Fan rotor for airfoil damping

Patent metadata

Field	Value
Publication number	US-11725520-B2
Application number	US-202117518897-A
Country	US
Kind code	B2
Filing date	Nov 4, 2021
Priority date	Nov 4, 2021
Publication date	Aug 15, 2023
Grant date	Aug 15, 2023

Abstract

An airfoil for use in a gas turbine engine is formed to define cavities formed in the airfoil and a passage that extends between and fluidly interconnects the cavities. The airfoil further includes damping fluid located in the cavities and the damping fluid is adapted to flow between the cavities via the passage.

First claim

What is claimed is:

1. An airfoil for use in a gas turbine engine, the airfoil comprising
an airfoil body extending radially outward relative to an axis and configured to interact with gases surrounding the airfoil body, the airfoil body having a leading edge, a trailing edge opposite the leading edge, a pressure side, and a suction side opposite the pressure side, the airfoil body formed to define a first cavity within the airfoil body and a second cavity within the airfoil body, the second cavity being spaced apart from the first cavity, the airfoil body including a damping fluid disposed within the first cavity and the second cavity, and
at least one passageway extending between and fluidly interconnecting the first cavity and the second cavity, the at least one passageway sized to allow the damping fluid to move at least partially from one of (i) the first cavity to the second cavity and (ii) the second cavity to the first cavity in response to the airfoil experiencing a modal response so as to damp the airfoil and attenuate the modal response,
wherein at least one of (i) the at least one passageway is sized such that a rate of fluid transfer at which the damping fluid moves between the first cavity and the second cavity at least one of changes a frequency of the modal response of the airfoil and adds damping and (ii) a damping fluid viscosity causes a rate of fluid transfer at which the damping fluid moves between the first cavity and the second cavity to at least one of change a frequency of the modal response of the airfoil and add damping,
wherein the first cavity includes a first passageway sidewall through which the at least one passageway opens into the first cavity, wherein the second cavity includes a second passageway sidewall through which the at least one passageway opens into the second cavity, and wherein the first passageway sidewall is spaced apart from the second passageway sidewall such that at least a portion of the airfoil body is disposed between the first passageway sidewall and the second passageway sidewall,
wherein at least one partial support wall is arranged within the first cavity and at least one partial support wall is arranged within the second cavity, and wherein each partial support wall extends at least partially from a first sidewall of a respective cavity to a second sidewall of the respective cavity opposite the first sidewall, and
wherein each partial support wall extends entirely from the first sidewall of the respective cavity to the second sidewall of the respective cavity, and wherein each partial support wall includes at least one opening through which fluid is adapted to move throughout the respective cavity.

2. The airfoil of claim 1 , wherein the airfoil body includes a blade root located adjacent to a wheel and a blade tip spaced apart radially outward from the blade root, wherein the first cavity is located radially outward of the second cavity and adjacent to the blade tip, and wherein the at least one passageway extends in a direction from the blade root to the blade tip.

3. The airfoil of claim 2 , wherein the at least one passageway includes a first passageway and a second passageway spaced apart from the first passageway in an axial direction.

4. The airfoil of claim 3 , wherein the airfoil body defines a camber line extending from the leading edge to the trailing edge, wherein each of the first passageway and the second passageway defines a center extending along a longitudinal extent of the passageway, and wherein the center of each of the first passageway and the second passageway intersects with the camber line of the airfoil body.

5. The airfoil of claim 1 , wherein the first cavity is located adjacent to the leading edge and the second cavity is located adjacent to the trailing edge such that the first cavity is spaced apart from the second cavity in the direction from the leading edge to the trailing edge.

6. The airfoil of claim 5 , wherein the at least one passageway extends in a direction from the leading edge to the trailing edge.

7. The airfoil of claim 1 , wherein the first cavity and the second cavity are arranged radially outwardly of a halfway point of a radial extent of the airfoil body.

8. The airfoil of claim 1 , wherein the airfoil body defines a camber line extending from the leading edge to the trailing edge, wherein the first cavity and the second cavity are arranged on opposing sides of the camber line, and wherein the at least one passageway extends between the first cavity and the second cavity so as to intersect the camber line.

9. A rotor assembly for use in a gas turbine engine, the rotor assembly comprising
a wheel arranged circumferentially about an axis, and
a first airfoil extending radially outwardly from the wheel relative to the axis and configured to interact with gases surrounding the first airfoil, the first airfoil including:
a first airfoil body having a leading edge, a trailing edge opposite the leading edge, a pressure side, and a suction side opposite the pressure side, the first airfoil body formed to define a first cavity within the first airfoil body and a second cavity within the first airfoil body, the second cavity being radially spaced apart from the first cavity, the first airfoil body including a first damping fluid disposed within at least one of the first cavity and the second cavity, and
at least one first passageway extending in a radial direction between and fluidly interconnecting the first cavity and the second cavity, the at least one passageway sized to allow the first damping fluid to move at least partially from one of (i) the first cavity to the second cavity and (ii) the second cavity to the first cavity in response to the first airfoil experiencing a modal response so as to damp the first airfoil and attenuate the modal response,
wherein the at least one first passageway includes a first passageway and a second passageway spaced apart from the first passageway in an axial direction,
wherein a first cross-sectional plane extending in axial and circumferential directions, when viewed from a top perspective of the first airfoil body, intersects the first passageway and the second passageway,
wherein the first airfoil body defines a camber line extending from the leading edge to the trailing edge and located in the first cross-sectional plane,
wherein each of the first passageway and the second passageway defines a central axis extending along a longitudinal extent of each respective passageway, and
wherein the central axis of each of the first passageway and the second passageway intersects with the camber line of the first airfoil body in the first cross-sectional plane.

10. The rotor of claim 9 , further comprising:
a second airfoil circumferentially offset from the first airfoil relative to the wheel, the second airfoil extending radially outwardly from the wheel relative to the axis and configured to interact with gases surrounding the second airfoil, the second airfoil including:
a second airfoil body having a leading edge, a trailing edge opposite the leading edge, a pressure side, and a suction side opposite the pressure side, the second airfoil body formed to define a third cavity within the second airfoil body and a fourth cavity within the second airfoil body, the third cavity being axially spaced apart from the third cavity, the second airfoil body including a second damping fluid disposed within at least one of the third cavity and the fourth cavity; and
at least one second passageway extending between and fluidly interconnecting the third cavity and the fourth cavity, the at least one second passageway sized to allow the second damping fluid to move at least partially from one of (i)

Assignees

• Rolls Royce Corp

Inventors

• Molnar Jr Daniel E
• Hall Christopher D

Classifications

• F01D5/16 Primary

  for counteracting blade vibration · CPC title

• F01D5/147

  Construction, i.e. structural features, e.g. of weight-saving hollow blades (F01D5/148, F01D5/16 and F01D5/20 take precedence; blade shape F01D5/141; blades with cooling or heating channels or cavities F01D5/18; heating, heat-insulating or cooling means on blades F01D5/18) · CPC title

• F05D2220/32

  in gas turbines · CPC title

• F05D2230/60

  Assembly methods · CPC title

• F05D2240/30

  Characteristics of rotor blades, i.e. of any element transforming dynamic fluid energy to or from rotational energy and being attached to a rotor · CPC title