US-12624637-B2 - CMC airfoil with circumventing cooling passage

US12624637B2US 12624637 B2US12624637 B2US 12624637B2US-12624637-B2

Abstract

An airfoil includes an airfoil section that defines a trailing edge region that includes a trailing edge. The airfoil section is formed of a ceramic matrix composite that includes core fiber plies and skin fiber plies. The core fiber plies define a radial tube that has a radiused end in the trailing edge region. The skin fiber plies wrap around the core fiber plies and a filler element in the trailing edge region is aft of the internal cavity and is sandwiched between the skin fiber plies on the pressure side and the skin fiber plies on the suction side. There is at least one cooling passage that includes a first, inlet orifice section that opens to the internal cavity at a location forward of the radiused end and that extends through the core fiber plies, and a second, outlet orifice section that extends through the trailing edge.

Inventors

Jonas Banhos
James T. Roach
Russell Kim
Raymond Surace

Assignees

RTX CORPORATION

Dates

Publication Date: 20260512
Application Date: 20231004

Claims (15)

1 . An airfoil comprising: an airfoil section defining pressure and suction sides, a leading edge, and a trailing edge region including a trailing edge, the airfoil section being formed of a ceramic matrix composite that includes fiber plies disposed in a ceramic matrix, the fiber plies including: core fiber plies defining a radial tube that circumscribes an internal cavity, the radial tube having a radiused end in the trailing edge region, and skin fiber plies defining an exterior of the airfoil section and wrapping around the core fiber plies from the pressure side of the trailing edge region, through the leading edge, and to the suction side of the trailing edge region; a filler element in the trailing edge region aft of the internal cavity and sandwiched between the skin fiber plies on the pressure side and the skin fiber plies on the suction side; and at least one cooling passage including: a first, inlet orifice section opening to the internal cavity at a location forward of the radiused end and extending through the core fiber plies, wherein there is a number N of the core fiber plies each having a ply thickness t, and the location is forward of the radiused end by a distance D that is greater than the product of N, t, and a multiplier X that is from five to ten, a second, outlet orifice section extending through the trailing edge, and a third, intermediate section connecting the first and second sections, and the third section laterally bound by at least one of the skin plies.
2 . The airfoil as recited in claim 1 , wherein the third section is also laterally bound by the filler element.
3 . The airfoil as recited in claim 2 , wherein the filler element includes a filler core and a filler skin ply on the filler core, and the filler skin ply partially bounds the third section.
4 . The airfoil as recited in claim 2 , wherein the third section is bound by at least two of the skin plies.
5 . The airfoil as recited in claim 1 , wherein the location is toward the suction side of the core fiber plies.
6 . The airfoil as recited in claim 1 , wherein the at least one cooling passage includes multiple cooling passages, for a first portion of the multiple cooling passages the location is toward the suction side of the core fiber plies, and for a second portion of the multiple cooling passages the location is toward the pressure side of the core fiber plies.
7 . The airfoil as recited in claim 6 , wherein the multiple cooling passages each include a third, intermediate section connecting the first and second sections, the third section of the first portion of the multiple cooling passages extending adjacent the suction side between at least one of the skin plies and the filler element, and the third section of the second portion of the multiple cooling passages extending adjacent the pressure side between at least one of the skin plies and the filler element.
8 . The airfoil as recited in claim 1 , wherein an inner surface of the at least one of the skin plies bounds the third section, the inner surface facing toward the core fiber plies.
9 . The airfoil as recited in claim 8 , wherein the at least one cooling passage is a single cooling passage, the first inlet orifice section is a single inlet orifice, and the second outlet orifice section is a single outlet orifice.
10 . A gas turbine engine comprising: a compressor section; a combustor in fluid communication with the compressor section; and a turbine section in fluid communication with the combustor, the turbine section having airfoils each including: an airfoil section defining pressure and suction sides, a leading edge, and a trailing edge region including a trailing edge, the airfoil section being formed of a ceramic matrix composite that includes fiber plies disposed in a ceramic matrix, the fiber plies including: core fiber plies defining a radial tube that circumscribes an internal cavity, the radial tube having a radiused end in the trailing edge region, and skin fiber plies defining an exterior of the airfoil section and wrapping around the core fiber plies from the pressure side of the trailing edge region, through the leading edge, and to the suction side of the trailing edge region; a filler element in the trailing edge region aft of the internal cavity and sandwiched between the skin fiber plies on the pressure side and the skin fiber plies on the suction side; and at least one cooling passage including: a first, inlet orifice section opening to the internal cavity at a location forward of the radiused end and extending through the core fiber plies, wherein there is a number N of the core fiber plies each having a ply thickness t, and the location is forward of the radiused end by a distance D that is greater than the product of N, t, and a multiplier X that is from five to ten, a second, outlet orifice section extending through the trailing edge, and a third, intermediate section connecting the first and second sections, and the third section laterally bound by at least two of the skin plies.
11 . The gas turbine engine as recited in claim 10 , wherein the location is toward the suction side of the core fiber plies.
12 . The gas turbine engine as recited in claim 10 , wherein the at least one cooling passage includes multiple cooling passages, for a first portion of the multiple cooling passages the location is toward the suction side of the core fiber plies, and for a second portion of the multiple cooling passages the location is toward the pressure side of the core fiber plies.
13 . The gas turbine engine as recited in claim 12 , wherein the multiple cooling passages each include a third, intermediate section connecting the first and second sections, the third section of the first portion of the multiple cooling passages extending adjacent the suction side between at least one of the skin plies and the filler element, and the third section of the second portion of the multiple cooling passages extending adjacent the pressure side between at least one of the skin plies and the filler element.
14 . A method of fabricating an airfoil that has an airfoil section defining pressure and suction sides, a leading edge, and a trailing edge region including a trailing edge, the method comprising: forming a fiber preform by: laying-up core fiber plies to form a radial tube that circumscribes an internal cavity, the radial tube having a radiused end in the trailing edge region; laying-up skin fiber plies to wrap around the core fiber plies to form an exterior of the airfoil section, the skin fiber plies wrap from the pressure side of the trailing edge region, through the leading edge, and to the suction side of the trailing edge region; arranging a filler element in the trailing edge region aft of the internal cavity and sandwiched between the skin fiber plies on the pressure side and the skin fiber plies on the suction side; at least one cooling passage being formed in the airfoil section by a first, inlet orifice section that extends through the core fiber plies and that opens to the internal cavity at a location forward of the radiused end, wherein there is a number N of the core fiber plies each having a ply thickness t, and the location is forward of the radiused end by a distance D that is greater than the product of N, t, and a multiplier X that is from five to ten, a second, outlet orifice section that extends through the trailing edge, and a third, intermediate section connecting the first and second sections, the third section laterally bound by at least one of the skin plies; and densifying the fiber preform with a ceramic matrix to form a ceramic matrix composite.
15 . The method as recited in claim 14 , wherein, prior to the densifying, the core fiber plies and the skin fiber plies contain no ceramic matrix.

Description

BACKGROUND A gas turbine engine typically includes a fan section, a compressor section, a combustor section and a turbine section. Air entering the compressor section is compressed and delivered into the combustion section where it is mixed with fuel and ignited to generate a high-pressure and temperature core gas flow. The high-pressure and temperature core gas flow expands through the turbine section to drive the compressor and the fan section. The compressor section may include low and high pressure compressors, and the turbine section may also include low and high pressure turbines. Airfoils in the turbine section are typically formed of a superalloy and may include thermal barrier coatings to extend temperature capability and lifetime. Ceramic matrix composite (“CMC”) materials are also being considered for airfoils. Among other attractive properties, CMCs have high temperature resistance. Despite this attribute, however, there are unique challenges to implementing CMCs in airfoils. SUMMARY An airfoil according to an example of the present disclosure includes an airfoil section that defines pressure and suction sides, a leading edge, and a trailing edge region including a trailing edge. The airfoil section is formed of a ceramic matrix composite that includes fiber plies disposed in a ceramic matrix. The fiber plies have core fiber plies that define a radial tube that circumscribes an internal cavity. The radial tube has a radiused end in the trailing edge region, and skin fiber plies define an exterior of the airfoil section and wrap around the core fiber plies from the pressure side of the trailing edge region, through the leading edge, and to the suction side of the trailing edge region. There is a filler element in the trailing edge region aft of the internal cavity and sandwiched between the skin fiber plies on the pressure side and the skin fiber plies on the suction side. At least one cooling passage has a first, inlet orifice section that opens to the internal cavity at a location forward of the radiused end and extends through the core fiber plies, and a second, outlet orifice section that extends through the trailing edge. In a further embodiment of any of the foregoing embodiments, the at least one cooling passage includes a third, intermediate section connecting the first and second sections, and the third section is bound by at least one of the skin plies and the filler element. In a further embodiment of any of the foregoing embodiments, the filler element includes a filler core and a filler skin ply on the filler core, and the filler skin ply partially bounds the third section. In a further embodiment of any of the foregoing embodiments, the third section is bound by at least two of the skin plies. In a further embodiment of any of the foregoing embodiments, the fiber plies include a number N of the core fiber plies each having a ply thickness t, and the location is forward of the radiused end by a distance D that is greater than the product of N, t, and a multiplier X that is from five to ten. In a further embodiment of any of the foregoing embodiments, the location is toward the suction side of the core fiber plies. In a further embodiment of any of the foregoing embodiments, the at least one cooling passage includes multiple cooling passages, for a first portion of the multiple cooling passages the location is toward the suction side of the core fiber plies, and for a second portion of the multiple cooling passages the location is toward the pressure side of the core fiber plies. In a further embodiment of any of the foregoing embodiments, the multiple cooling passages each include a third, intermediate section connecting the first and second sections. The third section of the first portion of the multiple cooling passages extend adjacent the suction side between at least one of the skin plies and the filler element, and the third section of the second portion of the multiple cooling passages extending adjacent the pressure side between at least one of the skin plies and the filler element. A gas turbine engine according to an example of the present disclosure includes a compressor section, a combustor in fluid communication with the compressor section, and a turbine section in fluid communication with the combustor. The turbine section has airfoils according to any of the foregoing embodiments. Also disclosed is a method of fabricating an airfoil according to any of the foregoing embodiments. In a further embodiment of any of the foregoing embodiments, prior to densifying, the core fiber plies and the skin fiber plies contain no ceramic matrix. The present disclosure may include any one or more of the individual features disclosed above and/or below alone or in any combination thereof. BRIEF DESCRIPTION OF THE DRAWINGS The various features and advantages of the present disclosure will become apparent to those skilled in the art from the following detailed description. The drawings th