THE effects of the combustion process and detonation on internal coolants are presented here, as well as the effect of these coolants, in turn, on engine performance.
Some of the conclusions reached by the author are:
1.
The difference between knocking and non-knocking fuels is one of degree; most fuels show evidence of pressure differentials during the combustion process, even though audible knock is not present.
2.
Complete vaporization of the internal coolant is probably not secured until combustion is under way.
3.
Water suppresses detonation by slowing down the combustion time and by cooling the end portion of the charge with water vapor contained in the end portion. Alcohol follows the same pattern when added to rich mixtures; for lean mixtures the higher antiknock qualities of the alcohol introduce a new factor.
