Lecture design 2ICE.pdf
- 1. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Internal Combustion Engine
- 2. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Cylinder Position Refers to the position of the cylinders in relation to the crankshaft There are five basic cylinder arrangements: Horizontal cylinder Inline V-Engine Opposed Cylinder Engine W-Engine Opposed Piston Engine Radial Engine
- 3. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department A. Horizontal cylinder B. Inline C. V-Engine D. Opposed Cylinder Engine E. W-Engine F. Opposed Piston Engine G. Radial Engine
- 4. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department In - Line • Cylinders are positioned in a straight line one behind the other along the length of the crankshaft • 2-11 cylinder • 4 cylinder is very common
- 5. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department V configuration • Two banks of cylinder at an angle with each other along a single crankshaft • Angle between the banks 15º-120º • 60º-90º is very common • Cylinder 2 to 20
- 6. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Horizontally Opposed • Two banks of cylinder at an angle with each other along a single crankshaft V with 180 • Angle between the banks 15º-120º • Cylinder 2 to 20
- 7. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Fuel Type Engines are classified by the type of fuel used Gasoline engines burn gasoline Diesel engines burn diesel fuel Liquefied petroleum gas (LPG), gasohol (10% alcohol, 90% gasoline), and pure alcohol can also be used to power an engine
- 8. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Air Intake Processing • Normal aspiration – atmospheric pressure • Forced induction (Turbo or Supercharger) • Supercharger: Intake air pressure increased by compressor driven by engine crankshaft • Turbocharge : Intake air pressure increased by compressor driven by engine exhaust gases
- 9. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department
- 10. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department
- 11. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Method of Cooling There are two types of cooling systems: Liquid cooling system surrounds the cylinder with coolant coolant carries combustion heat out of the cylinder head and engine block Air cooling system circulates air over cooling fins on the cylinders air removes heat from the cylinders
- 12. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department FIGURE 3-3 The coolant temperature is controlled by the thermostat which opens and allows coolant to flow to the radiator when the temperature reaches the rating temperature of the thermostat.
- 13. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Camshaft Location There are two basic locations for the engine camshaft: Camshaft located in the block cam-in-block engine Camshaft located in the cylinder head overhead cam (OHC) engine
- 14. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Cam in Block (OHV) Uses push rods to transfer motion to the rocker arms and valves Also called an overhead valve (OHV) engine
- 15. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department
- 16. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department
- 17. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Diagram of OHV Note the adjustment screw on the end of the rocker arm. Not all rocker arms have this adjustment. Check the shop manual for adjustment procedures.
- 18. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Cam in Head OHC engines may use one or two camshafts per cylinder head Single overhead cam (SOHC) engine uses only one camshaft per cylinder head Dual overhead cam (DOHC) engine uses two camshafts per cylinder head one cam operates the intake valves, while the other cam operates the exhaust valves
- 19. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Diagram of OHC Notice that the pushrod and rocker arm have been eliminated in this OHC engine. Less moving parts in the transmission of camshaft motion to open the valve. This not only reduces friction points and weight but also less points for wear and component breakage. NOTE-not all OHC have eliminated the rocker arms. (See next slide)
- 20. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Diagram of OHC with Rockers
- 21. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Diagram of DOHC
- 22. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department FIGURE 3-12 SOHC engines usually require additional components such as a rocker arm to operate all of the valves. DOHC engines often operate the valves directly.
- 23. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department FIGURE 3-13 A dual overhead camshaft (DOHC) V-8 engine with the cam cover removed.
- 24. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department • Four wheel drive • Two wheel drive Front wheel driven Back wheel driven
- 25. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Engine Components and Functions
- 26. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Name that Engine Part 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
- 27. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Name that Engine Part Valve cover Valve spring Valve Connecting rod Engine block Rocker arm Push rod Valve tappet Camshaft Connecting rod Main journal Connecting rod cap Piston pin Oil pan Piston
- 28. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Cylinder Block “Backbone” of the engine. Supports / aligns most other components. Part of basic tractor frame. Contains: Cylinders Coolant passages Oil passages Bearings One-piece, gray cast iron
- 29. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Cylinders • Cylindrical holes in which the pistons reciprocate. • May be: – Enblock – Liners • Wet liners • Dry liners • Cylinder bore – diameter of cylinder
- 30. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Checking Cylinder Condition • During engine overhaul, cylinder is checked for: – Excessive wear (oversize) – Out-of Round – Taper
- 31. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Bearings and Journals Bearing Journal • Bearing – Stationary (non- rotating) surfaces providing support to moving (rotating) component. – Main bearings – Rod bearings – Cam bearings • Journal – Surface of moving component supported by a bearing.
- 32. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Cylinder Head Seals the “top-end” of the combustion chamber. Contains the valves and the intake and exhaust “ports”. Head bolts and head gasket ensure air- tight seal of the combustion chamber. Contains oil and coolant passages. One-piece castings of iron alloy.
- 33. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Valve Train • Controls flow into and out of the combustion chamber. – Time and Duration • Tractor engines use “Overhead Valve (OHV)” configuration. • Components – Camshaft – Valve tappets – Push rods – Rocker arm – Valves – Valve springs – Valve rotators – Valve seats
- 34. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Camshaft Lift Base circle Nose Cam Profile Open the intake and exhaust valves at correct time and for correct duration. Driven by gear (or chain) from the crankshaft. 2:1 crankshaft to camshaft gear ratio.
- 35. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Piston and Rings • Piston – Forms the “moveable bottom’ of the combustion chamber. • Iron alloy or aluminum • Rings – Compression – Oil-control • Cast iron • Piston pin
- 36. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department
- 37. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Know Your Piston!
- 38. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department
- 39. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department
- 40. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Connecting rod • Connects the piston to the crankshaft • Converts reciprocating piston motion to rotary motion at the crankshaft. • Nomenclature • Drop-forged steel
- 41. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Flywheel: Rotating mass with a large moment of inertia connected to the crankshaft of the engine. The purpose of the flywheel is to store energy and furnish a large angular momentum that keeps the engine rotating between power strokes and smooths out engine operation
- 42. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Fuel injector :A pressurized nozzle that sprays fuel into the incoming air on SI engines or into the cylinder on CI engines. On SI engines, fuel injectors are located at the intake valve ports on multipoint port injector systems and upstream at the intake manifold inlet on throttle body injector systems. In a few SI engines, injectors spray directly into the combustion chamber
- 43. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Push rod: Mechanical linkage between the camshaft and valves on overhead valve engines with the camshaft in the crankcase. Many push rods have oil passages through their length as part of a pressurized lubrication system
- 44. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department
- 45. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department
- 46. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Crankshaft Works with connecting rod to change reciprocating to rotary motion. Transmits mechanical energy from the engine. Made of heat-treated steel alloys.
- 47. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Cylinder Bore Bore is the diameter of the cylinder
- 48. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department FIGURE 3-6 Cutaway of an engine showing the cylinder, piston, connecting rod, and crankshaft.
- 49. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Valves • Each cylinder will have: – Intake valve – Exhaust valve • Valve nomenclature – Head – Margin – Face – Tulip – Stem
- 50. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department
- 51. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Water jacket: System of liquid flow passages surrounding the cylinders, usually constructed as part of the engine block and head. Engine coolant flows through the water jacket and keeps the cylinder walls from overheating. The coolant is usually a water-ethylene glycol mixture.
- 52. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department Carburetor : Venturi flow device which meters the proper amount of fuel into the air flow by means of a pressure differential
- 53. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department
- 54. Sana’a University Dr. Abduljalil Al-Abidi Internal combustion engine Mechanical Engineering department FIGURE 3-4 A typical lubrication system, showing the oil pan, oil pump, oil filter, and oil passages. Oil pump