Motores de combustão interna

Engineering Fundamentals of the
Internal Combustion Engine

. i Willard W. Pulkrabek
University of Wisconsin-· .. Platteville

vi

Contents

2-3
2-4
2-5
2-6
2-7
2-8
2-9
2-10
2-11
2-12

3

ENGINE CYCLES

3-1
3-2
3-3
3-4
3-5
3-6
3-7
3-8
3-9
3-10
3-11
3-12
3-13
3-14

4

Mean Effective Pressure, 49
Torque and Power, 50
Dynamometers, 53
Air-Fuel Ratio and Fuel-Air Ratio, 55
Specific Fuel Consumption, 56
Engine Efficiencies, 59
Volumetric Efficiency, 60
Emissions, 62
Noise Abatement, 62
Conclusions-Working
Equations, 63
Problems, 65
Design Problems, 67

68

Air-Standard Cycles, 68
Otto Cycle, 72
Real Air-Fuel Engine Cycles, 81
SI Engine Cycle at Part Throttle, 83
Exhaust Process, 86
Diesel Cycle, 91
Dual Cycle, 94
Comparison of Otto, Diesel, and Dual Cycles, 97
Miller Cycle, 103
Comparison of Miller Cycle and Otto Cycle, 108
Two-Stroke Cycles, 109
Stirling Cycle, 111
Lenoir Cycle, 113
Summary, 115
Problems, 116
Design Problems, 120

THERMOCHEMISTRY

4-1
4-2
4-3
4-4
4-5
4-6
4-7

,

AND FUELS

Thermochemistry, 121
Hydrocarbon Fuels-Gasoline, 131
Some Common Hydrocarbon Components, 134
Self-Ignition and Octane Number, 139
Diesel Fuel, 148
Alternate Fuels, 150
Conclusions, 162
Problems, 162
Design Problems, 165

121

Contents vii 5

AIR AND FUEL INDUCTION
166
5-1
5-2
5-3
5-4
5-5
5-6
5-7

Intake Manifold, 166
Volumetric Efficiency of SI Engines, 168
Intake Valves, 173
Fuel Injectors, 178
Carburetors, 181
Supercharging and Turbocharging, 190
Stratified Charge Engines and Dual Fuel Engines, 195
5-8 Intake for Two-Stroke Cycle Engines, 196
5-9 Intake for CI Engines, 199
5-10 Conclusions, 201
Problems, 202
Design Problems, 204
6

FLUID MOTION WITHIN COMBUSTION
6-1
6-2
6-3
6-4
6-5
6-6
6-7
6-8

7

CHAMBER

206

Turbulence, 206
Swirl, 208
Squish and Tumble, 213
Divided Combustion Chambers, 214
Crevice Flow and Blowby, 215