Abstract: An apparatus is provided that includes a structure. This structure includes a first skin, a second skin and a cellular core connected to the first skin and the second skin. The cellular core includes a cantilevered damper and an internal cavity between the first skin and the second skin. The cantilevered damper projects into the internal cavity. The cantilevered damper includes a plurality of damper masses and a plurality of damper arms interconnecting the plurality of damper masses together.

Abstract: An apparatus is provided for an aircraft propulsion system. This apparatus includes a cascade structure including a thrust reverser cascade and a flow disruptor. The thrust reverser cascade extends longitudinally between a cascade forward end and a cascade aft end. The thrust reverser cascade extends laterally between a cascade first side and a cascade second side. The thrust reverser cascade extends radially between an inner face and an outer face. The thrust reverser cascade includes a plurality of vanes arranged in a longitudinally extending array along the inner face. The flow disruptor is arranged at the cascade inner face and forward of the vanes. The flow disruptor is configured to disrupt boundary layer air flowing towards the vanes.

Abstract: An apparatus is provided for an aircraft propulsion system. This apparatus includes a thrust reverser cascade extending longitudinally between a cascade forward end and a cascade aft end. The thrust reverser cascade extends laterally between a cascade first side and a cascade second side. The thrust reverser cascade extends radially between a cascade inner face and a cascade outer face. The thrust reverser cascade includes a plurality of vanes arranged in a longitudinally extending array. The vanes include a first vane and a second vane. A leading edge of the first vane is disposed on the cascade inner face. A leading edge of the second vane is recessed radially into the thrust reverser cascade from the cascade inner face.

Abstract: An apparatus is provided for an aircraft propulsion system. This apparatus includes a thrust reverser cascade extending longitudinally between a cascade forward end and a cascade aft end. The thrust reverser cascade extends laterally between a cascade first side and a cascade second side. The thrust reverser cascade extends radially between a cascade inner face and a cascade outer face. The thrust reverser cascade includes a plurality of vanes and a wall. The vanes are arranged in a longitudinally extending array along the cascade inner face. The vanes include a first vane and a second vane. The wall is configured to block gas flow radially through the thrust reverser cascade between the first vane and the second vane.

Abstract: An apparatus is provided for an aircraft propulsion system. This apparatus includes a thrust reverser cascade extending longitudinally between a cascade forward end and a cascade aft end. The thrust reverser cascade extends laterally between a cascade first side and a cascade second side. The thrust reverser cascade extends radially between a cascade inner face and a cascade outer face. The thrust reverser cascade includes a plurality of vanes and a wall. The vanes are arranged in a longitudinally extending array along the cascade inner face. The vanes include a first vane and a second vane. The wall is configured to block gas flow radially through the thrust reverser cascade between the first vane and the second vane.

Abstract: An acoustic attenuation structure for a gas turbine engine includes a periodic structure having a first unit cell, the first unit cell having a first central body and a first axial tube disposed on the first central body and a second axial tube disposed on the first central body, opposite the first axial tube, each of the first axial tube and the second axial tube being in fluid communication with one another through the first central body.

Abstract: An acoustic attenuation structure includes a periodic structure having a first unit cell, the first unit cell having a first central body and a first axial tube disposed on the first central body and a second axial tube disposed on the first central body, opposite the first axial tube, each of the first axial tube and the second axial tube being in fluid communication with one another through the first central body.

Abstract: A noise attenuation panel for a structure within a propulsion system includes a first plurality of unit cells; and a second plurality of unit cells, the second plurality of unit cells merged within the first plurality of unit cells, the first plurality of unit cells including a first periodic structure having a first unit cell, a second unit cell, a third unit cell and a fourth unit cell, each of the first unit cell, the second unit cell, the third unit cell and the fourth unit cell including a central body interconnected via a plurality of lateral tubes extending from the central body, the first periodic structure forming a first lateral layer of unit cells.

Abstract: An additively manufactured noise attenuation panel for a structure within an aircraft structure includes a plurality of unit cells, each including a central body interconnected via a plurality of tubes extending from the central body. The noise attenuation panel may include an increasing wall thickness in a desired direction. A layers of unit cells may be manufactured in a twisted orientation with respect to an immediately adjacent layer of unit cells. Layers of unit cells may be manufactured in a rounded or bent orientation with respect to a central axis. The noise attenuation panel may further comprise a disk and a blended transition located at the interface between the disk and an interior surface of a unit cell.

Abstract: A noise and vibration attenuation panel for a structure within a propulsion system includes a first plurality of unit cells and a first plurality of mass elements disposed within the first plurality of unit cells. The first plurality of unit cells include a first periodic structure having a first unit cell, a second unit cell, a third unit cell, and a fourth unit cell, each of the first unit cell, the second unit cell, the third unit cell and the fourth unit cell including a central body interconnected via a plurality of lateral tubes extending from the central body, the first periodic structure forming a first lateral layer of unit cells. The noise attenuation panel can simultaneously control acoustic waves or energy (i.e., via noise attenuation flow paths) and vibration (i.e., via the mass elements).

Abstract: An engine assembly includes a combustor wall with a first skin, a second skin, a core and a sound attenuation passage. The first skin forms a peripheral boundary of a combustion volume on a first side of the combustor wall. The second skin forms a peripheral boundary of a plenum on a second side of the combustor wall. The core includes a plurality of resonator elements between the first skin and the second skin. A first resonator element includes a first base and a plurality of first protrusions projecting out from the first base. Each first protrusion includes a first bore fluidly coupled with a first cavity within the first base. The sound attenuation passage extends within the core and is fluidly coupled with the combustion volume through an attenuation passage aperture in the first skin. The sound attenuation passage is fluidly decoupled from the plenum by the second skin.

Abstract: An engine assembly includes a combustor wall with a first skin, a second skin, a core and a sound attenuation passage. The first skin forms a peripheral boundary of a combustion volume on a first side of the combustor wall. The second skin forms a peripheral boundary of a plenum on a second side of the combustor wall. The core includes a plurality of resonator elements between the first skin and the second skin. A first resonator element includes a first base and a plurality of first protrusions projecting out from the first base. Each first protrusion includes a first bore fluidly coupled with a first cavity within the first base. The sound attenuation passage extends within the core and is fluidly coupled with the combustion volume through an attenuation passage aperture in the first skin. The sound attenuation passage is fluidly decoupled from the plenum by the second skin.

Abstract: A noise attenuation panel for a structure within a propulsion system includes a first plurality of unit cells; and a second plurality of unit cells, the second plurality of unit cells merged within the first plurality of unit cells, the first plurality of unit cells including a first periodic structure having a first unit cell, a second unit cell, a third unit cell and a fourth unit cell, each of the first unit cell, the second unit cell, the third unit cell and the fourth unit cell including a central body interconnected via a plurality of lateral tubes extending from the central body, the first periodic structure forming a first lateral layer of unit cells.

Abstract: An acoustic attenuation structure for a gas turbine engine includes a periodic structure having a first unit cell, the first unit cell having a first central body and a first axial tube disposed on the first central body and a second axial tube disposed on the first central body, opposite the first axial tube, each of the first axial tube and the second axial tube being in fluid communication with one another through the first central body.

Abstract: An acoustic attenuation structure includes a periodic structure having a first unit cell, the first unit cell having a first central body and a first axial tube disposed on the first central body and a second axial tube disposed on the first central body, opposite the first axial tube, each of the first axial tube and the second axial tube being in fluid communication with one another through the first central body.

Abstract: An acoustic supercell may comprise a facesheet having a plurality of perforations, a backplate parallel to the facesheet, a cell wall contacting the facesheet and the back plate, and a periodic structure. The supercell may be custom-tailored to meet specific acoustic wavelength absorption targets. The custom-tailored supercell may be arranged with a plurality of other custom-tailored supercells into an acoustic panel.

Abstract: An acoustic attenuation structure for a gas turbine engine includes a periodic structure having a first unit cell, the first unit cell having a first central body and a first axial tube disposed on the first central body and a second axial tube disposed on the first central body, opposite the first axial tube, each of the first axial tube and the second axial tube being in fluid communication with one another through the first central body.

Abstract: A system and method to moderate an airflow in a heating, ventilation, and air conditioning (HVAC) unit, including an evaporator portion disposed in a housing, the evaporator portion including at least one blower disposed within a plenum in airflow communication with a first heat exchanger, the plenum including at least one plenum wall, a vortex control device operably coupled to the at least one plenum wall.