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Related to cetane number: diesel index
A performance rating for diesel fuels, with a higher number indicating greater fuel efficiency. The number corresponds to the percentage of cetane in a cetane-heptamethylnonane mixture, or (and originally) in a cetane-methylnaphthalene mixture, with the same ignition performance as the fuel being rated. Also called cetane rating.
(Chemistry) a measure of the quality of a diesel fuel expressed as the percentage of cetane in a mixture of cetane and 1-methylnapthalene of the same quality as the given fuel. Also called: cetane rating Compare octane number
a measure of the ignition quality of diesel fuel.