area between the compressor rotor sleeve and the rotor disk inside
diameters, then forward to the first stage rotor disk where it is
bled back into the compressor airstream through holes in the first
stage spacer. This airflow cools the three aluminum disks in the
compressor rotor assembly. Compressed air bled from the tip of the
centrifugal compressor impeller (2) cools the forward face of the
diffuser housing and pressurizes the No. 2 bearing forward seal, and
continues rearward through transfer tubes in the bearing housing to
pressurize the No. 2 aft oil seal. It also passes through a series
of holes in the rear compressor shaft into the space between the
rotor assembly and the power shaft. At this point, it separates into
three flow paths. Part of the compressed air, used for seal
pressurization, flows forward and through a series of holes in the
compressor front shaft. This air fills the area between the carbon
elements of the No. 1 bearing seal. The intershaft seal, located
forward of the No. 1 bearing, prevents flow of pressurized air into
the inner inlet housing area. A portion of this compressed air flows
aft over the power shaft and emerges at the aft end of the rear
compressor shaft to cool the rear face of the second gas producer
(GP) rotor, the forward face of the first power turbine (PT) rotor,
and the first stage PT nozzle. The air then passes into the exhaust
stream. The remainder of the compressed air flows through a series
of holes in the power shaft. This air flows aft, inside the power
shaft, through holes drilled in the hollow powershaft through bolt,
and into the interior of the second PT rotor assembly. Air then
passes through a series of holes in the turbine hub and the turbine
spaces to cool the rear surface of the first PT rotor assembly, the
forward surface of the second PT rotor assembly, and both faces of
the second PT nozzle.
Compressed air, bled through slots in the mating surfaces of
the combustion chamber deflector and the air diffuser (3) cools the
forward face of the deflector and the No. 2 bearing housing. Then
the air is split into paths to cool the blade roots of the first
stage GP rotor assembly. The air then flows through holes in the
inside diameter of the GP turbine spacer to cool the hub area of the
rear face of the first GP turbine and the forward face of the second
GP turbine. The air then flows rearward where it joins the cooling
air being discharged from the aft end of the compressor shaft where
it is expelled into the exhaust stream.
Compressed air is then directed through the first stage GP
nozzle and cylinder assembly (4) to cool the rear face of the first
stage GP rotor and then into the exhaust stream.
Ambient air is used to cool the No. 3 and No. 4 bearing
housing. The air enters the exhaust diffuser struts (5) and moves
forward
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