Page 14 - Piston Engine-Based Power Plants

An Introduction to Piston Engine Power Plants 7

Other internal combustion engine cycles were also being pursued.
Two men, German engineer, Karl Benz and an Englishman, Dugald
Clark, independently developed two stroke engines in 1878. Benz
received a patent for his design in Germany in 1879 while Clark
obtained a patent in England in 1881. Benz went on to develop and
patent spark plugs, the carburettor and the clutch and gear shift.

The other main branch of internal combustion reciprocating engines
was also launched by a German engineer, Rudolf Diesel. He had stud-
ied thermodynamics closely and was seeking a more efficient engine.
This led him to the design of the compression ignition engine in 1892
and a patent for the design in 1893. The principle difference between
this and Otto’s engine was that instead of an air fuel mixture being
admitted into the cylinder before compression, only air was admitted
and it was compressed more highly than in the Otto engine. This ele-
vated the temperature of the air to a point at which fuel, when admit-
ted, ignited spontaneously. The diesel engine has become widely used
in many applications because of its greater fuel efficiency. However the
engine produces more polluting emissions than the Otto cycle engine
and widespread use is being questioned today, particularly for road
vehicles.
Since the pioneering work of the late 19th century there have been
major refinements to both Otto cycle and Diesel engine design. These
include turbo charging or supercharging, the introduction of advanced
electronic ignition systems and a range of different engine configura-
tions. There have also been attempts at different designs. During the
early years of the 20th a rotary engine, in which a circular arrangement
of cylinders rotated around a stationary crankshaft became popular,
particularly for aircraft. However inherent limitations led designers
back to the traditional reciprocating design as this advanced. A
completely different rotary engine, the Wankel engine, was developed
later in the century but has also found only limited application.

GLOBAL RECIPROCATING ENGINE, POWER GENERATION
INSTALLATIONS

The application of reciprocating engines for power generation is so
large and diverse that it is impossible to gauge accurately the total
installed capacity of this type of generator, either by country or