Back to results
US 11,485,486 B2Granted
Active flow control for ducted fans and fan-in-wing configurations
AssigneeThe University of Toledo
InventorsChunhua Sheng, Qiuying Zhao
Life of this patent
Estimating the term…
Abstract
Systems, methods, lift fans, and aircraft involving active flow control of a ducted fan or fan-in-wing configuration are described.
Claims4
A method of conducting active flow control in a ducted fan or fan-in-wing aircraft having a fan within a duct defining a duct wall, the method comprising:
- actively sucking air through one or more suction outlets in the duct wall from a position relative to a blade tip of a rotatable blade of the fan, wherein the position is in a diffuser section of the duct under a plane defined by rotation of the blade at a quarter chord point of the blade tip and disposed at a distance from the plane approximately equal to a distance between a leading edge of the blade tip and a trailing edge of the blade tip;
- and
- directing the sucked air to an exit of the duct at a trailing edge of the duct;
- wherein the sucking is conducted at a suction speed within 15% of a speed of the blade tip.
1 more element
A method of conducting active flow control in a ducted fan or fan-in-wing aircraft having a fan within a duct defining a duct wall, the method comprising:
- passively or actively removing air from a position relative to a blade tip of a rotatable blade of the fan through one or more suction outlets in the duct wall, wherein the position is in a diffuser section of the duct under a plane defined by rotation of the blade at a quarter chord point of the blade tip and disposed at a distance from the plane approximately equal to a distance between a leading edge of the blade tip and a trailing edge of the blade tip;
- wherein the method comprises a combination of semi-annulus air extraction with zero-net mass flow and full-annulus air extraction with zero-net mass flow, wherein:
- in forward flight, the air is actively removed semi-annulusly from a windward side of the duct only under the blade, and is directed to an exit of the duct, and
- in hover, the air is actively removed in a full annulus of the duct under the blade, and is directed to an exit of the duct.
1 more element
Dependencies are inferred from the claim text.