Engineering · Diesel — Fuel
The cetane number of a diesel fuel is a measure of its:
- AResistance to knock in a spark engine
- BIgnition quality — how readily it ignites under compression✓ Correct
- CSulfur content
- DViscosity at 40 degrees C
Explanation
Cetane number rates ignition quality: a higher number means a shorter ignition delay and smoother combustion. (Octane, by contrast, rates knock resistance in gasoline engines.)
Authority: Diesel Fuels (USCG engineering topic)
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