Cylinder Performance-Compression Ratio and Mechanical Octane-Number Effects 500192
DATA obtained with a cylinder of passenger-car-engine size are discussed. Compression ratios of from 5.7 to 15 to 1 have been explored rather completely with four types of combustion chamber. The investigation of this compression ratio range has included the determination of fuel economy at 1200 and 3000 rpm, with particular emphasis on part-load economy.
In order to make it possible to compare results over a wide range of compression ratios, fuel economy data are presented in terms of relative thermal efficiency. Knocking data are presented in terms of air density in the combustion chamber and in terms of an empirical equivalent of air density. It is shown that, over a considerable compression ratio range, the knock-limited combustion-chamber air density on isooctane or 80 octane-20 heptane is independent of compression ratio.
It is shown that turbulence has rather considerable effects in improving part-load economy and knock-limited performance. Turbulence is also shown to reduce engine severity.
Citation: Heron, S. and Felt, A., "Cylinder Performance-Compression Ratio and Mechanical Octane-Number Effects," SAE Technical Paper 500192, 1950, https://doi.org/10.4271/500192. Download Citation
Author(s):
S.D. Heron, A.E. Felt
Affiliated:
Ethyl Corp.
Pages: 45
Event:
Pre-1964 SAE Technical Papers
ISSN:
0148-7191
e-ISSN:
2688-3627
Related Topics:
Combustion chambers
Fuel economy
Engine cylinders
Turbulence
Knock
SAE MOBILUS
Subscribers can view annotate, and download all of SAE's content.
Learn More »
