8 Questions
What is detonation?
Part of the air/fuel mixture exploding outside the normal combustion front
What is the effect of detonation on cylinder pressure?
Increases cylinder pressure dramatically
How can detonation be prevented in an engine?
By controlling peak combustion chamber temperatures, compression ratio reduction, exhaust gas recirculation, ignition timing schedule, and careful design of the engine's combustion chambers and cooling system
Which element added to certain fuels can suppress detonation?
Lead
What is the effect of water injection on knock in engines?
Reduces knock
Which type of paraffins resist knock?
Branched chain paraffins
What is the effect of turbulence on knock in engines?
Reduces knock
What causes a different kind of knock in diesel engines?
Fast rate of pressure rise
Study Notes
- Detonation occurs when part of the air/fuel mixture explodes outside the normal combustion front
- This creates a metallic "pinging" sound and increases cylinder pressure dramatically
- Effects range from inconsequential to destructive, damaging engine components
- Detonation can be prevented by controlling peak combustion chamber temperatures, compression ratio reduction, exhaust gas recirculation, ignition timing schedule, and careful design of the engine's combustion chambers and cooling system
- Lead and thallium added to certain fuels can suppress detonation
- Knock is less common in cold climates and water injection system can be used to reduce peak temperatures
- Branched chain paraffins resist knock while straight chain paraffins knock easily
- Turbulence has a significant effect on knock, engines with good turbulence tend to knock less
- Diesel engines suffer from a different kind of knock caused by a fast rate of pressure rise
- Careful design of injector pump, fuel injector, combustion chamber, piston crown, and cylinder head can reduce knocking in diesel engines
Think you know everything about engine knock and detonation? Test your knowledge with this quiz! Learn about the causes and effects of engine knock, and discover the various methods to prevent it from happening. From controlling peak temperatures to fuel additives, this quiz covers all the ways to keep your engine running smoothly. Whether you're a car enthusiast or a mechanic, this quiz is sure to challenge your understanding of engine knock and detonation.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
