Diesel hexadecane
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I’m confused – what is the relationship between diesel density and cetane number? What is the relationship between the initial boiling point and cetane number? What is the relationship between the boiling range and cetane number? I would appreciate some guidance from experts.
Cetane number is an indicator used to measure the combustion performance of diesel. A high cetane number indicates good ignition properties of the fuel, a short afterflame period, and uniform and complete combustion. It is specified that the cetane number of n-hexadecane is 100, and that of heptamethylnonane is 15. The cetane number of diesel depends on its chemical composition, and the cetane numbers of various hydrocarbons follow this order from highest to lowest: alkanes > alkenes > cycloalkanes > aromatic hydrocarbons. Normal alkanes have a high cetane number due to their low auto-ignition temperature, while aromatic hydrocarbons have a low cetane number because of their high auto-ignition temperature.
I remember it having a low density, a high boiling range, and a high cetane number. You can take a look at the SH 694 standard
What was said upstairs refers to the cetane number, right? It can’t be generalized
There’s a formula, but it’s a bit complicated
Vaguely remember that the longer the straight-chain alkane chain, the higher the cetane number; the more branches there are, the lower the cetane number relatively； Olefins are similar to straight-chain alkanes, but have a slightly lower cetane number ； Aromatic hydrocarbons have a low cetane number; the presence of side chains increases the cetane number ； The above are also exceptions; I’m not sure if what I’m saying is correct. Please, experts in this field, could you provide an explanation?