초록 ▼

An aircraft includes at least one turbofan engine assembly having a shrouded core engine, a short nacelle surrounding a fan and a forward portion of the core engine, and a fan exhaust duct through the nacelle. A mixer duct shell is positioned substantially coaxial with the engine shroud and extends

An aircraft includes at least one turbofan engine assembly having a shrouded core engine, a short nacelle surrounding a fan and a forward portion of the core engine, and a fan exhaust duct through the nacelle. A mixer duct shell is positioned substantially coaxial with the engine shroud and extends forwardly into the fan duct to provide an interstitial mixer duct between the mixer duct shell and the core engine shroud. The aft portion of the mixer duct shell extends over a turbine exhaust frame, an attached mixer (if included), and a tail cone exhaust plug. The mixer duct shell can reduce noise and plume exhaust heat radiated from aircraft turbofan engines.

대표청구항 ▼

What is claimed is: 1. An aircraft comprising: at least one turbofan engine assembly having a fan driven by a core engine, a short nacelle around the fan and a forward portion of the core engine, and a fan exhaust duct through the nacelle; a mixer duct shell substantially coaxial with and extending

What is claimed is: 1. An aircraft comprising: at least one turbofan engine assembly having a fan driven by a core engine, a short nacelle around the fan and a forward portion of the core engine, and a fan exhaust duct through the nacelle; a mixer duct shell substantially coaxial with and extending forwardly into the fan exhaust duct to provide a mixer duct between the mixer duct shell and the core engine; and a plurality of pillar mounts by which the mixer duct shell is mounted around the core engine, the pillar mounts positioned downstream of an outer wall exit plane of the fan exhaust duct and aligned to coincide with crowns of a plurality of lobes of a flow mixer on an aft section of the core engine within the mixer duct shell; the mixer duct shell comprising a leading edge rearward of a thrust reversal device of the at least one engine assembly, the shell leading edge configured with the thrust reversal device to provide, when the thrust reversal device is deployed, a gap between the leading edge and the thrust reversal device through which a flow of air from the fan exhaust duct is reversed into the mixer duct. 2. The aircraft of claim 1, the mixer duct shell comprising a fixed forward portion, a movable aft portion, the pillar mounts selectively operable to engage the mixer duct shell aft portion with the mixer duct shell forward portion and to release the mixer duct shell aft portion for separation from the mixer duct shell forward portion; each pillar mount having a forward part affixed to the mixer duct shell forward portion and to a shroud of the core engine, and an aft part affixed to the mixer duct shell aft portion and engagable with the pillar mount forward part. 3. The aircraft of claim 1, the mixer duct shell comprising an aft portion slidable selectively into and out of engagement with a forward portion of the mixer duct shell while supported in a track on a nylon to which the engine is mounted. 4. The aircraft of claim 1, the mixer duct shell comprising a nozzle exit edge having a plurality of chevrons. 5. The aircraft of claim 1, wherein the fan and mixer ducts are configured to provide partial mixing of fan and engine exhausts. 6. The aircraft of claim 1, the mixer duct shell further comprising one or more acoustic liners lining at least part of at least one surface of the shell. 7. The aircraft of claim 1, the mixer duct shell further comprising one or more debris containment liners lining at least part of an inner surface of the shell. 8. The aircraft of claim 1, wherein a portion of the short nacelle and a portion of a shroud of the core engine are configured to be raised with a portion of the mixer duct shell to provide access to the core engine. 9. The aircraft of claim 1, each pillar mount having a forward part affixed to the mixer duct shell forward portion and to a shroud of the core engine, and an aft part affixed to the mixer duct shell aft portion; the pillar aft parts detachable from the pillar forward parts to springably release the mixer duct shell aft portion from the mixer duct shell forward portion. 10. An aircraft comprising: at least one turbofan engine assembly having a core engine, a short nacelle around a forward portion of the core engine, and a fan duct through the nacelle; and a mixer duct shell mounted around an aft portion of the core engine and having a forward portion extending forwardly into an exit nozzle of the nacelle to provide a mixer duct between the mixer duct shell and the core engine aft portion, the forward portion of the mixer duct shell being fixedly attached to a shroud of the core engine, an aft portion of the mixer duct shell being supported in a track on a pylon to which the engine is mounted, the aft portion of the mixer duct shell slidable along the track in an aft-ward direction to expose part of the shroud; the mixer duct shell comprising a leading edge rearward of a thrust reversal device of the at least one engine assembly, the shell leading edge configured with the thrust reversal device to provide, when the thrust reversal device is deployed, a gap between the leading edge and the thrust reversal device through which a flow of air from the fan exit nozzle is reversed into the mixer duct. 11. The aircraft of claim 10 wherein the mixing of fan exhaust with engine exhaust is at about a 2:1 mass flow ratio. 12. The aircraft of claim 10, the mixer duct shell further comprising an exit nozzle edge having a plurality of chevrons. 13. The aircraft of claim 10, the mixer duct shell further comprising one or more acoustic liners lining at least part of at least one surface of the shell. 14. The aircraft of claim 10, the mixer duct shell further comprising one or more debris containment liners lining at least part of an inner surface of the shell. 15. The aircraft of claim 10, wherein a portion of the short nacelle and a portion of a shroud of the core engine are configured to be raised with a portion of the mixer duct shell to provide access to the core engine. 16. The aircraft of claim 10, the mixer duct shell comprising a plurality of pillar mounts by which the mixer duct shell aft portion is reversibly engaged with the mixer duct shell forward portion; each pillar mount having a forward part affixed to the mixer duct shell forward portion and to the shroud, and an aft part affixed to the mixer duct shell aft portion; the pillar aft parts detachable from the pillar forward parts to springably release the mixer duct shell aft portion from the mixer duct shell forward portion. 17. An aircraft comprising: at least one turbofan engine assembly having a fan driven by a core engine, a short nacelle around the fan and a forward portion of the core engine, and a fan exhaust duct through the nacelle; a mixer duct shell substantially coaxial with and extending forwardly into the fan exhaust duct to provide a mixer duct between the mixer duct shell and the core engine; the mixer duct shell comprising a leading edge rearward of a thrust reversal device of the at least one engine assembly, the shell leading edge configured with the thrust reversal device to provide, when the thrust reversal device is deployed, a gap between the leading edge and the thrust reversal device through which a flow of air from the fan exhaust duct is reversed into the mixer duct; the mixer duct shell having a fixed forward portion, a movable aft portion, and a plurality of pillar mounts selectively operable to engage the mixer duct shell aft portion with the mixer duct shell forward portion and to release the mixer duct shell aft portion for separation from the mixer duct shell forward portion; each pillar mount having a forward part affixed to the mixer duct shell forward portion and to a shroud of the core engine, and an aft part affixed to the mixer duct shell aft portion and engagable with the pillar mount forward part. 18. The aircraft of claim 17, the pillar mounts aligned to coincide with crowns of a plurality of lobes of a flow mixer on an aft section of the core engine within the mixer duct shell. 19. The aircraft of claim 17, the aft portion of the mixer duct shell slidable selectively into and out of engagement with the forward portion of the mixer duct shell while supported in a track on a pylori to which the engine is mounted. 20. The aircraft of claim 17, the mixer duct shell comprising a nozzle exit edge having a plurality of chevrons. 21. The aircraft of claim 17, wherein the fan and mixer ducts are configured to provide partial mixing of fan and engine exhausts. 22. The aircraft of claim 17, the mixer duct shell further comprising one or more acoustic liners lining at least part of at least one surface of the shell. 23. The aircraft of claim 17, the mixer duct shell further comprising one or more debris containment liners lining at least part of an inner surface of the shell. 24. The aircraft of claim 17, wherein a portion of the short nacelle and a portion of a shroud of the core engine are configured to be raised with a portion of the mixer duct shell to provide access to the core engine. 25. The aircraft of claim 17, the pillar aft parts detachable from the pillar forward parts to springably release the mixer duct shell aft portion from the mixer duct shell forward portion.