|Fuel latent heat of evaporation*||kJ/kg|
|Air specific heat||kj/°C/kg|
|Charge temperature after fuel evaporation|
Obviously, the charge temperature can look strange, but note that not all of the fuel will evaporate with heat from the air and not all of the fuel will evaporate until compression heat is added to the system. The numbers are still useful to gauge the cooling effect of different fuels and richer air:fuel mixtures. If the numbers look wrong, the post-compression temperature of the air may give a better picture of what is going on. Also note that the assumption is made that all of the fuel is evaporated. At very low air:fuel ratios on methanol for example, a fraction of the fuel may never evaporate even after combustion is complete.
* The Bosch Automotive Handbook specifies values of 380-500 kJ/kg for unleaded gasoline. 904 for ethanol, 1110 for methanol.