Caterpillar TAURUS 70 - Manual (Page 11)

Turbomachinery Package Specification Taurus 70 Compressor Set and Mechanical Drive
3 Taurus 70 Gas Turbine
3.1 General Description
The two-shaft Taurus 70 gas turbine (Figure 3) is a completely integrated and self-
contained prime mover. The gas turbine combines high performance operation with
rugged industrial construction. This design philosophy allows for high efficiency, low
maintenance, and a long service life. The Taurus 70 gas turbine is designed for a high
degree of compliance with American Petroleum Institute (API) requirements.
Figure 3. Typical Taurus 70 Two-Shaft Gas Turbine
3.1.1 Principles of Operation
During the typical combustion process (Figure 4), air is drawn into the gas turbine air inlet
and is compressed by the multi-stage, axial-flow engine compressor. The compressed air
is directed into the annular combustion chamber at a steady flow. Fuel is injected and
mixed with the compressed air and ignited during the start cycle. Continuous combustion
will be maintained as long as there is an adequate flow of pressurized air and fuel. Hot-
pressurized gas from the combustor expands through and drives the turbine, dropping in
pressure and temperature as it exits the turbine. This combustion cycle converts the
energy in the fuel into kinetic rotating power at the turbine output shaft.
For combustion, the gas turbine requires approximately one-fourth of the total air it
compresses. The excess air is mixed with the combustion products to reduce the gas
temperature at the turbine first stage-inlet. The cooling air also keeps metal temperatures
in the combustor and turbine assembly relatively low to ensure a long service life.
© 2009 Solar Turbines Incorporated. All rights reserved. TPS70CSMD/309
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