Parametrical Investigation of Heat Transfer with Fast Response Thermocouple in SI Engine

This paper seeks to examine the characteristics and importance of the heat transfer phenomena in combustion chamber walls. In-cylinder pressure and combustion chamber wall temperature (Tw) were measured under motored and fired conditions in a spark-ignition (SI) engine. Parameters were measured at a constant engine speed (1,500rpm), at different ignition timings, and same phi=1.0, separately for LPG, gasoline, or hydrogen. Cooling loss and heat release were investigated with different heat transfer equations for all three fuels. Also, the cooling loss of hydrogen was compared with fossil fuels to investigate the differences in heat transfer. The values for a correction constant required for each fuel were determined using different heat transfer equations. The findings of this study suggest that the proposed model has better prediction results than Eichelberg's heat transfer coefficient equation and Burnt's specific heat ratio equation for all ignition timings and fuels.