GB219664A - - Google Patents

Abstract

219,664. Naamlooze Vennootschap Instituut voor Aero-en Hydro-Dynamiek. June 28, 1923, [Convention date]. Paddle-wheels and endless band propellers; rudders. - The rudders and sails of ships and the blades of propellers have the whole or a portion of their surface skin movable around or along the surface in order to increase the reaction of the plane or blade. The skin is positively driven by a prime mover or by separate vanes acted upon by the fluid current, or is dragged round by the skin friction of the fluid current on the suction side of the plane or blade. Fig. 3 shows an aircraft plane having fixed profile members e, f and an endless flexible skin d passed over rollers b, c, the upper part moving in the direction of the airstream, and both parts assuming their correct shape under air pressure. Either or both of the profile members e, f may be omitted. Fig. 8 shows a modification in which the movable skin d is exposed only on the suction side of the plane or blade. The movable skin may be replaced by a series of rollers partially embedded in the suction side of the plane, or a single cylindrical member h, Fig. 5, may be placed between front and rear profile members e, f, or, as shown in Fig. 7, within a recess in a profile member k so as to form a tapering passage around the cylinder. Or rotating cylinders may be used alone, a cylinder rotating about a vertical axis or having a rotary skin being described for use on a ship, the direction of rotation of the surface controlling the direction of motion of the vessel. Such cylinders may be made in telescopic sections. Profiled extension pieces controlled by auxiliary surfaces may be provided with the cylinders when used as sails.