1.5 Flashcards
Front Frame Location
Front of compressor section
Front Frame Description
Welded steel ring that houses inlet guide vanes
Inlet Guide vanes
hollow to allow for hot air from engine to circulate through the vanes to prevent ice from forming
also provides lubrications oil to and from main bearing
Air Inlet Duct
Preswirls front frame in direction of rotation of engine compressor rotor to prevent shock
Compressor section Location
Between front frame and combustion section
Compressor consist of
Casing, rotor assembly, stator assembly, exit guide vane assembly, and diffuser
Compressor Section main purpose
supplies air in sufficient quanitities to satisfy the requirements of the combustion section
Compressor section purpose,cont.
Heating/as cabin pressurization cooling of engine cavities pressurization of fuel cells and transfer of fuelk anti-icing oil seal pressurization
Compressor section os of the axial flow type
Compressor section os of the axial flow type
axial flow compressor
compresses air in direction that is parallel to axis of engine
axial flow compressor consists
alternating series of rotating airfoils(blads) and stationary airfoils(stator vanes)
axial flow compressor casing
houses the stator assemblies
provides mountaing pads for accessories and bleed air ports.
axial flow compressor rotor assembly consist of
Shaft, disks, blades
blades are attached to compressor disk by dove tail, bulb, or fir tree root. locked in place by peening pins locking wires or keys
axial flow compressor rotor assembly blades are made of
stainless steel, aluminum, or titanium
axial flow compressor stator assembly consist of
stationary vanes dove-tailed into split0rings and mounted to compressor casing.
axial flow compressor stator assembly banes are made from
aluminum titatnium or staineless steel
exit guide vanes location
at compressor exit
exit guide vanes are
stationary vanes that straighten air to eliminate turbulence
diffuser located
part of compressor section
diffuser forms
the compressor rear frame
diffuser develops
a pressure wall to prevent reverse flow of combustion gases back into compressor
high pressure point
diffuser
types of axial flow compressor
single and dual
advantage of axial flow compressor(compared to centrifugal cflow compressor)
high peak efficiencies
small frontal area
disadvantage of axial flow compressor
heavy
difficult to manufacturer
high starting power requirements
Combustion section location
between compressor and turbine
Combustion section purpose
to burn the fuel/air mixture, adding heat energy to mass airflow
combustion section components
Casing chambers ignitor plugs fuel nozzles fuel drain
Type of fuel nozzles
Duplex and simplex
fuel drain
located at bottom of combustion casing. drains residual fuel
Type of combustion chambers
Annular and can-annular
Annular
limited area,1 chamber
can-annular
mulitble chambers
Turbine section locationg
between combustion and exhaust
Turbine purpose
extract energy from expanding gases from combustion section and xonvert gases to shaft horsepower
turbine energy determined by
compressor size, number of engine driven accessories, reduction gearboxes to drive propellars, rotary airfois driven by shafts
Trubine section components
Casing
Nozzles assemblies
turbine rotar assembly
Types of turbine blades
impulse - light
reaction - medium
impulse reaction - heavy
Exhaust section location
Aft of turbine section
Exhaust section purpose
collect exhaust gases and deliver them to exhaust nozzles
mounting for thermocouplings’
provide mounting for struts
Exhaust section inner cone
prevents turbulence and allows gases to come together to form a solid jet stream
Tailpipe
used to carry exhaust gases away from airframe(apart of aircraft not engine)
exhaust nozzles purpose
impart final boost in velocity to gases leaving engine(provide thrust)
thermocouples location
forward, aft or between turbine stages
thermocouples purpose
monitor termp throughout system
Insulation blankets
protect airframe from heat
Power Take Off location
center front of compressor hub
Power take off purpose
change compressor rotor speeds suitable drive speeds
