US 12,320,315 B2
Unducted single rotor engine and method for operation
Syed Arif Khalid, West Chester, OH (US); and Andrew Breeze-Stringfellow, Montgomery, OH (US)
Assigned to General Electric Company, Evendale, OH (US)
Filed by General Electric Company, Schenectady, NY (US)
Filed on Oct. 15, 2020, as Appl. No. 17/071,018.
Claims priority of provisional application 62/915,364, filed on Oct. 15, 2019.
Prior Publication US 2021/0108595 A1, Apr. 15, 2021
Int. Cl. F02K 1/66 (2006.01); F01D 7/00 (2006.01); F01D 17/16 (2006.01); F02C 6/20 (2006.01); F02K 1/76 (2006.01); F04D 27/02 (2006.01); F04D 29/32 (2006.01); F04D 29/56 (2006.01)
CPC F02K 1/66 (2013.01) [F01D 17/162 (2013.01); F02C 6/206 (2013.01); F02K 1/76 (2013.01); F04D 27/0246 (2013.01); F04D 29/323 (2013.01); F04D 29/563 (2013.01); F01D 7/00 (2013.01); F05D 2220/325 (2013.01); F05D 2260/70 (2013.01); F05D 2270/05 (2013.01); F05D 2270/051 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A propulsion system comprising:
a rotor assembly configured to rotate about an engine centerline axis, the rotor assembly comprising a plurality of blades, each blade of the plurality of blades configured to rotate about a respective blade pitch angle axis, wherein the rotor assembly defines a rotor plane; and
a vane assembly positioned in aerodynamic relationship with the rotor assembly, the vane assembly comprising a plurality of vanes including a first vane, a second vane, and a third vane, wherein the first vane is circumferentially adjacent to the second vane with respect to a circumferential direction defined about the engine centerline axis, and the third vane is circumferentially adjacent to the second vane with respect to the circumferential direction, wherein at least one of the plurality of vanes is configured to rotate about a respective vane pitch axis, wherein the first vane, the second vane, and the third vane of the plurality of vanes are not evenly spaced from each other in the circumferential direction;
a controller configured to execute operations, the operations comprising:
rotating each blade of the plurality of blades in a first direction about the respective blade pitch angle axis to a reverse thrust position according to an asynchronous blade pitching schedule, wherein a leading edge of the respective blade is located aft of a trailing edge of the respective blade at a radial span location when in the reverse thrust position;
rotating at least one of the plurality of vanes about the respective vane pitch axis in a second direction opposite the first direction when the plurality of blades are in the reverse thrust position to increase an amount of reverse thrust generated by the propulsion system, and to adjust a loading at the rotor assembly, wherein rotating the at least one of the plurality of vanes about the respective vane pitch axis in the second direction is done independently from the blade pitch rotation of the plurality of blades; and
rotating the at least one of the plurality of vanes about the respective vane pitch axis in the first direction when the plurality of blades are in the reverse thrust position to reduce the amount of reverse thrust generated by the propulsion system, and to adjust a loading at the rotor assembly, wherein rotating the at least one of the plurality of vanes about the respective vane pitch axis in the first direction is done independently from the blade pitch rotation of the plurality of blades.