1 / 25

Internal Combustion Engines – The Diesel

Internal Combustion Engines – The Diesel. Objectives. Uses for internal combustion engines Thermodynamic principles involved Components and purposes of each Operation of systems Two stroke engines Four stroke engines. The Diesel is a Hacker. Engine Uses. Emergency Diesel Generators (EDG)

indira-cunningham
Download Presentation

Internal Combustion Engines – The Diesel

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Internal Combustion Engines –The Diesel

  2. Objectives • Uses for internal combustion engines • Thermodynamic principles involved • Components and purposes of each • Operation of systems • Two stroke engines • Four stroke engines

  3. The Diesel is a Hacker

  4. Engine Uses • Emergency Diesel Generators (EDG) • Propulsion • Certain amphibious landing ships • Mine warfare ships • Patrol craft • Tug boats • Small boats • Outboard motors

  5. Thermodynamic Principles • All internal combustion • Open cycle, heated engine • Gasoline (Otto) engine • Spark ignition • Compresses air-fuel mixture • Diesel engine • Compressed ignition • Compresses air only

  6. Structural Components • Cylinder Block • Part of engine frame that contains cylinders in which piston moves • Supports liners & head

  7. Structural Components • Cylinder Head/Assembly • Serves to admit, confine, and release fuel/air • Cover to cylinder block • Supports valve train • Crankcase • Engine frame section that houses the crankshaft • Oil sump • Reservoir for collecting and holding lube oil

  8. Moving Components • Three Groups – according to motion • Reciprocating only (pistons and valves) • Reciprocation & rotary (connecting rods) • Rotary only (crankshafts and camshafts)

  9. Moving Components • Piston • Acted on by combustion gases • Lightweight but strong/durable • Piston Rings • Transfer heat from piston to cylinder • Seal cylinder & distribute lube oil • Piston Pin • Pivot point connecting piston to connecting rod • Connecting Rod • Connects piston & crankshaft • reciprocating rotating motion

  10. Moving Components • Crankshaft • Combines work done by each piston • Drives camshafts, generator, pumps, etc. • Flywheel • Absorbs and releases kinetic energy of piston strokes -> smoothes rotation of crankshaft

  11. Moving Components • Valves • Intake: open to admit air to cylinder (with fuel in Otto cycle) • Exhaust: open to allow gases to be rejected • Camshaft & Cams • Used to time the addition of intake and exhaust valves • Operates valves via pushrods & rocker arms

  12. Operation • Increased pressure of combustion gases acts on piston -> converted to rotary motion • Can be 2 or 4 stroke engines • 2-stroke: 1 power stroke per 1 crankshaft rev • 4-stroke: 1 power stroke per 2 crankshaft rev

  13. Operation • Engine stroke • A stroke is a single traverse of the cylinder by the piston (from TDC to BDC) • 1 revolution of crankshaft = 2 strokes of piston

  14. Four-Stroke Diesel Engine • Intake stroke • Intake valve open, exhaust valve shut • Piston travels from TDC to BDC • Air drawn in • Compression stroke • Intake and exhaust valves shut • Piston travels from BDC to TDC • Temperature and pressure of air increase

  15. Four-Stroke Diesel Engine • Power stroke • Intake and exhaust valves shut • Fuel injected into cylinder and ignites • Piston forced from TDC to BDC • Exhaust stroke • Intake valve shut, exhaust valve open • Piston moves from BDC to TDC • Combustion gases expelled

  16. Four-Stroke Diesel Engine • Strokes • Intake • Compression • Power • Exhaust

  17. Two-Stroke Diesel Engine • 1 power stroke every crankshaft revolution (vice every two w/ 4-stroke) • Uses pressurized air to simultaneously supply new air and expel combustion gases • Scavenging • Exhaust valve open, inlet port exposed • Pressurized air enters, expels combustion gases • Piston near BDC

  18. Two-Stroke Diesel Engine • Compression • Intake and exhaust valves shut • Piston travels from BDC to TDC • Temperature and pressure of air increase • Power stroke • Intake and exhaust valves shut • Fuel injected into cylinder and ignites • Piston forced from TDC to BDC

  19. Two-Stroke Diesel Engine • Strokes • Compression • Power • (Intake/Exhaust)

  20. Two vs. Four-Stroke Engines • Two-stroke advantages • Higher power to weight ratio • Less complicated valve train • Four-stroke advantages • More efficient burning process • As size increases, power-to-weight ratio improves

  21. Gasoline vs. Diesel Engine

  22. Supporting Systems • Air system • Supplies & removes air/gases • Air supplied at constant pressure by blower/compressor • Fuel System • Carburetor: mixes air & fuel in proper proportion (NOT on diesels) • Fuel injector: sprays fuel in (more efficient)

  23. Supporting Systems • Ignition system • Diesel has compression ignition • Gasoline has spark plugs • Cooling system • Uses fresh water and/or salt water to cool • Lubrication system • Provide lubrication and cooling • Drive Train – Direct or Indirect

  24. Safety Precautions • Noise • Fuel Flammability • Maintenance • Water Issues

  25. Questions?

More Related