Numerical Analysis of Combustion Characteristics in SI Engine Methanol Reformulated 18ICES/020
Authors
Suk-Young Lee - Pusan National University
Ku-Seob Jeong - Jinju International University Chung-Hwan Jeon - Pusan National University
Young-June Chang - Pusan National University
Abstract
This research is to estimate the possibility of using methanol reformulated fuel without modification of engine. The data obtained from the experiment are used for the numerical analysis. Methanol reformulated fuel has a higher burning speed, and heat release rate is proportional to burning speed. This is caused that the maximum heat release rate is larger and methanol reformulated fuel reaches the maximum sooner than the gasoline fuel. As engine speed increases under low-load condition, the difference in turbulent burning speed increases. On the contrary, the fuel characteristic difference decreases under high-load condition of 9.2kgf-m. The lowest turbulent burning speed is shown in unstable condition of 1500rpm and 9.2kgf-m. In the same condition, gasoline shows a larger decease than that of methanol reformulated fuel. Therefore, it is considered that methanol reformulated fuel is more suitable for operation because of better stability. Gas temperature in cylinder is higher for methanol-reformulated fuel because of higher burning speed and shorter quenching length. Therefore, it causes NO emission to increase but it produces less NO due to influence of chemical reaction dynamics and lower flame temperature respectively. Methanol reformulated fuel has higher CPL than that of gasoline fuel, and this is related to burning speed. As burning speed increases, the pressure increase rate also increases causing an abrupt combustion sound.