Gas turbine engine airfoil frequency design

Patent metadata

Field	Value
Publication number	US-10697304-B1
Application number	US-201815869482-A
Country	US
Kind code	B1
Filing date	Jan 12, 2018
Priority date	Jan 17, 2017
Publication date	Jun 30, 2020
Grant date	Jun 30, 2020

Abstract

A turbomachine airfoil element includes an airfoil that has pressure and suction sides spaced apart from one another in a thickness direction and joined to one another at leading and trailing edges. The airfoil extends in a radial direction a span that is in a range of 1.03-1.13 inch (26.2-28.7 mm). A chord length extends in a chordwise direction from the leading edge to the trailing edge at 50% span and is in a range of 0.93-1.03 inch (23.6-26.2 mm). The airfoil element includes at least two of a first mode with a frequency of 2182±10% Hz, a second mode with a frequency of 4966±10% Hz, a third mode with a frequency of 9675±10% Hz, a fourth mode with a frequency of 13154±10% Hz and a fifth mode with a frequency of 14056±10% Hz.

First claim

What is claimed is:

1. A turbomachine airfoil element comprising:
an airfoil having pressure and suction sides spaced apart from one another in a thickness direction and joined to one another at leading and trailing edges, the airfoil extending in a radial direction of a span that is in a range of 1.03-1.13 inch (26.2-28.7 mm);
a chord length extending in a chordwise direction from the leading edge to the trailing edge at 50% of the span is in a range of 0.93-1.03 inch (23.6-26.2 mm); and
at least three of:
a first mode has a frequency of 2182 up to ±10% Hz;
a second mode has a frequency of 4966 up to ±10% Hz;
a third mode has a frequency of 9675 up to ±10% Hz;
a fourth mode has a frequency of 13154 up to ±10% Hz; and
a fifth mode has a frequency of 14056 up to ±10% Hz;
wherein the frequencies are at a zero speed and ambient conditions, and the frequency of any given mode does not exceed the frequency of a higher order mode;
wherein the first mode is a 1EB mode, the second mode is a 1T mode, the third mode is a 2EB mode, the fourth mode is a 2T mode, and the fifth mode is a 1CWB mode, the 1EB and 2EB modes correspond to deflections substantially parallel to a thickness direction, the CWB mode corresponds to bending that is substantially normal to the thickness direction and substantially along the chordwise direction, and the 1T and 2T modes correspond to twisting about the radial direction;
wherein the airfoil element is part of an integrally bladed rotor;
wherein the airfoil comprises a nickel-based superalloy, the nickel-based superalloy has a density of 0.28-0.32 lb/in 3 (7.7-8.9 g/cm 3 ), the nickel-based superalloy has a modulus of elasticity of 27-36 Mpsi (186-248 GPa) at room temperature.

2. The element of claim 1 , wherein the frequencies are up to ±5% Hz.

3. The element of claim 1 , wherein at a minimum cruise speed of 18200-20200 rpm at Mach 0.8 at 35,000 feet:
the first mode has a frequency of 2365±10% Hz;
the second mode has a frequency of 4797±10% Hz;
the third mode has a frequency of 9526±10% Hz;
the fourth mode has a frequency of 12710±10% Hz; and
the fifth mode has a frequency of 13471±10% Hz.

4. A method of repairing an airfoil comprising the steps of:
providing an airfoil having pressure and suction sides spaced apart from one another in a thickness direction and joined to one another at leading and trailing edges, the airfoil extending in a radial direction of a span that is in a range of 1.03-1.13 inch (26.2-28.7 mm), and a chord length extending in a chordwise direction from the leading edge to the trailing edge at 50% of the span is in a range of 0.93-1.03 inch (23.6-26.2 mm), wherein the provided airfoil has at least one unrestored mode frequency that is attributable to damage to the airfoil; and
repairing the airfoil to provide at least three of:
a first mode has a frequency of 2182 up to ±10% Hz;
a second mode has a frequency of 4966 up to ±10% Hz;
a third mode has a frequency of 9675 up to ±10% Hz;
a fourth mode has a frequency of 13154 up to ±10% Hz; and
a fifth mode has a frequency of 14056 up to ±10% Hz;

wherein at least one of the first, second, third, fourth and fifth mode frequencies corresponds to a restored mode frequency that supersedes the unrestored mode frequency;
wherein the frequencies are at a zero speed and ambient conditions, and the frequency of any given mode does not exceed the frequency of a higher order mode;
wherein the first mode is a 1EB mode, the second mode is a 1T mode, the third mode is a 2EB mode, the fourth mode is a 2T mode, and the fifth mode is a 1CWB mode, the 1EB and 2EB modes correspond to deflections substantially parallel to a thickness direction, the CWB mode corresponds to bending that is substantially normal to the thickness direction and substantially along the chordwise direction, and the 1T and 2T modes correspond to twisting about the radial direction;
wherein the airfoil element is part of an integrally bladed rotor;
wherein the airfoil comprises a nickel-based superalloy, the nickel-based superalloy has a density of 0.28-0.32 lb/in 3 (7.7-8.9 g/cm 3 ), the nickel-based superalloy has a modulus of elasticity of 27-36 Mpsi (186-248 GPa) at room temperature.

5. A turbofan engine comprising:
a fan section;
a compressor section arranged fluidly downstream from the fan section;
a turbine section arranged fluidly downstream from the compressor section;
a combustor arranged fluidly between the compressor and turbine sections; and
an airfoil in at least one of the fan, compressor and turbine sections, the airfoil having:
pressure and suction sides spaced apart from one another in a thickness direction and joined to one another at leading and trailing edges, the airfoil extending in a radial direction of a span that is in a range of 1.03-1.13 inch (26.2-28.7 mm);
a chord length extending in a chordwise direction from the leading edge to the trailing edge at 50% of the span that is in a range of 0.93-1.03 inch (23.6-26.2 mm); and
at least three of:
a first mode has a frequency of 2182 up to ±10% Hz;
a second mode has a frequency of 4966 up to ±10% Hz;
a third mode has a frequency of 9675 up to ±10% Hz;
a fourth mode has a frequency of 13154 up to ±10% Hz; and
a fifth mode has a frequency of 14056 up to ±10% Hz;

wherein the frequencies are at a zero speed and ambient conditions, and the frequency of any given mode does not exceed the frequency of a higher order mode;
wherein the first mode is a 1EB mode, the second mode is a 1T mode, the third mode is a 2EB mode, the fourth mode is a 2T mode, and the fifth mode is a 1CWB mode, the 1EB and 2EB modes correspond to deflections substantially parallel to a thickness direction, the CWB mode corresponds to bending that is substantially normal to the thickness direction and substantially along the chordwise direction, and the 1T and 2T modes correspond to twisting about the radial direction;
wherein the airfoil is provided in the compressor section, the compressor section includes a low pressure compressor fluidly upstream from a high pressure compressor, the airfoil is in the high pressure compressor having eight stages, and the airfoil is part of an integrally bladed rotor;
wherein the airfoil comprises a nickel-based superalloy, the nickel-based superalloy has a density of 0.28-0.32 lb/in 3 (7.7-8.9 g/cm 3 ), the nickel-based superalloy has a modulus of elasticity of 27-36 Mpsi (186-248 GPa) at room temperature.

Assignees

• United Technologies Corp
• Raytheon Tech Corp

Inventors

• Li Haiyun
• Hunderfund Eliannah
• Nolan Sean

Classifications

• Y02T50/60

  Efficient propulsion technologies, e.g. for aircraft · CPC title

• F05D2260/96

  Preventing, counteracting or reducing vibration or noise · CPC title

• F05D2220/321

  for a special turbine stage · CPC title

• F01D5/34

  Rotor-blade aggregates of unitary construction {, e.g. formed of sheet laminae; (discs formed of sheet laminae F01D5/028; ceramic materials F01D5/284, composite materials F01D5/282)} · CPC title

• F01D5/16 Primary

  for counteracting blade vibration · CPC title