Y. Enomoto et al., HEAT-LOSSES DURING KNOCKING IN A 4-STROKE GASOLINE-ENGINE, JSME international journal. Series B, fluids and thermal engineering, 37(3), 1994, pp. 668-676
Knocking in internal combustion engines causes various problems such a
s increase in thermal loads, abnormal wear and the deterioration of pe
rformance. Even the mechanism of thermal loads alone has not been clar
ified yet. In this study, therefore, instantaneous temperatures on pis
ton top surfaces of a four-stroke gasoline engine during knocking, cau
sed by changing the spark timing and octane number, have been measured
using highly accurate thin-film thermocouples. Conditions of heat los
ses dependent on the knock intensity have been clarified from the inst
antaneous heat fluxes and coefficients of heat transfer determined fro
m measurements.