine exhaust temperature for measuring Engine exhaust temperature for engine operating limitations.engine operating limitations.

�� Engine Pressure Ratio Engine Pressure Ratio –– is the turbine discharge is the turbine discharge total pressure divided by the total pressure at the total pressure divided by the total pressure at the engine inlet. Most frequently used parameter.engine inlet. Most frequently used parameter.

Airborne Measuring Airborne Measuring DevicesDevices

Subsonic, Sonic, Subsonic, Sonic, Supersonic Gas FlowSupersonic Gas Flow�� SubsonicSubsonic-- Free stream velocity is ranged below Free stream velocity is ranged below

the speed at sound.the speed at sound.

�� SonicSonic-- Mach 1.0 or speed equivalent to the speed Mach 1.0 or speed equivalent to the speed of sound.of sound.

�� SupersonicSupersonic-- speeds exceeding the speed of speeds exceeding the speed of sound.sound.

�� Speed of sound is a function at the air temp.Speed of sound is a function at the air temp.

Gas GeneratorGas Generator�� Used to describe all gas producing section or Used to describe all gas producing section or

component of a gas turbine engine. Excludes component of a gas turbine engine. Excludes ducts, shafts, reduction gears.ducts, shafts, reduction gears.

Components of a Gas Components of a Gas Turbine EngineTurbine Engine�� Inlet DuctInlet Duct�� CompressorCompressor�� Combustion ChamberCombustion Chamber�� TurbineTurbine�� Exit NozzleExit Nozzle

Gas Turbine Engine Gas Turbine Engine ComponentsComponents�� Air inlet ductAir inlet duct

–– Turbojet inlet ductTurbojet inlet duct–– Turboprop air inlet and reduction gearingTurboprop air inlet and reduction gearing–– Turbofan air inlet and Fan sectionTurbofan air inlet and Fan section

Gas Turbine Engine Inlet Gas Turbine Engine Inlet DuctDuct

Turbofan/Turbojet Inlet Turbofan/Turbojet Inlet Duct Duct –– SubsonicSubsonic

Turbofan/Turbojet Inlet Turbofan/Turbojet Inlet Duct Duct –– SupersonicSupersonic



Turboprop Inlet DuctTurboprop Inlet Duct

Turboprop Inlet DuctTurboprop Inlet Duct

Components of a Gas Components of a Gas Turbine EngineTurbine Engine�� CompressorCompressor

An integral component of a gas turbine engine, An integral component of a gas turbine engine, whose main objective is to supply compressed air for whose main objective is to supply compressed air for combustion in the combustion chamber.combustion in the combustion chamber.

Components of a Gas Components of a Gas Turbine EngineTurbine Engine

�� Compressor ModuleCompressor Module

Gas Turbine Engine Gas Turbine Engine ComponentsComponents�� Compressor ModuleCompressor Module�� ----compressor drive shaftcompressor drive shaft�� ----compressor bladescompressor blades�� ----rotor bladesrotor blades�� ----stator bladesstator blades�� ----compressor disc or drumscompressor disc or drums

Components of a Gas Components of a Gas Turbine EngineTurbine Engine�� 3 Types of Compressors3 Types of Compressors

�� Centrifugal Flow Compressor Centrifugal Flow Compressor –– 1st type developed1st type developed�� Axial Flow Compressor Axial Flow Compressor –– type most widely usedtype most widely used�� ---- Single SpoolSingle Spool�� ---- Dual SpoolDual Spool�� CentrifugalCentrifugal--Axial Flow CompressorAxial Flow Compressor

Gas GeneratorGas Generator

Axial Flow Compressor Centrifugal Flow Compressor

Gas Turbine Engine Gas Turbine Engine ComponentsComponents

Gas Turbine Engine Gas Turbine Engine ComponentsComponents

ROTOR SHAFT

DISC

REAR ROTATING AIR SEAL

HP COMPRESSOR ROTOR DESIGN

Gas Turbine Engine Gas Turbine Engine ComponentsComponents�� Diffuser SectionDiffuser Section

FAN FRAME

LP SHAFT

HP SHAFT

TURBINE FRAME

Gas Turbine Engine Gas Turbine Engine ComponentsComponents�� Fuel Manifolds and NozzlesFuel Manifolds and Nozzles

--swirl typeswirl typeor multiple or multiple typetype

COMBUSTION CASE

COMBUSTION CASE FRONT FLANGE

COMBUSTION CASE REAR FLANGE

HP TURBINE SECTION

COMBUSTION CHAMBER

Gas Turbine Engine Gas Turbine Engine ComponentsComponents�� Combustion chambersCombustion chambers

–– Can typeCan type


–– Annular typeAnnular type


–– CanCan--annular typeannular type

Components of a Gas Components of a Gas Turbine EngineTurbine Engine�� TurbineTurbine

Components of a Gas Components of a Gas Turbine EngineTurbine Engine�� Exit NozzleExit Nozzle

Gas Turbine Engine Gas Turbine Engine ComponentsComponents�� NozzleNozzle–– Fixed geometryFixed geometry

Gas Turbine Engine Gas Turbine Engine ComponentsComponents�� NozzleNozzle–– VariableVariablegeometrygeometry

Chapter 2Chapter 2Engine Systems of Industry’s Engine Systems of Industry’s

Current Engines Current Engines

Engine ATA ChaptersEngine ATA Chapters�� 70 70 –– Engine Standard PracticesEngine Standard Practices�� 71 71 –– PowerplantPowerplant�� 72 72 –– EngineEngine�� 73 73 –– Engine Fuel and ControlEngine Fuel and Control�� 74 74 –– Engine Ignition SystemEngine Ignition System�� 75 75 –– Engine Air SystemEngine Air System�� 76 76 –– Engine ControlsEngine Controls�� 77 77 –– Engine Indicating SystemEngine Indicating System�� 78 78 –– Engine Exhaust SystemEngine Exhaust System�� 79 79 –– Engine Lubricating SystemEngine Lubricating System�� 80 80 –– Engine Starting SystemEngine Starting System

ATA 73 ATA 73 –– Engine Fuel and Engine Fuel and ControlControl�� The engine fuel and control system provides a The engine fuel and control system provides a

means of supplying and controlling the flow of means of supplying and controlling the flow of fuel going to the engine combustion chambers to fuel going to the engine combustion chambers to be used for combustion.be used for combustion.

�� Boost PumpsBoost Pumps�� FiltersFilters�� Main Fuel PumpMain Fuel Pump�� Fuel control unitFuel control unit�� Fuel shut off valveFuel shut off valve�� Staging valve (for fuel spray nozzle in duplex Staging valve (for fuel spray nozzle in duplex

type)type)�� Fuel ManifoldsFuel Manifolds�� Fuel Spray NozzleFuel Spray Nozzle

General Parts of Fuel General Parts of Fuel SystemSystem

�� Also called the low pressure pump the function of Also called the low pressure pump the function of the Boost pump is to suck the fuel from the fuel the Boost pump is to suck the fuel from the fuel line and supply it to the main engine fuel pump line and supply it to the main engine fuel pump and to the engine fuel control unit. and to the engine fuel control unit. �� The boost pump is necessary for the engine fuel The boost pump is necessary for the engine fuel system operation, as it pressurizes the fuel to the system operation, as it pressurizes the fuel to the right amount before it enters the main fuel pump.right amount before it enters the main fuel pump.�� Without the boost pump, the main fuel pump Without the boost pump, the main fuel pump would experience cavitation and would not be would experience cavitation and would not be able to pressurize the fuel to the required able to pressurize the fuel to the required amount.amount.

Boost PumpsBoost Pumps

Main Fuel PumpMain Fuel Pump�� The main fuel pump receives the fuel from the The main fuel pump receives the fuel from the

low pressure fuel pump and pressurizes it even low pressure fuel pump and pressurizes it even further and supplies it to the engine fuel control further and supplies it to the engine fuel control unit. unit.

�� The main fuel pump provides a fuel pressure The main fuel pump provides a fuel pressure greater than what is required by the engine for greater than what is required by the engine for proper operation. proper operation.

CFM56CFM56--5B Fuel Pumps5B Fuel Pumps

FUEL PUMP AND FILTER ASSEMBLY

FUEL PUMP AND FILTER ASSEMBLY

FiltersFilters�� A fuel filter is a requirement in any fuel system of A fuel filter is a requirement in any fuel system of

any heat engine that uses liquid fuel. The fuel any heat engine that uses liquid fuel. The fuel filter provides a means of protection of the filter provides a means of protection of the engine fuel components from any foreign object engine fuel components from any foreign object that may be caught inside its mechanisms.that may be caught inside its mechanisms.

Fuel FiltersFuel Filters

�� The engine fuel control unit receives the overly The engine fuel control unit receives the overly pressurized fuel form the main fuel pump. pressurized fuel form the main fuel pump. �� The fuel control unit meters the right amount of The fuel control unit meters the right amount of fuel that is needed for proper operation of the fuel that is needed for proper operation of the engine and supplies it to the engine combustion engine and supplies it to the engine combustion chamber through the fuel manifolds and spray chamber through the fuel manifolds and spray nozzle.nozzle.�� The metering of the fuel is based on the actual The metering of the fuel is based on the actual conditions at the time of the operation of the conditions at the time of the operation of the engine. engine. �� Ambient conditionsAmbient conditions�� Actual rotor speedsActual rotor speeds�� Compressor working conditionCompressor working condition

Fuel Control UnitFuel Control Unit

Fuel Shut Off ValveFuel Shut Off Valve�� The fuel shut off valve is a part of the engine fuel The fuel shut off valve is a part of the engine fuel

system that shuts off or allows entry of the fuel system that shuts off or allows entry of the fuel from the aircraft tanks to the combustion from the aircraft tanks to the combustion chamber. chamber.

�� Usually is an integral part of other engine Usually is an integral part of other engine components and is directly controlled from the components and is directly controlled from the cockpit.cockpit.

CFM56CFM56--5B Fuel Control 5B Fuel Control UnitUnit

FUEL CONTROL UNIT

FUEL CONTROL UNIT

CFM56CFM56--5B Fuel Control 5B Fuel Control Unit ProcessUnit Process

FCU

FUEL CONTROL UNIT PURPOSES

Staging ValveStaging Valve�� Used in gas turbine engines that utilizes more Used in gas turbine engines that utilizes more

than one fuel flow for combustion. Separates the than one fuel flow for combustion. Separates the fuel flow coming from the fuel control unit into a fuel flow coming from the fuel control unit into a primary and secondary flow and supplies it to the primary and secondary flow and supplies it to the fuel manifolds and to the fuel nozzle.fuel manifolds and to the fuel nozzle.

CFM56CFM56--5B Staging Valve5B Staging Valve

STAGING VALVE

Fuel Manifolds and Fuel Manifolds and NozzlesNozzles�� Fuel is introduced into the air stream at the front Fuel is introduced into the air stream at the front

of the burners in spray form By a manifold of the burners in spray form By a manifold system to Nozzle mounted in the burner cans. system to Nozzle mounted in the burner cans. The most common type of Nozzle employs a The most common type of Nozzle employs a pressure atomizing principle w/c ensures the pressure atomizing principle w/c ensures the uniform distribution of fine particles. uniform distribution of fine particles.

Fuel ManifoldsFuel Manifolds�� The fuel manifolds are passages of the metered The fuel manifolds are passages of the metered

fuel that are directly installed around the fuel that are directly installed around the combustion chamber. The fuel manifold provides combustion chamber. The fuel manifold provides metered fuel passage going to the engine fuel metered fuel passage going to the engine fuel nozzle.nozzle.

CFM56CFM56--5B Fuel Manifold5B Fuel Manifold

Fuel Spray NozzleFuel Spray Nozzle�� The Spray Nozzle is the last component that the The Spray Nozzle is the last component that the

fuel will pass through before going into the fuel will pass through before going into the combustion chamber.combustion chamber.

�� The main purpose of the fuel spray nozzle is to The main purpose of the fuel spray nozzle is to atomize the metered fuel as is goes into the atomize the metered fuel as is goes into the combustion chamber. combustion chamber.

CFM56CFM56--5B Fuel Spray 5B Fuel Spray NozzleNozzle

CFM56CFM56--5B Fuel Spray 5B Fuel Spray NozzleNozzle

ATA 74 ATA 74 –– Engine Ignition Engine Ignition SystemSystem�� The purpose of the ignition system is to ignite the The purpose of the ignition system is to ignite the

air/fuel mixture within the combustion chamber. air/fuel mixture within the combustion chamber. An FAA certified gas turbine engine requires a An FAA certified gas turbine engine requires a dual ignition system, consisting of two dual ignition system, consisting of two independent systems.independent systems.

General Parts of the General Parts of the ignition Systemignition System�� Ignition ExciterIgnition Exciter�� Igniter LeadsIgniter Leads�� Igniter PlugsIgniter Plugs

System Operation and System Operation and NomenclatureNomenclature�� A current is supplied to the ignition exciters A current is supplied to the ignition exciters

and transformed into high voltage pulses. and transformed into high voltage pulses. These pulses are sent, through ignition These pulses are sent, through ignition leads, to the tip of the igniter plugs, leads, to the tip of the igniter plugs, producing sparks.producing sparks.

�� The ignition system provides the means of The ignition system provides the means of initiating combustion for engine starting or initiating combustion for engine starting or inin--flight relighting and maintaining flight relighting and maintaining combustion in adverse conditions.combustion in adverse conditions.

System Operation and System Operation and NomenclatureNomenclature�� The ignition system utilizes an ignition power The ignition system utilizes an ignition power

supply, high tension distribution system and supply, high tension distribution system and engine ignition control system to obtain a spark to engine ignition control system to obtain a spark to ignite the fuel.ignite the fuel.

�� The power supply system comprises two high The power supply system comprises two high energy (H.E) ignition units which are supplied energy (H.E) ignition units which are supplied with electrical power from the aircraft system via with electrical power from the aircraft system via the appropriate branch of the engine electrical the appropriate branch of the engine electrical harness. The ignition units step up the voltage harness. The ignition units step up the voltage and supply high tension power to the distribution and supply high tension power to the distribution system.system.

System Operation and System Operation and NomenclatureNomenclature�� The high tension distribution system comprises The high tension distribution system comprises

two H.E. igniter plugs and two H.E. igniter leads. two H.E. igniter plugs and two H.E. igniter leads. The leads convey the high tension electrical The leads convey the high tension electrical supply from the ignition units to the igniter plugs supply from the ignition units to the igniter plugs where it is dissipated in the form of an intense where it is dissipated in the form of an intense spark.spark.

�� The engine ignition control is provided by the The engine ignition control is provided by the engine start switch and ignition selection switch. engine start switch and ignition selection switch. With these switches properly positioned, electrical With these switches properly positioned, electrical power is supplied to the exciters for use in engine power is supplied to the exciters for use in engine ignition.ignition.

SPARK IGNITER (2) SPARK IGNITER (2)

IGNITION LEAD ASSEMBLY (2)

IGNITIOIN GENERAL

CFM56CFM56--5B Engine Ignition System5B Engine Ignition System

Ignition ExcitersIgnition Exciters

�� The ignition exciters transform the low voltage The ignition exciters transform the low voltage input from an external source into repeated high input from an external source into repeated high voltage output pulses. The high voltage output voltage output pulses. The high voltage output reaches to as much as 20000Vreaches to as much as 20000V

IGNITION LEADS

ELECTRICAL CONNECTOR SYSTEM B

ELECTRICAL CONNECTOR SYSTEM A

EXCITERS

IGNITION EXCITERS

CFM56CFM56--5B Ignition 5B Ignition ExcitersExciters

Ignition Distribution Ignition Distribution SystemSystem�� The purpose of the distribution system is to The purpose of the distribution system is to

transmit the electrical energy delivered by the transmit the electrical energy delivered by the ignition exciters to produce sparks inside the ignition exciters to produce sparks inside the combustor.combustor.

CFM56CFM56--5B Ignition 5B Ignition Distribution SystemDistribution System

ATA 75 ATA 75 –– Engine Air Engine Air SystemSystem�� The engine air system is comprised of the The engine air system is comprised of the

Internal Cooling and Sealing Air system, Internal Cooling and Sealing Air system, Accessory Cooling System, Compressor Bleed Accessory Cooling System, Compressor Bleed control system which includes the environmental control system which includes the environmental control system bleed.control system bleed.

Internal and Accessory Internal and Accessory Cooling SystemCooling System�� To cool the engine mounted accessory units and To cool the engine mounted accessory units and

maintain undermaintain under--cowl temperatures at an cowl temperatures at an acceptable level, calibrated airflows are provided acceptable level, calibrated airflows are provided around the propulsion unit.around the propulsion unit.

RB211RB211--535E4 Accessory 535E4 Accessory Cooling SystemCooling System

AFT MOUNT

COOLING AIR REAR INLETS

TURBINE CASE COOLING AIR INLET

OUTLET AND PRESSURE RELIEF DOORAIR OUTLETINLET COWL

PRESSURE RELIEF DOOR

INLET COWL PRESSURE RELIEF DOOR

FORWARD MOUNT

CFM56CFM56--5B Internal Cooling 5B Internal Cooling SystemSystem--Parasite AirParasite Air

Compressor Bleed Control Compressor Bleed Control SystemSystem�� To maintain a stable airflow through the To maintain a stable airflow through the

compressor section during certain transient and compressor section during certain transient and steady running conditions, a percentage of air is steady running conditions, a percentage of air is vented from the compressors through bleed vented from the compressors through bleed valves, usually these bleed valves discharge to valves, usually these bleed valves discharge to the LP compressor fan outlet.the LP compressor fan outlet.

1 – MASTER BLEED VALVE2 – VARIABLE BLEED VALVE3 – INTER CONNECTING SHAFT4 – POSITION SENSOR5 – GEAR MOTOR ASSEMBLY6 – STOP MECHANISM ASSEMBLY7 – MAIN FLEXIBLE SHAFT8 – FEEDBACK ROD

CFM56CFM56--5B Compressor 5B Compressor Bleed Control SystemBleed Control System

ATA 76 ATA 76 –– Engine Control Engine Control SystemSystem�� The engine control system provides the means The engine control system provides the means for controlling fuel and ignition for starting, for controlling fuel and ignition for starting, operating and shutting down the engines, and for operating and shutting down the engines, and for controlling engine forward and reverse thrust. controlling engine forward and reverse thrust. Controlling the forward and reverse thrust is Controlling the forward and reverse thrust is accomplished by movement of the forward and accomplished by movement of the forward and reverse thrust levers in the flight compartment. reverse thrust levers in the flight compartment. This movement is transmitted through the This movement is transmitted through the airplane and engine mounted cables to the airplane and engine mounted cables to the engine fuel control unit.engine fuel control unit.

Components of the Components of the Engine Control SystemEngine Control System�� Thrust lever assemblyThrust lever assembly�� Control cablesControl cables

Thrust Lever AssemblyThrust Lever Assembly�� The thrust lever assembly is located in the control The thrust lever assembly is located in the control

stand on the flight compartment. The assembly stand on the flight compartment. The assembly contains forward and reverse thrust levers.contains forward and reverse thrust levers.

Thrust Lever AssemblyThrust Lever Assembly

THRUST CONTROL LEVERS

THRUST REVERSE LEVER

FORWARD THRUST LEVER

CONTROL CALBE

FUEL CONTROL UNIT

RB211RB211--535E4 535E4 Engine Control SystemEngine Control System

A320 Engine indicatingA320 Engine indicating

ATA 77 ATA 77 –– Engine Engine indicating Systemindicating System�� The engine indicating system provides a means The engine indicating system provides a means

of monitoring the engine condition and its of monitoring the engine condition and its performance. performance.

Common Indicating Common Indicating ParametersParameters�� Engine Pressure RatioEngine Pressure Ratio�� Shaft Rotor SpeedShaft Rotor Speed�� Exhaust Gas TemperatureExhaust Gas Temperature�� Engine Vibration MonitorEngine Vibration Monitor�� Fuel FlowFuel Flow�� Oil PressureOil Pressure

Engine Pressure RatioEngine Pressure Ratio�� Also known as the EPR indicating system, Also known as the EPR indicating system,

compares the exit pressure to the inlet pressure compares the exit pressure to the inlet pressure and sends its value to an indicator located at the and sends its value to an indicator located at the cockpit.cockpit.

Shaft Rotor SpeedShaft Rotor Speed�� Denoted by the letter N, is the ratio of the actual Denoted by the letter N, is the ratio of the actual

engine speed and the maximum speed that the engine speed and the maximum speed that the engine can attain at a given condition. engine can attain at a given condition. Sometimes referred to as %RPM since it indicates Sometimes referred to as %RPM since it indicates the percentage of maximum rotor rotation.the percentage of maximum rotor rotation.

Exhaust Gas TemperatureExhaust Gas Temperature�� Known also the as EGT, this parameters is used Known also the as EGT, this parameters is used

to monitor the engine exhaust temperature. The to monitor the engine exhaust temperature. The engine just as any machine has a maximum engine just as any machine has a maximum operating temperature, if this temperature is operating temperature, if this temperature is exceeded, serious damage to the engine can exceeded, serious damage to the engine can occur. Thus the EGT is one of the most important occur. Thus the EGT is one of the most important engine indicating parameter.engine indicating parameter.

�� ECAM or EICASECAM or EICAS

A320 Engine indicating A320 Engine indicating SystemSystem

ATA 78 ATA 78 –– Engine Exhaust Engine Exhaust SystemSystem�� The cold stream and hot stream gases are The cold stream and hot stream gases are

discharged to the atmosphere through the engine discharged to the atmosphere through the engine exhaust system, at a velocity and in the required exhaust system, at a velocity and in the required direction to provide the resultant thrust.direction to provide the resultant thrust.

CFM56CFM56--5B Engine 5B Engine Exhaust SystemExhaust System

ATA 79 ATA 79 –– Engine Engine Lubricating SystemLubricating System�� The oil system is of the selfThe oil system is of the self--contained, full flow contained, full flow

rere--circulatory type and provides lubrication and circulatory type and provides lubrication and cooling oil to the engine bearings, gears and cooling oil to the engine bearings, gears and splines.splines.

Common Components of Common Components of oil Systemoil System�� Oil tankOil tank�� Pressure PumpPressure Pump�� Scavenge PumpScavenge Pump�� FiltersFilters

CFM56CFM56--5B Engine 5B Engine Lubricating SystemLubricating System


Common Components of Common Components of oil Systemoil System�� Oil tankOil tank�� Pressure PumpPressure Pump�� Scavenge PumpScavenge Pump�� FiltersFilters

CFM56CFM56--5B Components of 5B Components of oil Systemoil System



ATA 80 ATA 80 –– Engine Starting Engine Starting SystemSystem�� The engine starting system supplies the input to The engine starting system supplies the input to

turn the engine high pressure (HP) compressor turn the engine high pressure (HP) compressor rotor to a speed at which engine lightrotor to a speed at which engine light--up can up can occur. The system is used for ground starts, and occur. The system is used for ground starts, and can also be used for incan also be used for in--flight starts.flight starts.

Engine Starting SystemEngine Starting System�� The start system includes the engineThe start system includes the engine--mounted mounted

components that follow: components that follow: (1) A pneumatic starter is installed on the (1) A pneumatic starter is installed on the

forward face of the highforward face of the high--speed (HS) speed (HS) external gearbox.external gearbox.

(2) A starter control valve is installed on the (2) A starter control valve is installed on the lower left side of the low pressure (LP) lower left side of the low pressure (LP) compressor (fan) case.compressor (fan) case.

(3) The related air ducting and electrical (3) The related air ducting and electrical wiring.wiring.

Types of StartersTypes of Starters�� Direct electric motorDirect electric motor�� Air Turbine or Pneumatic StarterAir Turbine or Pneumatic Starter�� CombustionCombustion�� HydraulicHydraulic

CFM56CFM56--5B Pneumatic 5B Pneumatic StarterStarter

StartingStarting�� The HP compressor rotor assembly is turned by The HP compressor rotor assembly is turned by

the starter through the HS external gearbox. The the starter through the HS external gearbox. The starter is a pneumatically driven motor, starter is a pneumatically driven motor, connected by ducts to the bleed air system of the connected by ducts to the bleed air system of the aircraft. Air for the starter can be supplied by a aircraft. Air for the starter can be supplied by a ground supply, the Auxiliary Power Unit (APU) or ground supply, the Auxiliary Power Unit (APU) or from the other engine.from the other engine.

Chapter 3Chapter 3Innovations in Gas Turbine Innovations in Gas Turbine

Propulsion Propulsion

Future TechnologyFuture Technology�� MTU Active Core ConceptMTU Active Core Concept�� CFM Technology Advancement CFM Technology Advancement ProgramProgram�� IAE Select One ProgramIAE Select One Program�� GE Advanced Turbo Fan EngineGE Advanced Turbo Fan Engine�� P&W Geared Turbo FanP&W Geared Turbo Fan

MTU MTU Active Core ProgramActive Core Program

Overview of Active Core Overview of Active Core ProgramProgram�� NEWAC has set forth its goals of developing for a NEWAC has set forth its goals of developing for a

reduction of 6% in CO2 emissions and 16% in NOx reduction of 6% in CO2 emissions and 16% in NOx emissions. In order to reach new goals, four major emissions. In order to reach new goals, four major core concepts are being evaluated and additional core concepts are being evaluated and additional research is performed in the development of research is performed in the development of improved combustors. improved combustors.

�� In order to meet the ACARE 2020 objectives, strong In order to meet the ACARE 2020 objectives, strong improvements on engine component efficiencies are improvements on engine component efficiencies are required in addition to new engine architectures. required in addition to new engine architectures. The four core concepts depicted are the following; The four core concepts depicted are the following;

MTU Active Core ProgramMTU Active Core Program�� 1. Intercooled Core1. Intercooled Core�� 2. Intercooled Recuperated Core2. Intercooled Recuperated Core�� 3. Flow Controlled Core3. Flow Controlled Core�� 4. Active Core 4. Active Core

Intercooled CoreIntercooled Core

�� The introduction of an intercooler to a core configuration allows for a The introduction of an intercooler to a core configuration allows for a very high overall pressure ratios. It refuces the compression work for very high overall pressure ratios. It refuces the compression work for such cycles and improves fuel burn.such cycles and improves fuel burn.�� The concept developed in this design is the high Overall Pressure The concept developed in this design is the high Overall Pressure Ratio intercooled turbofan engine, which uses part of the bypass duct Ratio intercooled turbofan engine, which uses part of the bypass duct airflow for intercooling. Intercooling reduces the work required to airflow for intercooling. Intercooling reduces the work required to achieve a given OPR, or enables OPR to be increased for the same achieve a given OPR, or enables OPR to be increased for the same work. This means that the combustor temperature rise is bigger for a work. This means that the combustor temperature rise is bigger for a given Turbine Air Temperature.given Turbine Air Temperature.

Typical Intercooled Typical Intercooled EngineEngine

Intercooler Modules Intercooler Modules around Engine Corearound Engine Core

Intercooled Recuperated Intercooled Recuperated CoreCore

�� This concept exploits the heat of the engine exhaust gas and This concept exploits the heat of the engine exhaust gas and maximizes the heat pick up capacity of the combustor inlet air maximizes the heat pick up capacity of the combustor inlet air by intercooling in front of the HP compressorby intercooling in front of the HP compressor

�� The IRA cycle already will use significant benefits from a The IRA cycle already will use significant benefits from a further increase in propulsive and thermal efficiency with a further increase in propulsive and thermal efficiency with a potential of up to 20% fuel consumption/CO2 emission potential of up to 20% fuel consumption/CO2 emission reductionreduction

Flow Controlled CoreFlow Controlled Core

�� High BPR direct driven turbofan engines require a compact HP High BPR direct driven turbofan engines require a compact HP compressor with very high pressure ratio which has to compensate compressor with very high pressure ratio which has to compensate for the low booster presure ratio. Therefore, flow control technologies for the low booster presure ratio. Therefore, flow control technologies are being investigated, which help in the specific field of very high are being investigated, which help in the specific field of very high aerodynamically loaded HP compressors to strongly increase aerodynamically loaded HP compressors to strongly increase efficiency and stall margin.efficiency and stall margin.�� The strategy is based on the implementation of innovative concepts The strategy is based on the implementation of innovative concepts capable of local contraol of the compressor flow field. The optimized capable of local contraol of the compressor flow field. The optimized design of the compressor in association with the integration of these design of the compressor in association with the integration of these aeroaero--oriented technologies leads to a global benefit. The flow oriented technologies leads to a global benefit. The flow controlled core can also be applied to more conventional high Bypass controlled core can also be applied to more conventional high Bypass RatiosRatios

Commercial Fan MotorsCommercial Fan MotorsTechnology Enhancement Technology Enhancement

ProgramProgram

Commercial Fan MotorsCommercial Fan Motors�� Tech Insertion ProgramTech Insertion Program�� Leap 56 ProgramLeap 56 Program�� LeapLeap--XX�� Unducted Fan Unducted Fan

Commercial Fan MotorsCommercial Fan MotorsTechnology Insertion Program for Technology Insertion Program for

CFM56CFM56--5B & 5B & --7B7B

Tech Insertion ProgramTech Insertion Program

Data from CFM

Tech InsertionTech Insertion�� Tech Insertion is a design Tech Insertion is a design improvement for the current CFM56improvement for the current CFM56--5B and 7B Models.5B and 7B Models.

Data from CFM

Tech Insertion Design Tech Insertion Design CriteriaCriteria�� RequirementsRequirements

oo Non Tech Insertion engines can be intermixed with Tech Non Tech Insertion engines can be intermixed with Tech insertion engines on the same ACinsertion engines on the same AC

oo Transparent operability for the pilotTransparent operability for the pilotoo Preserve asset value for both fleet configurationsPreserve asset value for both fleet configurations

�� EffectsEffectsoo Maintain the same engine architechtureMaintain the same engine architechtureoo Fuel Burn and Maintenance Cost optimizationFuel Burn and Maintenance Cost optimization

Data from CFM

Tech Insertion Customer Tech Insertion Customer BenefitsBenefits�� Reduced Maintenance Cost: 4%Reduced Maintenance Cost: 4%--12% improvement12% improvement

oo Increased time on wing (due to higher EGT MarginIncreased time on wing (due to higher EGT Marginoo Fewer shop visits (due to longer time on wing)Fewer shop visits (due to longer time on wing)oo Reduced performance deterioration rate (improved aerodynamic design Reduced performance deterioration rate (improved aerodynamic design

of HPC and HPT)of HPC and HPT)oo No impact on shop visit costNo impact on shop visit costoo Enhanced component durabilityEnhanced component durability

�� Reduced Fuel BurnReduced Fuel Burnoo Specific Fuel Consumption SFC improved ~0.5% at cruiseSpecific Fuel Consumption SFC improved ~0.5% at cruiseoo SFC improved up to 1% over life cycle due to reduced deteriorationSFC improved up to 1% over life cycle due to reduced deterioration

�� Reduced Emmisions: Nox reduced by 15Reduced Emmisions: Nox reduced by 15--20%20%

Data from CFM

New High Pressure New High Pressure Compressor BladesCompressor Blades

�� Design Features:Design Features:oo New Blade aero designNew Blade aero designoo Improved stage loadingImproved stage loading

�� BenefitsBenefitsoo Improved EGT MarginsImproved EGT Marginsoo Lower Fuel BurnLower Fuel Burn New Aerodynamics in Compressor BladesNew Aerodynamics in Compressor Blades

Data from CFM

New High Pressure New High Pressure Compressor BladesCompressor Blades

�� Design Features:Design Features:oo New Blade aero designNew Blade aero designoo Improved stage loadingImproved stage loading

�� BenefitsBenefitsoo Improved EGT MarginsImproved EGT Marginsoo Lower Fuel BurnLower Fuel Burn

Advanced analytical design technique helped Advanced analytical design technique helped improved combustor coolingimproved combustor cooling

Data from CFM

Advanced Tech56 Low Advanced Tech56 Low Shock Blade DesignShock Blade Design

�� Design Features:Design Features:oo Low Shock airfoil contourLow Shock airfoil contouroo Improved coolingImproved cooling

�� Benefits:Benefits:oo Improved performanceImproved performanceoo Lower Fuel BurnLower Fuel Burnoo Longer time on wingLonger time on wingoo Improved durabilityImproved durabilityoo Reduced interaction losses Reduced interaction losses

between high and low between high and low pressure turbinespressure turbines

Blade contour improves performance Blade contour improves performance

Data from CFM

Most Durable Low Most Durable Low Pressure TurbinePressure Turbine

�� Design Features:Design Features:oo Advanced CoatingsAdvanced Coatingsoo Improved coolingImproved cooling

�� Benefits:Benefits:oo Improved durabilityImproved durabilityoo Lower Scrap rate Lower Scrap rate oo Fewer repairsFewer repairs

Blade contour improves performance Blade contour improves performance

Data from CFM

Technology InsertionTechnology Insertion

Data from CFM

Commercial Fan MotorsCommercial Fan MotorsCFM56CFM56--5B & 7B Technology 5B & 7B Technology

InsertionInsertion

Tech Insertion Program Tech Insertion Program Current StatusCurrent Status�� CompletedCompleted�� Engines with Tech Insertion already in Engines with Tech Insertion already in Service Since October 2007Service Since October 2007�� Applicability; A320 Family and B737Applicability; A320 Family and B737

Commercial Fan MotorsCommercial Fan MotorsLeap 56 ProgramLeap 56 Program

Leading Edge Aviation Leading Edge Aviation PropulsionPropulsion�� LEAP: fundamental technology work for the futureLEAP: fundamental technology work for the future�� Through the LEAP56 (Leading Edge Aviation Propulsion) Through the LEAP56 (Leading Edge Aviation Propulsion) program, CFM is laying a technology foundation that will program, CFM is laying a technology foundation that will position our engine family for future singleposition our engine family for future single--aisle aircraft. aisle aircraft.

Our engineers have developed a list of basic engine design Our engineers have developed a list of basic engine design technologies to be evaluated. These include sophisticated technologies to be evaluated. These include sophisticated composite materials along with nextcomposite materials along with next--generation 3generation 3--D D aerodynamics and a lowaerodynamics and a low--emissions combustor. emissions combustor.

Data from CFM

Commercial Fan MotorsCommercial Fan MotorsLeapLeap--X ProgramX Program

International Aero International Aero EnginesEngines

V2500 Select OneV2500 Select One

Select One UpgradeSelect One Upgrade�� Select One is an upgrade for the current Select One is an upgrade for the current V2500 engineV2500 engine

�� Select One is a comprehensive HP system Select One is a comprehensive HP system upgradeupgrade

�� Select One is to enter into service on the Select One is to enter into service on the third Quarter of 2008 on A320 Family third Quarter of 2008 on A320 Family applicationapplication

Select One UpgradeSelect One Upgrade�� Select One is an upgrade for the current Select One is an upgrade for the current V2500 engineV2500 engine

�� Select One is a comprehensive HP system Select One is a comprehensive HP system upgradeupgrade

�� Select One is to enter into service on the Select One is to enter into service on the third Quarter of 2008 on A320 Family third Quarter of 2008 on A320 Family applicationapplication

Select One EnhancementsSelect One Enhancements�� 1% Reduced Fuel Burn1% Reduced Fuel Burn�� 20% Time on wing improvement20% Time on wing improvement�� Additional 12 Deg C EGT MarginAdditional 12 Deg C EGT Margin�� 40% Fewer miscellaneous shop visits40% Fewer miscellaneous shop visits�� Maintains the V2500 as overall Maintains the V2500 as overall environmental leaderenvironmental leader�� Minimum cost retrofitMinimum cost retrofit

Design ImprovementsDesign Improvements

�� HP Compressor System UpgradeHP Compressor System Upgrade�� HT Turbine System UpgradeHT Turbine System Upgrade�� LP Turbine System UpgradeLP Turbine System Upgrade

HP Compressor UpgradeHP Compressor Upgrade�� Aerodynamic ModificationsAerodynamic Modifications�� Mechanical modifications Mechanical modifications �� Elliptical leading edge and improved Elliptical leading edge and improved surface finish of HPC bladessurface finish of HPC blades

HP Turbine UpgradeHP Turbine Upgrade�� Redistributed Cooling and Minor Restagger of 1Redistributed Cooling and Minor Restagger of 1stst Stage HP Nozzle Stage HP Nozzle Guide VanesGuide Vanes

--Increased LifeIncreased Life--Optimum Cycle PerformanceOptimum Cycle Performance

�� Add film cooling, state of the art coating and Internal cooling Add film cooling, state of the art coating and Internal cooling changes of the HPT Blades Stage 1changes of the HPT Blades Stage 1--Increased LifeIncreased Life

�� Additional Platform cooling for 2Additional Platform cooling for 2ndnd Stage HP Nozzle Guide VanesStage HP Nozzle Guide Vanes--Increased LifeIncreased Life

�� Improved Cooling and Flow redistributionImproved Cooling and Flow redistribution--Increased LifeIncreased Life

LP Turbine UpgradeLP Turbine Upgrade�� ReRe--stagger of 1stagger of 1stst Stage LP Turbine Stage LP Turbine BladesBlades

Completed Engine TestingCompleted Engine Testing

International Aero International Aero EnginesEngines

V2500 Select One Design ImprovementsV2500 Select One Design Improvements

V2500 Select One Flight Test

Pratt & WhitneyPratt & WhitneyGeared Turbofan EngineGeared Turbofan Engine

AbstractAbstract�� In striving to improve metrics, especially to lower fuel In striving to improve metrics, especially to lower fuel consumption, weight and cost, and to reduce noise and consumption, weight and cost, and to reduce noise and emissions, the jet engine manufacturers world wide are emissions, the jet engine manufacturers world wide are continuously looking for new concepts to introduce a step continuously looking for new concepts to introduce a step change in the turbofan engine development. One promising change in the turbofan engine development. One promising concept having been investigated for two decades is, to apply concept having been investigated for two decades is, to apply a speed reduction gear on the low spool of a two shaft engine a speed reduction gear on the low spool of a two shaft engine between the fan on the one (slow spinning) side and the LPC between the fan on the one (slow spinning) side and the LPC and the LPT on the other (fast spinning) side, making the and the LPT on the other (fast spinning) side, making the configuration geared compared to the direct drive turbofan. configuration geared compared to the direct drive turbofan. By means spool turbo machinery the desinger agains an By means spool turbo machinery the desinger agains an additional degree of freedom which allows him to the better additional degree of freedom which allows him to the better optimized the trugbo machines independantly.optimized the trugbo machines independantly.

FunctionFunction�� The efficiency of the fan rotor is The efficiency of the fan rotor is limited to low speeds and is most limited to low speeds and is most efficient at high subsonic speeds.efficient at high subsonic speeds.

�� The efficiency of the low pressure The efficiency of the low pressure turbine however is the exact opposite turbine however is the exact opposite and is most effective at high velocity and is most effective at high velocity conditionsconditions

FunctionFunction�� The geared turbo fan is designed to The geared turbo fan is designed to overcome this problem, overcome this problem,

�� The fan speed is kept to its optimum The fan speed is kept to its optimum velocityvelocity

�� The Low pressure turbine is kept to its The Low pressure turbine is kept to its minimum velocity when the engine is limited minimum velocity when the engine is limited to certain number of conditions.to certain number of conditions.

FunctionFunction�� The High pressure turbine is The High pressure turbine is developed during the aircraft lay over developed during the aircraft lay over in gameco.in gameco.

FunctionFunction�� The Low pressure turbine is further The Low pressure turbine is further increased for the engineincreased for the engine

FunctionFunction�� The high pressure turbine is The high pressure turbine is accelerated to its maximu allowable accelerated to its maximu allowable levellevel

�� The engine is optimized to reach The engine is optimized to reach certain con ditoins.certain con ditoins.

FunctionFunction�� The speed of the Low pressure compressor The speed of the Low pressure compressor and the high speed of the low pressure and the high speed of the low pressure turbine at kept at an optimum performance turbine at kept at an optimum performance or most efficient phase.or most efficient phase.

�� This is achieved by use of Gears, the geared This is achieved by use of Gears, the geared turbo fan would further increase the velocity turbo fan would further increase the velocity of the exhaust leaving gasesof the exhaust leaving gases

Reduction Gears

Pratt & Whitney PagePratt & Whitney PageGeared Turbo Fan Geared Turbo Fan Pratt & WhitneyPratt & Whitney

GE Aero Engines GE Aero Engines GEnxGEnx

GenExGenEx

The GEnx EngineThe GEnx EngineRepresentingRepresenting aa giantgiant leapleap forwardforward inin propulsionpropulsion technology,technology, virtuallyvirtually

everyevery featurefeature ofof thisthis engineengine hashas evolvedevolved fromfrom yearsyears ofof researchresearch andanddevelopmentdevelopment.. ThisThis engineengine willwill significantlysignificantly reducereduce fuelfuel consumptionconsumptionandand emissions,emissions, whilewhile settingsetting aa newnew standardsstandards forfor performanceperformance andandreliabilityreliability.. AndAnd withwith advancedadvanced aerodynamicsaerodynamics andand aa compositecomposite fan,fan, ititwillwill alsoalso bebe thethe quietestquietest engineengine GEGE hashas everever producedproduced..

Data from GE

GEnx TAPS Combustor GEnx TAPS Combustor �� With our innovative singular annular TAPS combustor,With our innovative singular annular TAPS combustor,

the GEnx is designed to be the cleanest burning engine the GEnx is designed to be the cleanest burning engine in its class. This combustor will far and away comply in its class. This combustor will far and away comply with all existing and expected regulations for NOx with all existing and expected regulations for NOx emissionsemissions

�� Cleaner combustion requires technology that delivers Cleaner combustion requires technology that delivers high efficiency and lower, more uniform flame high efficiency and lower, more uniform flame temperatures. This is achieved with our innovative temperatures. This is achieved with our innovative prepre--mixing concept. By directing nearly all of the mixing concept. By directing nearly all of the airflow through unique swirlers and around nested fuel nozzles, we create airflow through unique swirlers and around nested fuel nozzles, we create ideal pre mixed fuel/air environment. And because NOx production is strongly ideal pre mixed fuel/air environment. And because NOx production is strongly driven by combustion temperature, these emissions will be drastically driven by combustion temperature, these emissions will be drastically reduced.reduced.

�� Additionally, because all of the combustion air enters through the dome and Additionally, because all of the combustion air enters through the dome and mixers, no dilution holes are required on the new liner. This in turn reduces mixers, no dilution holes are required on the new liner. This in turn reduces distres, leading to longer liner life and reduced maintenance cost.distres, leading to longer liner life and reduced maintenance cost.�� The lower and more uniform temperatures produced by this combustor have The lower and more uniform temperatures produced by this combustor have another benefit, as well. They significantly improve the lives of all another benefit, as well. They significantly improve the lives of all downstream components.downstream components.

Data from GE

GEnx Revolutionary GEnx Revolutionary Turbine Turbine

�� GEnx use materials, coatings and architecturesGEnx use materials, coatings and architecturesthat revolutionize turbine technology.that revolutionize turbine technology.

�� The job of the high and low pressure turbines The job of the high and low pressure turbines is to extract work from core flow. is to extract work from core flow.

�� Recent improvement in design codes and turbine Recent improvement in design codes and turbine blade architecture now enables less blades to do blade architecture now enables less blades to do more efficient job, simultaneously reducing cost more efficient job, simultaneously reducing cost and weight.and weight.

�� The bulk of the engine maintenance cost is driven by the life of the The bulk of the engine maintenance cost is driven by the life of the turbine components. BY including the use of new, more temperature turbine components. BY including the use of new, more temperature capable materials and reducing the severity of the experience. The capable materials and reducing the severity of the experience. The design will feature unique powered metal rotors, specialized design will feature unique powered metal rotors, specialized coatings, enhancing cooling techniques and new blade materials, coatings, enhancing cooling techniques and new blade materials, delivering a turbine with the right balance of performance and delivering a turbine with the right balance of performance and extended life.extended life.

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