| 摘要 |
Element, such as a rudder, and aircraft wing, a boat keel, a hydrofoil or an airfoil or the like is adapted to move through water or air and is so designed that the water or the air is allowed to enter at the upstream edge of the element into and through a hollow space within said element and to leave said element at the trailing edge thereof, said hollow space within said element being divided into two halves by a central longitudinal partition (6) within said element, such that said element on either side of the said central partition (6) has a flow gap which, optionally, is divided into parallel passages by transverse partitions (4a, 4b, 5a-5c), the arrangement being such that the flow of water or air through and out of the gap between the central partition (6) and that side of the element which, in response to the angular deflection or profile, forms the suction side of said element, will be substantially larger than through the other gap. |
