Foil fence for hydrofoil craft
AssigneeThe Boeing Company
InventorSiebold Vanderleest
Life of this patent
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Abstract
A predetermined-sized and shaped foil-fence structure which is substantially perpendicularly mounted at the foil-tip of a hydrofoil craft and projects downward, upward or partly downward and upward from the foil-tip. The fence surfaces are generally disposed parallel to the longitudinal axis of the craft.
Claims14
A vortex control means fora a hydrofoil craft lifting foil arranged to generate lift when moved horizontally through water, the foil having an outboard tip with a predetermined chord length, said vortex control means being attached to the foil tip and comprising:
- a streamline fence extending completely along said chord length and generally vertically below said foil, the fence having an outboard surface convexly curved over substantially its entire length in the chordwise direction of the foil, and with the line of intersection of the outboard surface with any plane extending vertically normal to the chordal plane of the foil and extending parallel to the spanwise axis off the foil being a substantially straight line, a substantially planar inboard surface, a chordwise dimension corresponding to the chord length of said outboard tip of said foil, and a maximum vertical dimension as measured from the foil chord corresponding generally to one half the chord length of said outboard tip of said foil.
A vortex control means for a hydrofoil craft lifting foil arranged to generate lift when moved horizontally through water, the foil having an outboard tip with a predetermined chord length, and a movable control surface pivotally attached to the trailing edge area of the foil, the control surface extending spanwise of the foil to the tip thereof, said vortex control means comprising:
- a first streamline fence attached to the tip of the foil and extending vertically with respect to said foil approximately one half of the foil chord length at its outboard tip on either side of the chord line of the foil, and fore and aft approximately 50% of the foil chord length at its outboard tip;
- a second streamline fence attached to the tip of the said control surface, said second fence extending vertically with respect to said control surface approximately one half of the control surface chord length on either side of the chord line of the control surface, and fore and aft for approximately the entire chord length of the control surface, said second fence being mounted for movement with the control surface.
Dependencies are inferred from the claim text.