Possible Mechanisms by which Combustion-Chamber Deposits Accumulate and Influence Knock

Abstract

<div class="section abstract"><div class="htmlview paragraph">THREE mechanisms by which combustion-chamber deposits might increase the octane requirement of an engine are discussed in this paper. These are volume, catalysis, thermal insulation.</div><div class="htmlview paragraph">The experiments reported here indicate that the increase in compression ratio caused by deposit volume accounts, for 20-40% of the octane requirement increase, catalysis may not be a contributing factor, and the thermal insulating effect of the deposits is one of the major causes of deposit knocking harm.</div></div>