CN-122024680-A - Acoustic liner, broadband noise reduction device and aeroengine

Abstract

The sound liner comprises a surface acoustic resistance layer and a plurality of honeycomb core grids with different cavity depths, wherein the honeycomb core grids with different cavity depths enable the overall height of the sound liner to be uneven, communication holes are formed in the side of at least part of the honeycomb core grids to be communicated with one or more adjacent honeycomb core grids in sequence to form cavity depths with different folding times, and partition plates are further arranged on the honeycomb core grids which are communicated with each other and used for transversely dividing the honeycomb core grids. The broadband noise reduction device comprises the acoustic liner and the aeroengine. The acoustic liner can achieve a better broadband noise reduction effect under the condition of limited arrangement space.

Inventors

• XU KANGLE
• JI JIAYUAN
• Lv Yiang
• CHEN JINGNAN

Assignees

• 中国航发商用航空发动机有限责任公司

Dates

Publication Date

20260512

Application Date

20241111

Claims (10)

1. 1. The acoustic liner is characterized by comprising a surface acoustic resistance layer and a plurality of honeycomb core lattices with different cavity depths, wherein the honeycomb core lattices with different cavity depths enable the overall height of the acoustic liner to be uneven; wherein, at least part of honeycomb core grids are laterally provided with communication holes so as to be communicated with one or more adjacent honeycomb core grids in sequence, and cavity depths with different folding times are constructed; the honeycomb core cells communicated with each other are further provided with partition plates for transversely dividing the honeycomb core cells.
2. 2. The acoustic liner of claim 1 wherein the honeycomb core cells having a relatively long cavity depth communicate with the honeycomb core cells having a relatively short cavity depth through the communication holes.
3. 3. The acoustic liner of claim 1 wherein the surface acoustic resistive layer comprises one or more of a perforated plate, a wire mesh, a metal foam, an air layer.
4. 4. A sound liner according to claim 3, wherein the surface acoustic resistive layers of different species are arranged to bond to each other.
5. 5. The acoustic liner of claim 1 wherein the acoustic liner is a super-constructed acoustic liner.
6. 6. The acoustic liner of claim 1 wherein the honeycomb core and/or the surface acoustic resistive layer and/or the baffle are ceramic matrix composite or superalloy materials.
7. 7. The acoustic liner of claim 1 wherein the heights of the communication holes at different locations are staggered.
8. 8. The acoustic liner of claim 1 wherein the honeycomb core cells are hexagonal honeycomb.
9. 9. Broadband noise reduction device, characterized in that it comprises an acoustic liner according to any one of claims 1-8, which is of unequal height distribution, forms a ring-shaped structure around the engine axis, and is laid on the surface of the engine's components, along the inner surface of the nozzle.
10. 10. An aircraft engine comprising the broadband noise reducer of claim 9.

Description

Acoustic liner, broadband noise reduction device and aeroengine Technical Field The invention relates to the field of aeroengines, in particular to the field of noise reduction structures. Background To reduce engine fan noise, acoustic liners are typically placed in the intake and thrust reversals. The nacelle inlet and the thrust reverser liner are usually made of paper honeycomb or glass fiber materials, and the height of the liner is usually required to be large. At high speeds, engine combustion noise increases rapidly and is concentrated mainly in the low frequency region, while turbine noise is concentrated mainly in the high frequency region due to the increase in speed, and therefore engine core noise exhibits a broadband characteristic. Thus, when noise reduction is required for engine core noise, the noise reduction device must have both low frequency and high frequency sound absorption capabilities. However, the engine spray pipe is thin, and meanwhile, due to the limitation of accessory pipelines and the like, the internal arrangement space is limited, so that the optimal sound liner height requirement is difficult to meet. Disclosure of Invention An object of the present invention is to provide an acoustic liner capable of achieving a preferable broadband noise reduction effect under a condition that an arrangement space is limited. The acoustic liner comprises a surface acoustic resistance layer and a plurality of honeycomb core grids with different cavity depths, wherein the honeycomb core grids with different cavity depths enable the overall height of the acoustic liner to be uneven, at least part of the honeycomb core grids are provided with communication holes at the side sides so as to be communicated with one or more adjacent honeycomb core grids in sequence to form cavity depths with different folding times, and the honeycomb core grids communicated with each other are further provided with partition plates for transversely dividing the honeycomb core grids. In one or more embodiments, the honeycomb core cell having a relatively long cavity depth communicates with the honeycomb core cell having a relatively short cavity depth through the communication hole. In one or more embodiments, the surface acoustic resistive layer comprises one or more of a perforated plate of a surface layer, a wire mesh, a metal foam, an air layer. In one or more embodiments, the surface acoustic resistance layers of different species are arranged to bond to each other. In one or more embodiments, the acoustic liner is a super-constructed acoustic liner. In one or more embodiments, the honeycomb core and/or the surface acoustic resistive layer and/or the baffle are ceramic matrix composite or superalloy materials. In one or more embodiments, the heights of the communication holes at different positions are staggered. In one or more embodiments, the honeycomb cells are hexagonal cells. The invention also aims to provide a broadband noise reduction device which comprises the sound liner, wherein the broadband noise reduction device is distributed in unequal heights, forms a ring-shaped structure around the axis of the engine, is paved on the surface of a part of the engine, and is paved along the inner surface of the spray pipe. It is still another object of the present invention to provide an aircraft engine comprising the broadband noise reducer described above. On the basis of adopting the honeycomb core grids with different cavity depths, the acoustic liner unit is enabled to display the characteristic of folding cavity depths by utilizing the communication holes, so that not only are each core grid communicated, but also a U-shaped and L-shaped combined acoustic wave propagation path is constructed, and cavity depths with different folding times are constructed by sequentially communicating one or more adjacent honeycomb core grids, so that acoustic wave stroke types with different lengths are constructed, and the honeycomb core grids with different cavity depths can be also adapted to limited assembly spaces, so that the acoustic liner is distributed in uneven heights, and the problems that the traditional honeycomb acoustic liner has narrow noise reduction bandwidth and the acoustic liner height arrangement cannot realize optimal height due to the restriction of a spray pipe structure are solved. Drawings The above and other features, properties and advantages of the present invention will become more apparent from the following description in conjunction with the accompanying drawings and embodiments, in which: FIG. 1 is a partial schematic view of an aircraft engine; FIG. 2 is an enlarged view at A in FIG. 1; FIG. 3 is a partial cross-sectional view of an acoustic liner; FIG. 4 is a schematic diagram of a honeycomb cell of an acoustic liner; FIG. 5 is a schematic view of the acoustic wave travel within a contour liner; FIG. 6 is a schematic illustration of different acoustic path lengths within differen