Mechanical Engineering - IC Engines and Nuclear Power Plants - Discussion

Longer ignition delay is preferred in a spark ignition engine to prevent pre ignition.

In case of diesel a shorter ignition delay is preferred to prevent detonation or a sudden pressure rise.

Detonation is more dangerous and may damage the piston compared to pre ignition.

If ignition delay is more than it takes more time to generate flame and for travelling of flame & during that due to compression temperature of fuel particles may increase more than it's self-ignition temperature and it favours knocking.

Please, anyone tell me that it is right or not?

I want a detailed explanation about this question. Will you please give it?

@ALL

As per;
1) spark ignition engine.
2) octane number.

Spark ignition engine refers to petrol engines in which the fuel/air mix gets ignited by the spark produced by the spark plug.

Octane rating is used as a measure to evaluate the quality of fuel used in the petrol engines.

Higher the octane rating, more the fuel is capable of withstanding higher temperature and pressure.

Longer ignition delay is preferred in a spark ignition engine to prevent pre-ignition.