Abstract: An acoustic attenuation panel for a propulsion unit including a nacelle and a turbojet engine includes a cellular core disposed between an inner skin and an outer skin, called acoustic skin, the acoustic skin including a plurality of acoustic apertures, the acoustic apertures being inclined, at a non-zero inclination angle (?) relative to the direction normal to the acoustic skin, upstream with respect to the flow direction of the air or gas flow to which the panel is intended to be subjected under normal operating conditions, that is to say upstream of the propulsion unit when the panel is mounted in such a unit.

Abstract: A device for reducing the jet noise of a turbine engine includes an outer cover having an inside wall defining the outside of an annular passage for passing a bypass stream from the engine, the wall of the outer cover including a plurality of microjet circuits, each including intakes for taking a gas stream from the bypass stream flow passage and leading to a single feed duct, which in turn opens out into the trailing edge of the outer cover via at least one ejection grating suitable for splitting the intake gas stream into a plurality of gas streams of right sections of dimensions less than a right section of the feed duct.

Abstract: An acoustic attenuation panel for a propulsion unit including a nacelle and a turbojet engine includes a cellular core disposed between an inner skin and an outer skin, called acoustic skin, the acoustic skin including a plurality of acoustic apertures, the acoustic apertures being inclined, at a non-zero inclination angle (?) relative to the direction normal to the acoustic skin, upstream with respect to the flow direction of the air or gas flow to which the panel is intended to be subjected under normal operating conditions, that is to say upstream of the propulsion unit when the panel is mounted in such a unit.

Abstract: A turbomachine vane includes an electroacoustic source including two membranes fixed on a support arranged such that the membranes and the support delimit a first cavity. The membranes are arranged on two opposite sides of the first cavity between the two aerodynamic surfaces of the vane. A first of the aerodynamic surfaces includes a first region arranged facing a first of the membranes for the passage of acoustic waves. The membranes and membrane vibration device are configured such that the membranes vibrate in phase opposition and along a same emission direction by applying forces to the support such that the resultant force is approximately zero. The mechanical energy lost in the form of vane deformations due to membrane vibrations can thus be minimized.

Abstract: An acoustic treatment panel including a cellular structure core sandwiched between a solid skin and a perforated skin, and a plurality of domes made of porous fabric and extending from at least one of the skins into the insides of the cells of the cellular structure towards the other skin so as to define at least two resonant cavities inside each cell of the cellular structure.

Abstract: A device for reducing the jet noise of a turbine engine includes an outer cover having an inside wall defining the outside of an annular passage for passing a bypass stream from the engine, the wall of the outer cover including a plurality of microjet circuits, each including intakes for taking a gas stream from the bypass stream flow passage and leading to a single feed duct, which in turn opens out into the trailing edge of the outer cover via at least one ejection grating suitable for splitting the intake gas stream into a plurality of gas streams of right sections of dimensions less than a right section of the feed duct.