Abstract:
Sound attenuation panel for aircraft having a combination of acoustic attenuation properties. The acoustic panel includes an acoustic structure having a cellular structure and a resistive skin and a backing skin, the acoustic panel also including at least one auxiliary acoustic device with cavities that is configured to produce additional acoustic absorption, the auxiliary acoustic device with cavities being attached to the acoustic structure and including adjacent chambers or cavities separated by shared walls, each of the chambers or cavities having perforations and being adapted to produce acoustic absorption. The combination of the acoustic structure and the auxiliary acoustic device with cavities enables combination of the acoustic absorption properties of these two types of element and an increased range of frequencies of the noise that can be attenuated by the acoustic panel without increasing its overall size.
Abstract:
An acoustic treatment panel in which each cell includes a plurality of conduits which extend from the porous acoustically resistive structure to the reflective layer of the acoustic treatment panel, each conduit including at least one opening set away from the porous acoustically resistive structure and configured to cause the inside and the outside of the conduit to communicate.
Abstract:
An aircraft engine air inlet lip takes an annular form about a longitudinal axis and delimits an air inlet stream, and includes: a wall having a U-shaped profile having an outer face oriented towards outside of the air inlet lip and an inner face oriented towards interior of the air inlet lip, an inner wall extending inside the wall between two zones of the inner face, so as to close an inner chamber delimited between the wall and the inner wall and filled with a gas, the inner wall having an upstream face oriented towards and a downstream face oriented away from the inner chamber, a fan configured to move the gas contained in the inner chamber, and at least one pipeline fixed to the upstream face and extending all around the air inlet lip and configured to be fed with a heat transfer fluid heated by a heat source.
Abstract:
An aircraft nacelle comprising a lip extended by an inner conduit forming an air intake, a front frame delimiting with said lip an annular channel within which hot air flows and a panel for acoustic treatment having, from outside inwardly, an acoustic resistive layer, at least one honeycomb structure and a reflective layer as well as ducts for channeling hot air, each including one inlet communicating with the annular channel and one outlet communicating with the inner conduit, wherein the panel for acoustic treatment comprises at least a stabilization chamber in the form of an annular channel with a cross-section larger than that of the ducts which extends over at least a portion of the nacelle circumference and which communicates with a plurality of ducts, the inlets and outlets not being aligned in the longitudinal direction.
Abstract:
An aircraft nacelle air intake includes sectors each having a lip forming portion, an outer panel forming portion and an inner panel forming portion. The outer panel forming portions and lip forming portions are formed by a continuous one-piece wall. At at least one junction between two adjacent sectors, an opening and a hatch are provided between the outer panel forming portions of the sectors. The inner panel forming portions and the lip forming portions of the sectors are edge to edge and fixed to each other by fixing devices accessible from the inside of the sectors and invisible from outside of the sectors. A maintenance method in which, when a zone of a sector is damaged, the sector concerned is removed as a whole and is replaced by a new of “recycled” sector is also described.
Abstract:
An air intake structure for an aircraft nacelle is disclosed. The air intake structure delimits a channel and includes a lip having a U-shaped cross section oriented towards the rear, a first sound-absorbing panel fixed behind the lip and delimiting the channel, and a second sound-absorbing panel fixed behind the first sound-absorbing panel and delimiting the channel. Each sound-absorbing panel includes a cellular core which is fixed between an inner skin pierced with holes and oriented towards the channel, and an outer skin oriented in the opposite direction, where the inner skin of the first sound-absorbing panel has a thickness greater than the thickness of the inner skin of the second sound-absorbing panel, and where each of the inner skins includes a heat source which is embedded in the mass of the inner skin.
Abstract:
An aircraft engine air inlet lip takes an annular form about a longitudinal axis and delimits an air inlet stream, and includes: a wall having a U-shaped profile having an outer face oriented towards outside of the air inlet lip and an inner face oriented towards interior of the air inlet lip, an inner wall extending inside the wall between two zones of the inner face, so as to close an inner chamber delimited between the wall and the inner wall and filled with a gas, the inner wall having an upstream face oriented towards and a downstream face oriented away from the inner chamber, a fan configured to move the gas contained in the inner chamber, and at least one pipeline fixed to the upstream face and extending all around the air inlet lip and configured to be fed with a heat transfer fluid heated by a heat source.
Abstract:
An aircraft nacelle air intake includes sectors each having a lip forming portion, an outer panel forming portion and an inner panel forming portion. The outer panel forming portions and lip forming portions are formed by a continuous one-piece wall. At at least one junction between two adjacent sectors, an opening and a hatch are provided between the outer panel forming portions of the sectors. The inner panel forming portions and the lip forming portions of the sectors are edge to edge and fixed to each other by fixing devices accessible from the inside of the sectors and invisible from outside of the sectors. A maintenance method in which, when a zone of a sector is damaged, the sector concerned is removed as a whole and is replaced by a new of “recycled” sector is also described.
Abstract:
An aircraft nacelle comprising a lip extended by an inner conduit forming an air intake, a front frame delimiting with said lip an annular channel within which hot air flows and a panel for acoustic treatment having, from outside inwardly, an acoustic resistive layer, at least one honeycomb structure and a reflective layer as well as ducts for channeling hot air, each including one inlet communicating with the annular channel and one outlet communicating with the inner conduit, wherein the panel for acoustic treatment comprises at least a stabilization chamber in the form of an annular channel with a cross-section larger than that of the ducts which extends over at least a portion of the nacelle circumference and which communicates with a plurality of ducts, the inlets and outlets not being aligned in the longitudinal direction.
Abstract:
A sound-absorbing panel includes: an inner skin traversed by holes and intended to be oriented towards a channel in which a fluid flows, a heating mat formed by strips fixed to the inner skin on the side opposite to the channel and oriented in a first direction, wherein two adjacent strips are distant from each other in order to define a slot between them, a base fixed to the strips on the side opposite to the inner skin, wherein the base includes, on the strips side, grooves extending in a second direction different from the first direction and wherein the base has, between two successive grooves, a rib, a cellular core fixed to the base on the side opposite to the strips, and an outer panel fixed to the cellular core on the side opposite to the base.