Patent Application
20200049075
The present embodiments generally relate to an acoustic panel and a method for making the acoustic panel. More particularly, the embodiments relate to an acoustic panel useful for acoustic or noise abatement purposes. For example acoustic or noise abatement purposes include, but are not limited to, turbomachinery, such as but not limited to, an engine and a method for making the acoustic panel.
To prevent a damage from, for example, a freeze-thaw cycle, acoustic panels may typically include slots to drain liquid. The liquid can be water and/or fuel, either for use with the device having the panels or from an exterior source from the device. In some instances, about 30% of the area of the acoustic panel can be provided with drainage slots.
However, drainage slots in the acoustic panel may have a negative effect on the desired acoustic or noise attenuation. These slots may reduce the acoustic or noise attenuation when the acoustic panel has a large amount of drainage slots that create “openings” which may not abate acoustics or noises in the device.
In addition, acoustic panel drainage slots may be provided in a default or standard pattern. These default patterns may not be able to support drainage.
In one aspect, embodiments of the present embodiment relate to an acoustic panel comprising: a face sheet comprising a plurality of openings; a back sheet opposite to the face sheet; and an intermediate layer comprising a plurality of cells each comprising a cavity and a plurality of walls extending between the face sheet and the back sheet and surrounding the cavity, the plurality of walls being provided by additive manufacturing and comprising a plurality of slots all supporting drainage of liquid.
In another aspect, embodiments of the present embodiment relate to a method for making an acoustic panel, comprising: providing a face sheet comprising a plurality of openings; providing a back sheet opposite to the face sheet; and providing an intermediate layer comprising a plurality of cells each comprising a cavity and a plurality of walls extending between the face sheet and the back sheet and surrounding the cavity, the plurality of walls being provided by additive manufacturing and comprising a plurality of slots all supporting drainage of liquid.
Optionally, the acoustic panel is useful in an engine. Optionally, the acoustic panel is useful in an aero engine. Optionally, the acoustic panel is useful in an aircraft engine. Optionally, the plurality of cavities is in fluid communication with the plurality of openings. Optionally, the plurality of slots comprises a plurality of sets of slots and the slots in each of the plurality of sets of slots are in fluid communication with each other and are aligned with a direction of the drainage of the liquid. Optionally, the slots in each of the plurality of sets of slots are aligned substantially parallel with the direction of the drainage of the liquid. Optionally, one of the plurality of cells comprises two slots in corresponding walls thereof. Optionally, one of the plurality of cells comprises at least two slots in corresponding walls thereof. Optionally, one of the plurality of cells has a cross-section of a polygon.
These and other features, aspects, and advantages of the present embodiment will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:
Unless otherwise indicated, the drawings provided herein are meant to illustrate features of embodiments of this embodiment. These features are believed to be applicable in a wide variety of systems comprising one or more embodiments of this embodiment. As such, the drawings are not meant to include all conventional features known by those of ordinary skill in the art to be required for the practice of the embodiments disclosed herein.
In the following specification and the claims, reference will be made to a number of terms, which shall be defined to have the following meanings.
The singular forms “a,” “an,” and “the” include plural references unless the context clearly dictates otherwise.
“Optional” or “optionally” means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where the event occurs and instances where it does not.
Approximating language, as used herein throughout the specification and claims, may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as “about,” “approximately,” and “substantially,” are not to be limited to the precise value specified. In at least some instances, the approximating language may correspond to the precision of an instrument for measuring the value.
As used herein, the terms “circumferential” and “circumferentially” refer to directions and orientations that extend arcuately about the centerline of the engine.
The term “coupled”, or “connected”, as used herein, is defined as coupled, or connected, directly or indirectly.
Embodiments herein relate to acoustic panels for acoustic or noise abatement purposes. Acoustic panels find exemplary and non-limiting applications where sound quality improvement and/or abatement are desirable. For example, and in no way limiting of the embodiments, acoustic panels may be used in offices, recording studies, homes, theaters, museums, restaurants, and other facilities where acoustics, noise quality and levels are a concern.
Moreover, and in no way limiting of the embodiments, acoustic panels may be used on or in machines where acoustics and noise abatement are needed or desired. These applications may include but are not limited to, manufacturing machinery, cooling and heating devices, and powerplants including those with turbomachinery, such as gas turbines, steam turbines, generators, and reciprocating engines. Acoustic panels are often useful to manage acoustics and sound quality on turbomachines, such as aero turbomachines and/or aircraft engines.
Moreover, the acoustic panels described herein comprise slots for drainage of liquid, such as water and/or fuel. The liquid may be present in the panels from openings in a face sheet of the panel. These openings are provided to facilitate drainage of liquid that is used in the operation of the device, or originates outside of the device. Regardless of the source of the liquid in the panel, the slots permit drainage of the liquid therefrom. Additionally, the slots in the acoustic panels can be provided during manufacture of the panels. The manufacturing of the panels and the formation of the slots can be by any suitable process, such as but not limited to, machining, additive manufacturing, 3D printing, forming during the molding or assembly.
The configuration of the acoustic panel herein can facilitate reduction of attenuation therein by reducing the number of slots in the acoustic panel. For example, slots that do not drain liquid can be eliminated. Additionally, the s acoustic panel configuration and the method for making the acoustic panel can increase the attenuation of the acoustic panel, increasing noise margins. Thus, it is possible to achieve desired noise levels with an acoustic panel having a reduced acoustic area and/or length, shorter duct lengths, lighter nacelle, reduced scrubbing drag, and/or lower cost, among other benefits, compared to other panels.
As used herein, the terms “face”, “back”, “intermediate”, “front”, “forward”, “aft”, “upper”, “lower”, etc., may be used in reference to the perspective of the installation and orientation of the components in the drawings, and therefore are relative terms that indicate the construction, installation and use of the components. However, it is within the scope of the embodiment that the components could be installed and/or used that markedly differs from the components shown in the drawings, or installed at other points of the engine.
The acoustic panel 21, as embodied herein will be described with respect to
Fan assembly 112 includes an array of fan blades 124 extending radially outward from a rotor disk 126. Gas turbine engine assembly 110 has an intake side 128 and an exhaust side 130. Fan assembly 112, booster 122, and turbine 120 are coupled together by a first rotor shaft 131, and compressor 114 and turbine 118 are coupled together by a second rotor shaft 132.
In operation, air flows through fan assembly 112 and a first portion 150 of the airflow is channeled through booster 122. The compressed air that is discharged from booster 122 is channeled through compressor 114 wherein the airflow is further compressed and delivered to combustor 116. Hot products of combustion (not shown in
A second portion 152 of the airflow discharged from fan assembly 112 is channeled through a bypass duct 140 to bypass a portion of the airflow from fan assembly 112 around the core gas turbine engine 113. More specifically, bypass duct 140 extends between a fan casing 142 and splitter 144. Accordingly, a first portion 150 of the airflow from fan assembly 112 is channeled through booster 122 and then into compressor 114 as described above and a second portion 152 of the airflow from fan assembly 112 is channeled through bypass duct 140 to provide thrust for an aircraft, for example. Gas turbine engine assembly 110 also includes a fan frame assembly 160 to provide structural support for fan assembly 112 and is also utilized to couple fan assembly 112 to core gas turbine engine 113.
Fan frame assembly 160 includes a plurality of outlet guide vanes 170 that typically extend substantially radially, between a radially-outer mounting flange and a radially-inner mounting flange, and are circumferentially-spaced within bypass duct 140. Guide vanes 170 serve to turn the airflow downstream from rotating blades such as fan blades 124.
To reduce noise emanating anywhere in the engine 110, such as but not limited to, in the overall fan frame assembly 160, portions thereof may be lined with noise attenuation panels, which are in the form of an acoustic panel 21, as per the embodiments herein and described with reference to
The acoustic panel 21 can be applied anywhere in the engine where noise attenuation is needed. The acoustic panel 21 can be configured in an arcuate form, for example, having a double curvature configuration. This configuration is embodied in structural parts of the engine 110 illustrated in
Referring now to
The plurality of openings 23 in the face sheet 23 provide fluid communication between the cells 26 of the cellular intermediate layer 25 and the front face of the face sheet 22. Fluid can pass through one or more of the plurality of openings 23 in the face sheet 22 and enter into the cells 26 of the cellular intermediate layer 25.
The plurality of openings 23 of the face sheet 22 of the acoustic panel 21 have any cross-section (such as the circular cross-section as illustrated in
To provide for noise attenuation over a wide range of frequencies, the geometry and distribution of one or more of the plurality of openings 23 may be modified. For example and not limiting of the embodiments, one or more of the plurality of openings 23 may be positioned as an array of openings, and with an opening size and shape that vary over the face sheet 22. An opening size variation may provide differentiated attenuating performance across the acoustic panel 21.
The plurality of openings 23 may be produced by any appropriate manufacturing process. Exemplary and non-limiting processes include at least one of additive manufacturing, 3D printing, mechanical drilling, laser beam drilling, and/or electron beam drilling. The plurality of openings 23 may be produced prior to the face sheet 22, the cellular intermediate layer 25 and the back sheet 24 are joined. However, depending on the manufacturing process, the formation of the plurality of openings may at any appropriate.
The face sheet 22 is coupled to an upper face of the cellular intermediate layer 25. The coupling can be by an adhesive, by the manufacturing processing or other suitable coupling system. The back sheet 24 may be unperforated and made from an impermeable sheet material. The back sheet 24 may also be connected by be by an adhesive, by the manufacturing processing or other suitable coupling system to a lower face of the cellular intermediate layer 25. The cells 26 of the cellular intermediate layer 25 are open-ended and juxtaposed. Also, the plurality of cavities 260 defined thereby may be in fluid communication with the plurality of openings 23, as illustrated in
In other exemplary non-limiting embodiments, one or more of the plurality of cells 26 may have a polygonal cross-section 264. For example, and not intending to limit the embodiments in any way, one or more of the plurality of cells 26 may have hexagonal cross sections to provide a honeycomb configuration of the intermediate layer 25. Alternatively, the one or more of the plurality of cells 26 may have juxtaposed cells of other polygonal cross-sections other than but including hexagonal positioned in the acoustic panel, with cells of different sizes and shapes adjacent each other. For example, one or more of the plurality of cells 26 may be rectangular, one or more of the plurality of cells 26 may be triangular, one or more of the plurality of cells 26 may be hexagonal, one or more of the plurality of cells 26 may be octagonal, and so forth. In essence, the configuration and polygonal shapes of the one or more of the plurality of cells 26 can take numerous and non-limiting shapes, arrangements, and formations.
In a non-limiting embodiment, the slots 262 in the walls 261 can allow fluids, such as water and/or fuel, to drain from the acoustic panel 21, in the direction of arrows Y. Following the fluid flow, the fluid enters the acoustic panel 21 through the plurality of holes 23 in the face sheet 22, as shown by arrow X. As the fluid enters the intermediate layer 25 it enters one of the plurality of cells 26. From that cell 26 to which the fluid enters, it can then flow through slots 262 as illustrated in
As illustrated in
Alternatively, the plurality of sets of slots 263 can be aligned with line S, which connects slots 262 of two adjacent cells 26 in one set of slots 263. Line S defines an acute angle α with respect to the direction D of the drainage of the liquid.
Referring to
In an alternate method, Steps 41, 42 and 43 may be simultaneously provided/formed in a contemporaneously to form the acoustic panel 21. Exemplary simultaneous methods include, but are not limited to, forming the acoustic panel 21 by molding, 3D printing, additive manufacturing, and the similar simultaneous manufacturing processes.
This written description uses examples to disclose the embodiments, including the best mode, and also to enable any person skilled in the art to practice the embodiments, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the embodiment is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.
