Gas Turbine Handbook : Principles and Practices

Preface to the Third Edition
The need for the 2 nd Edition was based on the realization that
the book lacked sufficient guidelines in projects that I was involved with;
specifically, wet compression and acoustics. In 2002 I updated this book
with the 2 nd Edition.
This 3 rd Edition is undertaken to cover a subject that captured my
time and attention and is of interest to many people not usually involved
with gas turbines. This subject is microturbines. Microturbines were first
considered a viable product in the early-to-mid 1990’s. Part of the popularity
with the idea of a very small gas turbine was the result of the successes
with miniaturization in the electronic industry; part was the lack of
competition for reciprocating engines; and part was the steadily increasing
price & decreasing availability of electricity. Price and availability of
electricity led to the concept now known as Distributed Generation (DG).
And the microturbine fits DG to a tee.
Looking back into 19 th Century history, machines strikingly similar
to today’s microturbine were being developed. True they were large,
bulky machines, but they had the same characteristics. For example, they
had centrifugal compressors & turbines, single combustors and, in some
cases, a heat exchanger that captured exhaust gases to heat the compressor
discharge air before it entered the combustor (a recuperator or regenerator).
Each was a stand-alone component coupled together by shafts, hubs,
and ducting. But thermodynamically these machines are identical.
Prior to the introduction of microturbines the only drivers available
in the 600 and under horsepower range were reciprocating engines.
These reciprocating engines are large, they vibrate, they are noisy, they
are fuel specific, and they require frequent maintenance. By comparison
the microturbine is small, quiet, relatively vibration and maintenance free,
and tolerant of a wide range of fuels.
The microturbine innovators had the vision to see the potential
in a very small gas turbine. A vision similar to Frank Whittle’s and Hans
Pabst von Ohain’s vision of utilizing a gas turbine for jet power. They
were able to look at engine turbocharger components and visualize how
the addition of a combustor could turn them into a gas turbine. Further,
they could visualize how a recuperator, wrapped around the combustor
could enhance performance, reduce emissions, and minimize the package
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