| 摘要 |
PROBLEM TO BE SOLVED: To improve fuel efficiency by improving fuel-air mixing performance in a supercharging region of an engine mounted with a supercharger.SOLUTION: In an engine air-intake device, one air-intake port 12A out of two air-intake ports 12 mounted on each cylinder has a diameter of a throat section 25 thereof smaller than that of the other air-intake port. Also, intensity of a tumble flow of intake air in a combustion chamber 6 assuming that the intake air flows into the combustion chamber 6 only through the one air-intake port 12A is increased higher than the intensity of the tumble flow of the intake air in the combustion chamber 6 assuming that the intake air flows into the combustion chamber 6 only through the other air-intake port. A tumble ratio of intake air flux in the combustion chamber 6 when the intake air supercharged by a supercharger in a supercharging region of an engine flows into the combustion chamber 6 through the two air-intake ports 12 is not less than a predetermined value.SELECTED DRAWING: Figure 9 |
