An air intake structure is provided with an air intake control valve
disposed in the air intake passage. The air intake control valve has a
valve element pivotally mounted at one end adjacent to a passage wall of
the air intake passage. The air intake control valve is configured to
control a gas flow based on the rotational position of the valve element.
A horizontal partitioning plate extends along the flow direction of an
intake air. The horizontal partitioning plate can be stationary or
moveable with the valve element. The valve element has a swirl-producing
notch and a vertical partitioning plate extends substantially
perpendicular to the horizontal partitioning plate from a position
corresponding to a vertical side edge of the swirl-producing notch when
the air intake control valve is fully closed. The vertical partitioning
plate can be stationary or moveable with the valve element.