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1. E 2. Suction
Main rotor flutes
‘a’, ‘b’ and ‘c’ are in
communication at one end with the suction
chamber and are sealed at the other end by
the upper satellite teeth. As the main rotor
turns, the effective length of the flutes
increases, thus increasing the volume open to
the suction chamber. Figure 1 clearly
illustrates this process. As flute
‘a’ assumes
the position of flutes
‘b’ and ‘c’ its volume
increases, inducing suction vapour to enter the
flute.
Upon further rotation of the main rotor, the
flutes which have been open to the suction is
chamber engage with the satellite teeth. This
coincides with each flute being progressively
sealed by the main rotor.
Once the flute volume is closed off from the
suction chamber, the suction stage of the
compression cycle is complete.
1.
2.
3. Compression
As the main rotor turns, the volume of gas
trapped within the flute is reduced as the
length of the flute shortens and compression
occurs.
3.
4. Discharge
As the satellite tooth approaches the end of a
flute, the pressure of the trapped vapour
reaches a maximum value occurring when the
leading edge of the flute begins to overlap the
triangular
shaped
discharge
port.
Compression immediately ceases as the gas
is delivered into the discharge manifold. The
satellite tooth continues to scavenge the flute
until the flute volume is reduced to zero. This
compression process is repeated for each
flute/satellite tooth in turn.
4.
Oil separator not shown
Fig. 25 - Compression process
c
b
a
c
a
b
c
b
a
a
b
Discharge
gas
a
b
Su
ct
io
n
G
a
s
b
a
c
