US 11,808,281 B2
Gas turbine engine with variable pitch inlet pre-swirl features
Brandon Wayne Miller, Liberty Township, OH (US); and Arthur William Sibbach, Boxford, MA (US)
Assigned to General Electric Company, Schenectady, NY (US)
Filed by General Electric Company, Schenectady, NY (US)
Filed on Mar. 4, 2022, as Appl. No. 17/686,673.
Prior Publication US 2023/0279872 A1, Sep. 7, 2023
Int. Cl. F04D 29/54 (2006.01); F04D 19/00 (2006.01)
CPC F04D 29/542 (2013.01) [F04D 19/002 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A turbofan engine comprising:
a fan comprising a plurality of fan blades;
a turbomachine operably coupled to the fan for driving the fan, the turbomachine comprising a compressor section, a combustion section, and a turbine section in serial flow order and together defining a core air flowpath;
a nacelle surrounding and at least partially enclosing the fan, the nacelle defining a longitudinal axis;
an inlet pre-swirl feature located upstream of the plurality of fan blades, the inlet pre-swirl feature attached to or integrated into the nacelle, wherein the inlet pre-swirl feature is transitionable between a first angle with respect to the longitudinal axis of the nacelle and a second angle with respect to the longitudinal axis of the nacelle, wherein the inlet pre-swirl feature includes a leading edge, a trailing edge, and defines an opening at the trailing edge;
a blade passing sensor in communication with the plurality of fan blades; and
a controller having one or more processors and one or more memory devices, the one or more memory devices storing instructions that when executed by the one or more processors cause the one or more processors to perform operations, in performing the operations, the one or more processors are configured to:
receive an input indicating a condition of the plurality of fan blades from the blade passing sensor; and
in response to the condition of the plurality of fan blades, modulate a high pressure airflow through the opening at the trailing edge of the inlet pre-swirl feature during operation of the turbofan engine.