TM 55-2840-241-23
298995
Figure 1-2. Engine Airflow
1-6. Compressor.
a. The compressor assembly consists of a com-
pressor front support, case assembly with stator vanes,
rotor assembly with blades, centrifugal impeller, front
diffuser assembly, rear diffuser assembly, and diffuser
scroll. Air enters the compressor through the front
support. (See figure 1-2.) Struts in the support guide
the air and direct it in the proper direction into the first
stage of the compressor rotor. The air is then com-
pressed by six axial compressor stages and one cen-
trifugal stage. As the air passes through the axial
stages, it is alternately accelerated by the rotor blades
and decelerated by the stator vanes. At the same time,
it is compressed into an ever decreasing space. This
results in an increase in both air pressure and tem-
perature.
b. The sixth-stage compressor vanes direct the com-
pressor air into the impeller. The impeller vanes cen-
trifugally accelerate the air through an ever
decreasing space to further increase the air pressure
and temperature. It is then discharged across the dif-
fuser vanes and directed into the diffuser scroll.
c. The diffuser scroll collect the compressor dis-
charge flow at a constant velocity and directs it rear-
ward through two ports (one on each side of the engine)
to the combustion section. Each of the ports has turn-
ing vanes which direct the air rearward.
1-7. Combustion Section.
a. The combustion section consists of two com-
pressor discharge air tubes (one on each side of the
Change 14 1-3
