Abstract:
A method for manufacturing two soundproof panels of an aircraft nacelle including a duct. The manufacturing method includes a step of supplying a mold having, on a single face, a cavity for each soundproof panel, a step of producing, in the bottom of each cavity, an inner skin for being oriented towards the duct, and a curing step during which the elements present in the mold are cured in the mold. Such a method makes it possible to produce the two soundproof panels in the same mold, thus reducing the gaps between them after they have been positioned.
Abstract:
An anti-icing protection system for an aircraft engine nacelle, the nacelle comprising an inner shroud, an air intake lip forming a leading edge of the nacelle, the protection system comprising a heat exchanger device including at least one heat pipe configured to transfer heat emitted by a heat source to the inner shroud.
Abstract:
A production method for an acoustic panel comprising a step of producing a composite structure, a step of providing inserts, wherein each insert comprises a nozzle formed as a hollow cylinder with a through-bore and a cap comprising a base formed as a cylinder and a cover formed as a cone, and wherein the base is accommodated in the bore, a step of positioning the inserts in the composite structure by penetration of the cover into the composite structure so that the bore opens at one side and the other of the composite structure, a step of polymerizing during which the composite structure with the inserts is polymerized, a step of removing the caps, a first step of fixing a honeycomb structure to the polymerized composite structure, and a second step of fixing a rear skin to the honeycomb structure.
Abstract:
An aircraft nacelle comprising a first duct secured to an air intake and a second duct secured to a power plant. The two ducts are arranged end-to-end and connected by a connection. The connection comprises a bracket which extends between a first region for connecting to the power plant and a second region for connecting to the air intake, and which comprises a J-shaped profile in longitudinal planes, having at least one curved portion offset towards the outside of the nacelle with respect to the connecting regions.
Abstract:
A strip-form acoustic material, the strip having a length in a longitudinal direction, a width in a transverse direction, a thickness and axial ends. At least one of the axial ends of the strip, in an end portion of the length of the strip, the strip of material is folded in a substantially transverse plane.
Abstract:
A resistive skin shell for an acoustic panel or inner wall of an aircraft air intake, comprising an alternation, in a transverse direction, of perforated metal bands and of composite solid bands extending in a longitudinal direction. The perforated metal bands and the composite solid bands form a smooth outer face configured to be in contact with an aerodynamic stream, and a crenelated inner face. The composite solid bands have a thickness greater than the perforated metal bands. Since the perforations are provided in metal bands, which are intrinsically resistant to wear and erosion, the future proofing of the acoustic performance of the resistive skin is guaranteed. Since the composite solid bands, which are thicker, can ensure the mechanical strength of the skin, the thickness of the perforated metal bands can be reduced, allowing perforations with dimensions that are also reduced, having a lower impact on drag.
Abstract:
A cellular sound insulation structure and associated aircraft, a cell of which is provided with a diaphragm which includes a membrane having at least one orifice passing through a thickness of the membrane, and at least one tube surmounting the orifice and extending from a face of the membrane into one compartment of the cell, the tube comprising a free end, forming an acoustic outlet, which is positioned at a distance (p) from the base cross section of the cell. Also, a method for manufacturing such a cellular sound insulation structure, as well as to a tool for inserting a diaphragm into a cell. Such a cellular structure makes it possible to treat a wider acoustic frequency spectrum, and its acoustic dimensioning as well as its manufacture are simplified.
Abstract:
A method for producing an alveolar soundproofing structure in which a portion of a membrane of a diaphragm including an acoustic outlet is inserted into a hole of a perforated membrane which covers a cell of the alveolar structure, and the diaphragm is pressed into the cell with the perforated membrane becoming deformed and is fixed at that location. It also relates to the alveolar structure. Such a method enables different types of diaphragms to be inserted into different configurations of cells and enables the diaphragm to be fixed therein, in accordance with the sound frequencies to be processed.
Abstract:
An acoustic panel for an aircraft nacelle air intake comprising a resistive skin perforated by noise absorption holes and a core against which the resistive skin extends, wherein the resistive skin has a smooth visible face and a castellated rear face with alternating ribs and grooves. The noise absorption holes are formed exclusively in the grooves, i.e., in a zone where the skin is less thick, which enables the holes to have a diameter that is both greater than the thickness of the skin and small enough not to have any impact on drag. The mechanical strength of the resistive skin provided by the ribs ensures that the lesser thickness of the resistive skin in the grooves does not render the resistive skin overly flexible.
Abstract:
An anti-icing protection system for an aircraft engine nacelle, the nacelle comprising an inner shroud provided with at least one acoustic panel, an air intake lip forming a leading edge of the nacelle, the protection system comprising a heat exchanger device including at least one heat pipe configured to transfer heat emitted by a heat source to the acoustic panel or panels.