Combustion-Chamber Deposition and Knock

530239

01/01/1953

Event
Pre-1964 SAE Technical Papers
Authors Abstract
Content
THIS paper discusses a number of factors involved in the problem of octane-number requirement increase due to combustion-chamber deposits. A laboratory single-cylinder engine test procedure, which evaluates the effects of various fuel and oil factors, is presented with data showing its correlation with passenger-car operation under light-duty, city-driving conditions.
The influence of engine operating conditions during accumulation of deposits and the importance of engine conditions selected to evaluate the magnitude of the requirement increase are illustrated. It is indicated that organic materials formed from both fuel and oil are of major importance in deposit formation.
Data are presented which show that tel added to pure hydrocarbons of different chemical types may have different effects. It is shown that the carbon/hydrogen ratio of leaded pure hydrocarbons influences the amount and composition of the deposit formed. Among leaded commercial gasolines there appears to be little effect of changes in hydrocarbon composition, although there is a trend toward smaller requirement increase as fuel endpoint is reduced.
Similarly, removal of heavy ends from lubricating oils tends to lessen requirement increase, and the magnitude of this effect is dependent on the contribution of the fuel to the organic portion of the deposit. Maximum effects are observed when clean-burning leaded isooctane is used as the fuel.
Combustion-chamber design and deposit location influence the magnitude of the requirement increase.
Meta TagsDetails
DOI
https://doi.org/10.4271/530239
Pages
17
Citation
Gibson, H., Hall, C., and Hirschler, D., "Combustion-Chamber Deposition and Knock," SAE Technical Paper 530239, 1953, https://doi.org/10.4271/530239.
Additional Details
Publisher
Published
Jan 1, 1953
Product Code
530239
Content Type
Technical Paper
Language
English