886
CHAPTER 27
INTERNAL COMBUSTION ENGINES
Ronald Douglas Matthews
Department of Mechanical Engineering
The University of Texas at Austin
Austin, Texas
1 TYPES AND PRINCIPLES OF
OPERATION
886
1.1 Spark Ignition Engines
888
1.2 Compression Ignition
(Diesel) Engines
894
2 FUELS AND KNOCK
895
2.1 Knock in Spark Ignition
Engines
895
2.2 Knock in the Diesel Engine
897
2.3 Characteristics of Fuels
897
3 PERFORMANCE AND
EFFICIENCY
901
3.1 Experimental Measurements
902
3.2 Theoretical Considerations
and Modeling
904
3.3 Engine Comparisons
909
4 EMISSIONS AND FUEL
ECONOMY REGULATIONS
912
4.1 Light-Duty Vehicles
912
4.2 Heavy-Duty Vehicles
916
4.3 Nonhighway Heavy-Duty
Standards
917
SYMBOLS
917
REFERENCES
919
BIBLIOGRAPHY
921
An internal combustion engine is a device that operates on an open thermodynamic cycle
and is used to convert the chemical energy of a fuel to rotational mechanical energy. This
rotational mechanical energy is most often used directly to provide motive power through
an appropriate drive train, such as for an automotive application. The rotational mechanical
energy may also be used directly to drive a propeller for marine or aircraft applications.
Alternatively, the internal combustion engine may be coupled to a generator to provide
electric power or may be coupled to hydraulic pump or a gas compressor. It may be noted
that the favorable power-to-weight ratio of the internal combustion engine makes it ideally
suited to mobile applications and therefore most internal combustion engines are manufac-
tured for the motor vehicle, rail, marine, and aircraft industries. The high power-to-weight
ratio of the internal combustion engine is also responsible for its use in other applications
where a lightweight power source is needed, such as for chain saws and lawn mowers.
This chapter is devoted to discussion of the internal combustion engine, including types,
principles of operation, fuels, theory, performance, efficiency, and emissions.
1 TYPES AND PRINCIPLES OF OPERATION
This chapter discusses internal combu