The efficient combustion of blends ERO5-7.5 under heavy load and at a high speed of 2200 [min.sup.-1] can be affected by a low cetane number of ethanol, its high latent heat for evaporation (910 kJ/kg) and auto-ignition temperature (420[degrees]C).
In contrast to ethanol, petrol demonstrates advantages linked with its threefold higher cetane number, lower auto-ignition temperature (300[degrees]C) and a calorific value better by 62.5% that in the case of using blends PRO2.5-5 translates into bmep higher by 5.6-2.7% relative to baseline parameters.
* Specifying a minimum grease auto-ignition temperature
for cooking oil of 685[degrees]F (363[degrees]C).
It was also found that the auto-ignition temperature
of the oil correlates with preignition .
Properties Diesel Acetone Butanol Molecular formula C12-C25 C3H60 C4H90H Cetane number >40 25 Oxygen content (wt %) 27.59 21.62 Density at 288 K (g/mL) 0.82-0.86 0.791 0.813 Auto-ignition temperature
(K) 503 833 658 Lower heating value (MJ/kg) 42.7 29.6 33.1 Boiling point (K) 555-561 329.2 390.8 Stoichiometric ratio 14.3 9.54 11.21 Latent heat at 298 K (kJ/kg) 270 518 582 Flammability limits (vol.
But since auto-ignition temperatures
are relatively low, it's difficult keeping a hot, compressed mixture from lighting off prematurely.