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1-MS-Module 1-Diesel Engine Fundamentals DOE Fundamentals MECHANICAL SCIENCE Module 1 Diesel Engine Fundamentals Mechanical Science Diesel Engine Fundamentals TABLE OF CONTENTS TABLE OF CONTENTS .............................................................................................................. ii LIST OF FIGURES .................................................................................................................... iv LIST OF TABLES ....................................................................................................................... vi REFERENCES ......................................................................................................................... vii OBJECTIVES .......................................................................................................................... viii DIESEL ENGINES ..................................................................................................................... 1 Introduction ............................................................................................................................ 1 History .................................................................................................................................... 2 Diesel Engines ....................................................................................................................... 2 Major Components of a Diesel Engine.................................................................................... 3 The Cylinder Block ................................................................................................................. 5 Crankcase and Oil Pan ........................................................................................................... 6 Cylinder Sleeve or Bore .......................................................................................................... 6 Piston and Piston Rings ......................................................................................................... 7 Connecting Rod ...................................................................................................................... 7 Crankshaft .............................................................................................................................. 7 Flywheel ................................................................................................................................. 8 Cylinder Heads and Valves .................................................................................................... 9 Timing Gears, Camshaft, and Valve Mechanism ................................................................... 9 Blower ...................................................................................................................................11 Diesel Engine Support Systems ............................................................................................11 Exhaust System ....................................................................................................................15 Operational Terminology .......................................................................................................15 Bore and Stroke ....................................................................................................................15 Summary ..................................................................................................................................17 FUNDAMENTALS OF THE DIESEL CYCLE ............................................................................18 The Basic Diesel Cycles ........................................................................................................18 The Four-Stoke Cycle ............................................................................................................19 The Two-Stroke Cycle ...........................................................................................................22 Summary ..................................................................................................................................24 MS-01-ii Mechanical Science Diesel Engine Fundamentals DIESEL ENGINE SPEED, FUEL CONTROLS, AND PROTECTION ........................................26 Engine Control .......................................................................................................................26 Fuel Injectors .........................................................................................................................26 Governor ...............................................................................................................................29 Operation of a Governor ........................................................................................................30 Starting Circuits .....................................................................................................................32 Engine Protection ..................................................................................................................33 Summary ..................................................................................................................................35 MS-01-iii Mechanical Science Diesel Engine Fundamentals LIST OF FIGURES Figure 1 Example of a Large Skid-Mounted, Diesel-Driven Generator ...................................... 2 Figure 2 Cutaway of a Four-Stroke Supercharged Diesel Engine .............................................. 4 Figure 3 Cross Section of a V-type Four Stroke Diesel Engine ................................................. 5 Figure 4 The Cylinder Block ....................................................................................................... 5 Figure 5 Diesel Engine Wet Cylinder Sleeve ............................................................................. 6 Figure 6 Piston and Piston Rod ................................................................................................. 7 Figure 7 Diesel Engine Crankshaft and Bearings ...................................................................... 8 Figure 8 Diesel Engine Valve .................................................................................................... 9 Figure 9 Diesel Engine Camshaft and Drive Gear ..................................................................... 9 Figure 10 Diesel Engine Valve Train ....................................................................................... 10 Figure 11 Diesel Engine Cooling System ................................................................................ 11 Figure 12 Diesel Engine Internal Lubrication System .............................................................. 12 Figure 13 Diesel Engine Fuel Flowpath ................................................................................... 13 Figure 14 Oil Bath Air Filter ..................................................................................................... 14 Figure 15 Compression Ratio .................................................................................................. 16 Figure 16 Scavenging and Intake ............................................................................................ 19 Figure 17 Compression ........................................................................................................... 20 Figure 18 Fuel Injection ........................................................................................................... 20 Figure 19 Power ....................................................................................................................... 21 Figure 20 Exhaust ................................................................................................................... 21 Figure 21 2-Stroke Exhaust ..................................................................................................... 22 Figure 22 2-Stroke Intake ........................................................................................................ 22 Figure 23 2-Stroke Compression ............................................................................................. 23 Figure 24 2-Stroke Fuel Injection ............................................................................................ 23 Figure 25 2-Stroke Power ....................................................................................................... 23 MS-01-iv Mechanical Science Diesel Engine Fundamentals Figure 26 Fuel Injector Cutaway ............................................................................................. 27 Figure 27 Fuel Injector Plunger ............................................................................................... 28 Figure 28 Simplified Mechanical-Hydraulic Governor .............................................................. 30 Figure 29 Cutaway of a Woodward Governor .......................................................................... 31 MS-01-v Mechanical Science Diesel Engine Fundamentals LIST OF TABLES NONE MS-01-vi Mechanical Science Diesel Engine Fundamentals REFERENCES Benson & Whitehouse, Internal Combustion Engines, Pergamon. Cheremisinoff, N. P., Fluid Flow, Pumps, Pipes and Channels, Ann Arbor Science. Scheel, Gas and Air Compression Machinery, McGraw/Hill. Skrotzki and Vopat, Steam and Gas Turbines, McGraw/Hill. Stinson, Karl W., Diesel Engineering Handbook, Diesel Publications Incorporated. MS-01-vii Mechanical Science Diesel Engine Fundamentals OBJECTIVES TERMINAL
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