A portion of the kinetic energy of the expanding gases is
extracted by the turbine section, and this energy is transformed into
accessories. In turboprop and turboshaft engines, additional turbine
rotors are designed to extract all of the energy possible from the
remaining gases to drive a powershaft.
a. Types of turbines. Gas turbine manufacturers have
concentrated on the axialflow turbine shown in figure 1.21. This
turbine is used in all gasturbinepowered aircraft in the Army
today. However, some manufacturers are building engines with a
radial inflow turbine, illustrated in figure 1.22. The radial inflow
Figure 1.21. Axialflow Turbine Rotor.
has the advantage of ruggedness
and simplicity, and it is
relatively inexpensive and easy
to manufacture when compared to
the axialflow turbine. The
radial flow turbine is similar in
design and construction to the
described in paragraph 1.19a.
Radial turbine wheels used for
Figure 1.22. Radial Inflow