Abstract: A porous skin including strips and an acoustic attenuation panel. The porous skin (1) includes of strips (2) arranged transversely to a fluid flow (E) and which successively overlap each other laterally, each strip (2) upstream of said fluid flow (E) overlapping the downstream strip or strips (2), each of the strips (2) including at least one lateral edge comprising a contour defining a line with deviations, namely a broken line and/or a curved line, and the arrangement of the strips (2) and the contour or contours of their lateral edges being configured to form openings (11) between the strips (2) connecting an external face of the porous skin (1) to an internal face of said porous skin (1) and to prevent the fluid flow (E) from penetrating into said openings (11), the porous skin (1) thus being adapted to have sound waves pass through it while preventing the fluid flow (E) from passing through it.

Abstract: A method for manufacturing a cellular structure having first and second faces, rows of cells each alternatingly having first cells, which are open in the direction of the first face, second cells, which are open in the direction of the second face, and also third cells formed between each row of cells, each row of cells comprising first and second strips of material placed against one another. The first and second strips of material are shaped by bending. By contrast to plastic deformation, shaping by bending makes it possible to expand the choice of materials and thicknesses for the first and second strips of material. An advantageous cellular structure is thus obtained as well as an acoustic absorption coating comprising such a cellular structure.

Abstract: A soundproofing coating with a cellular structure having several structures connected in a transverse direction, each formed by connecting a first longitudinal strip with a second longitudinal strip. Each structure has, successively in the longitudinal direction, 1) a first cavity, the cross-section of which narrows gradually in the thickness of the coating until it closes, 2) a first connection of two walls, respectively of the first strip and the second strip, in contact with each other over part of the thickness of the coating, which provides a passage between the first cavity and a second cavity that thus form a Helmholz resonator, 3) the second cavity, the cross-section of which gradually increases in the thickness of the coating and which is closed by a closing sheet, and 4) a second connection of two walls.

Abstract: A sound-proofing covering comprising a cellular structure, each cell of which comprises a duct extending at least between the first face and the second face of the covering. The duct is formed between an outer wall and an inner wall of the cell and has a restriction of its cross section. The outer and inner walls have rounded forms, without sharp edges. The cell comprises a cavity in which the duct emerges. Thus, each cell forms a resonator comprising a neck formed by the duct and the cavity. Each cell is conformed such that the duct and the cavity are formed on either side of the inner wall. Such a covering is particularly suitable for reducing acoustic waves in aircraft engine plant nacelles, particularly in the low frequencies.

Abstract: A sound-proofing covering comprising a cellular structure, each cell of which comprises a duct extending at least between the first face and the second face of the covering. The duct is formed between an outer wall and an inner wall of the cell and has a restriction of its cross section. The outer and inner walls have rounded forms, without sharp edges. The cell comprises a cavity in which the duct emerges. Thus, each cell forms a resonator comprising a neck formed by the duct and the cavity. Each cell is conformed such that the duct and the cavity are formed on either side of the inner wall. Such a covering is particularly suitable for reducing acoustic waves in aircraft engine plant nacelles, particularly in the low frequencies.

Abstract: Device for localizing acoustic sources and/or measuring their intensities, intended in particular to be used in confined spaces, the device including at least one acoustic antenna having a first series of microphones delimiting a first volume, and a second series of microphones delimiting a volume containing at least substantially the first series of microphones.

Abstract: Device for localizing acoustic sources and/or measuring their intensities, intended in particular to be used in confined spaces, the device including at least one acoustic antenna having a first series of microphones delimiting a first volume, and a second series of microphones delimiting a volume containing at least substantially the first series of microphones.