Abstract: An intake duct in a cylinder head of an internal-combustion engine has a defined flow profile by which the flow rate of the gas flow is accelerated continuously, specifically up to a first intake duct segment of the intake duct which, as viewed in the flow direction, is situated in front of the valve stem. Subsequently, in a second intake duct segment, the flow rate of the gas flow is reduced continuously, whereby a lower approach flow rate of the valve is achieved. This results in an optimized volumetric efficiency which has a favorable influence on the performance and consumption of the internal-combustion engine.

Abstract: A flow duct, particularly an intake duct in an intake system and a cylinder head of an internal-combustion engine has a defined flow profile by means of which the flow rate of the gas flow is accelerated continuously, specifically until it reaches a cross-sectional transition area of the intake duct which--viewed in the flow direction--is situated upstream of a valve stem. After that, the flow rate of the gas flow is reduced whereby a lower approach flow speed of the valve is achieved. This causes an optimized volumetric efficiency which has a favorable effect on the power and the consumption of the internal-combustion engine.