US-12618329-B2 - Unducted airfoil assembly

US12618329B2US 12618329 B2US12618329 B2US 12618329B2US-12618329-B2

Abstract

An unducted airfoil assembly includes an airfoil defining a leading edge, a trailing edge, a root, and a tip. A forward-most axial point of the leading edge is radially located at or greater than sixty percent of a tip radius of the airfoil when the airfoil is oriented at a design orientation for subsonic cruise operation.

Inventors

Kishore Ramakrishnan
Daniel Lawrence TWEEDT
Valeria Andreoli

Assignees

GENERAL ELECTRIC COMPANY

Dates

Publication Date: 20260505
Application Date: 20230330

Claims (12)

1 . An unducted airfoil assembly, comprising: an airfoil defining a leading edge and a trailing edge, a root and a tip; wherein a forward-most axial point of the leading edge is radially located between sixty percent and seventy-five percent of a tip radius of the airfoil when the airfoil is oriented at a design orientation for subsonic cruise operation, wherein the forward-most axial point of the leading edge is arcuate, wherein the forward-most axial point of the leading edge is unducted, wherein the unducted airfoil assembly is configured to generate a power loading between 80 hp/ft2 and 160 hp/ft2 at a cruise altitude during a cruise operating mode, wherein a maximum chord extending from the leading edge to the trailing edge is located at or greater than seventy-five percent of the tip radius, and wherein the maximum chord is configured to localize sweep in an acoustically sensitive portion of the airfoil.
2 . The unducted airfoil assembly of claim 1 , wherein the airfoil comprises a tip portion extending radially from the forward-most axial point to the tip, and wherein a maximum thickness of the airfoil in the tip portion for a chord extending from the leading edge to the trailing edge is located between five percent to thirty percent of the chord relative to the leading edge.
3 . The unducted airfoil assembly of claim 1 , wherein the subsonic cruise operation is a subsonic cruise flight speed at or above a flight Mach number of 0.5.
4 . The unducted airfoil assembly of claim 1 , wherein the airfoil is arranged around a longitudinal axis and rotates about the longitudinal axis in a rotational direction, and wherein a tip leading edge of the airfoil is circumferentially offset in a direction opposite the rotational direction relative to a circumferential location of the forward-most axial point.
5 . The unducted airfoil assembly of claim 1 , wherein a chordwise fractional distance from the leading edge of a maximum thickness of an airfoil section of the airfoil is minimum in a tip portion of the airfoil.
6 . The unducted airfoil assembly of claim 1 , wherein circumferential coordinates of the leading edge in a radial direction monotonically increase relative to a circumferential coordinate of the forward-most axial point of the leading edge in a direction away from a rotational direction of the airfoil at or beyond sixty percent of the tip radius of the airfoil.
7 . The unducted airfoil assembly of claim 1 , further comprising a hub defining an outer radius, wherein the airfoil extends radially outward from the hub, and wherein the outer radius of the hub is located radially at thirty percent of the tip radius of the airfoil.
8 . An unducted airfoil assembly, comprising: an airfoil defining a leading edge and a trailing edge, and further defining a root and a tip, wherein the airfoil is oriented at a design orientation for subsonic cruise operation; and a maximum chord extending from the leading edge to the trailing edge is located at or greater than seventy-five percent of a tip radius of the airfoil, wherein the unducted airfoil assembly is configured to generate a power loading between 80 hp/ft2 and 160 hp/ft2 at a cruise altitude during a cruise operating mode, wherein the maximum chord is configured to localize sweep in an acoustically sensitive portion of the airfoil, wherein a forward-most axial point of the leading edge is arcuate, wherein the forward-most axial point of the leading edge is unducted.
9 . The unducted airfoil assembly of claim 8 , wherein the airfoil defines the forward-most axial point of the leading edge and a tip portion extending from a radial location of the forward-most axial point of the leading edge to a radial location of the tip, and wherein a maximum thickness of the airfoil along a chord in the tip portion is located between five percent to thirty percent of the chord relative to the leading edge.
10 . The unducted airfoil assembly of claim 9 , wherein a chordwise fractional distance from the leading edge of a maximum thickness of an airfoil section of the airfoil is minimum in a tip portion of the airfoil.
11 . The unducted airfoil assembly of claim 9 , wherein the airfoil is arranged around a longitudinal axis and rotates about the longitudinal axis in a rotational direction, and wherein a tip leading edge of the airfoil is circumferentially offset in a direction opposite the rotational direction relative to a circumferential location of the forward-most axial point.
12 . The unducted airfoil assembly of claim 8 , further comprising a hub defining an outer radius, wherein the airfoil extends radially outward from the hub, and wherein the outer radius of the hub is located radially at thirty percent of the tip radius of the airfoil.

Description

FEDERALLY SPONSORED RESEARCH This invention was made with government support under contract number 693KA9-21-T-00003 awarded by the Federal Aviation Administration. The U.S. government may have certain rights in the invention. FIELD The present subject matter relates generally to components of a gas turbine engine, or more particularly to an unducted airfoil assembly. BACKGROUND A gas turbine engine generally includes a fan and a turbomachine arranged in flow communication with one another. Additionally, the turbomachine of the gas turbine engine generally includes, in serial flow order, a compressor section, a combustion section, a turbine section, and an exhaust section. In operation, air is provided from the fan to an inlet of the compressor section where one or more axial compressors progressively compress the air until it reaches the combustion section. Fuel is mixed with the compressed air and burned within the combustion section to provide combustion gases. The combustion gases are routed from the combustion section to the turbine section. The flow of combustion gases through the turbine section drives the turbine section and is then routed through the exhaust section, e.g., to atmosphere. The fan is driven by the turbomachine. The fan includes a plurality of circumferentially spaced fan blades extending radially outward from a rotor disk. Rotation of the fan blades creates an airflow through the inlet to the compressor section of the turbomachine, as well as an airflow over the turbomachine. BRIEF DESCRIPTION OF THE DRAWINGS A full and enabling disclosure of the presently described technology, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which: FIG. 1 is a schematic, cross-sectional view of an exemplary, unducted gas turbine engine according to various embodiments of the present subject disclosure. FIG. 2 is a schematic view of an exemplary airfoil according to various embodiments of the present disclosure. FIG. 3 is a schematic sectional view taken along line 3-3 of FIG. 2 in accordance with various embodiments of the present disclosure. FIG. 4A is a schematic view of an exemplary airfoil according to another embodiment of the present disclosure. FIG. 4B is a graph plotting a chord length of a chord as a function of a radial location of the chord, expressed as a fraction of a tip radius of the airfoil, of the exemplary airfoil of FIG. 4A according to an embodiment of the present disclosure. FIG. 5A is a schematic view of an exemplary airfoil according to another embodiment of the present disclosure. FIG. 5B is a graph plotting a chord length of a chord as a function of a radial location of the chord, expressed as a fraction of a tip radius of the airfoil, of the exemplary airfoil of FIG. 5A according to an embodiment of the present disclosure. FIG. 6 is a schematic view of an exemplary airfoil according to various embodiments of the present disclosure. FIG. 7 is a schematic view of an exemplary airfoil according to another embodiment of the present disclosure. Repeat use of reference characters in the present specification and drawings is intended to represent the same or analogous features or elements of the present subject matter. DETAILED DESCRIPTION Reference will now be made in detail to present embodiments of the disclosure, one or more examples of which are illustrated in the accompanying drawings. The detailed description uses numerical and letter designations to refer to features in the drawings. Like or similar designations in the drawings and description have been used to refer to like or similar parts of the disclosure. The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any implementation described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other implementations. Additionally, unless specifically identified otherwise, all embodiments described herein should be considered exemplary. As used herein, the terms “first” and “second” may be used interchangeably to distinguish one component from another and are not intended to signify location or importance of the individual components. The terms “forward” and “aft” refer to relative positions within a turbomachine, gas turbine engine, or vehicle and refer to the normal operational attitude of the same. For example, with regard to a gas turbine engine, forward refers to a position closer to an engine inlet and aft refers to a position closer to an engine nozzle or exhaust. The terms “upstream” and “downstream” refer to the relative direction with respect to fluid flow in a fluid pathway. For example, “upstream” refers to the direction from which the fluid flows, and “downstream” refers to the direction to which the fluid flows. The terms “coupled”, “fixed”, “attached to”, and the like refer to both direct coupling, fixing, or attaching