Defrosting and acoustic treatment device for an air intake lip of a turbojet engine nacelle

Patent metadata

Field	Value
Publication number	US-12269604-B2
Application number	US-202016991636-A
Country	US
Kind code	B2
Filing date	Aug 12, 2020
Priority date	Feb 12, 2018
Publication date	Apr 8, 2025
Grant date	Apr 8, 2025

Abstract

A defrosting and acoustic treatment device for an air intake lip of a turbojet engine nacelle includes an embossed acoustic structure that delimits a plurality of acoustic cells, each acoustic cell being delimited by an independent peripheral wall that allows a flow of de-icing air to flow around each acoustic cell.

First claim

What is claimed is:

1. A nacelle for a turbojet engine, the nacelle comprising:
an air intake lip including an acoustic skin;
a defrosting and acoustic treatment device for the air intake lip, the defrosting and acoustic treatment device comprising a waffle acoustic structure adapted to bear on the acoustic skin of the air intake lip, and delimiting a plurality of acoustic cells, each acoustic cell being delimited by an independent peripheral wall that defines a top surface opposing the acoustic skin, each acoustic cell being tapered from the acoustic skin to the top surface such that the top surface of each acoustic cell is spaced apart and disconnected from the top surfaces of adjacent ones of the acoustic cells to define a space therebetween, a defrost air being allowed to be directed into the space from above the top surface to flow around each acoustic cell,
wherein the waffle acoustic structure delimits at least two rows of acoustic cells connected together by at least one connecting portion adapted to bear on the acoustic skin of the air intake lip, the acoustic cells being made in one piece with the at least one connecting portion, each connecting portion being a strip that has a main surface parallel to the acoustic skin and matching a shape of the air intake lip, and
wherein the acoustic skin includes perforations, the perforations being covered by each of the acoustic cells and the at least one connecting portion.

2. The nacelle according to claim 1 , wherein each row of the acoustic cells has an annular shape about a longitudinal central axis (A).

3. The nacelle according to claim 1 , wherein the waffle acoustic structure has a monolithic annular shape.

4. The nacelle according to claim 1 , wherein the waffle acoustic structure has a shape of several monolithic angular sectors.

5. The nacelle according to claim 1 , wherein each acoustic cell has a pyramidal shape.

6. The nacelle according to claim 1 , wherein the defrosting and acoustic treatment device further comprises at least one deflector configured to guide the defrost air to flow toward the waffle acoustic structure.

7. The nacelle according to claim 1 , wherein the defrosting and acoustic treatment device further comprises a tube for distributing the defrost air, the tube having a toroidal shape about a longitudinal central axis (A) and delimiting a plurality of slots forming injectors, the plurality of slots being arranged opposite the plurality of acoustic cells to direct the defrost air between the acoustic cells.

8. The nacelle according to claim 1 , wherein adjacent two of the acoustic cells and a portion of the strip disposed therebetween define a valley.

9. The nacelle according to claim 1 , wherein the defrosting and acoustic treatment device further comprises at least one connecting strip extending in a longitudinal direction of the nacelle to connect the acoustic cells in different rows, the connecting strip being perpendicular to the connecting portion.

10. The nacelle according to claim 1 , wherein the waffle acoustic structure is configured to allow the top surface and a tapered surface of each of the acoustic cells and the at least one connecting portion to be exposed to the defrost air such that the defrost air is directed from above the top surface to flow around each of the acoustic cells and to allow heat from the defrost air to be transmitted through the top surface and the tapered surface of each of the acoustic cells and through the at least one connecting portion to the acoustic skin by conduction.

11. A method for manufacturing a defrosting and acoustic treatment device for an air intake lip of a turbojet engine nacelle, wherein the defrosting and acoustic treatment device comprises a waffle acoustic structure delimiting a plurality of acoustic cells, each acoustic cell being delimited by an independent peripheral wall that defines a top surface opposing an acoustic skin, each acoustic cell being tapered from the acoustic skin to the top surface such that the top surface of each acoustic cell is spaced apart and disconnected from the top surfaces of adjacent ones of the acoustic cells to define a space therebetween, a defrost air being allowed to be directed into the space from above the top surface to flow around each acoustic cell, the waffle acoustic structure delimiting at least two rows of acoustic cells connected together by at least one connecting portion adapted to bear on the acoustic skin of the air intake lip, the acoustic cells being made in one piece with the at least one connecting portion, each connecting portion being a strip that has a main surface parallel to the acoustic skin and matching a shape of the air intake lip, the acoustic skin including perforations, the perforations being covered by each of the acoustic cells and the at least one connecting portion,
wherein the method comprises at least one manufacturing process producing the waffle acoustic structure made in one piece into a monolithic part.

Assignees

• Safran Nacelles

Inventors

• Digeos Virginie Emmanuelle Anne Marie
• Boileau Patrick

Classifications

• F05D2220/323

  for aircraft propulsion, e.g. jet engines · CPC title

• F02C7/047

  Heating to prevent icing · CPC title

• B64D2033/0286

  for turbofan engines · CPC title

• B64D2033/0233

  comprising de-icing means · CPC title

• B64D2033/0206

  comprising noise reduction means, e.g. acoustic liners · CPC title