This Annual Meeting paper is concerned with certain of the methods used and results obtained in two investigations of fuels for high-compression aviation engines. The fuels in question are benzol and ethyl alcohol, either alone or as blended with gasoline.
The necessity of mixture-ratio runs in fuel investigations is vigorously emphasized. In that the tendencies of a fuel to detonate or preignite limit the conditions under which it may be used, methods of estimating these characteristics are discussed. Also a graphical representation has been made to illustrate the relation between compression pressure, compression-ratio, volumetric efficiency and indicated power in order that, with a given engine, the effect on detonation of changing engine conditions may be estimated.
Results characterizing the performance of the different fuels are mentioned and particular attention is directed to cases where these results are in contrast with current opinion.