Internal mixing of a portion of fan exhaust flow and full core exhaust flow in aircraft turbofan engines
AssigneeThe Boeing Company
InventorsMatthew D. Moore, Edward C. Marques
Life of this patent
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Abstract
A method of controlling plume exhaust heat and/or noise radiation from a turbofan engine assembly having a short nacelle. A mixer duct shell is supported such that a downstream edge of the short nacelle overlays an upstream portion of the mixer duct shell. A first portion of fan exhaust may be routed through the mixer duct shell between its inner surface and an outer surface of a core engine shroud. A second portion of fan exhaust may be routed over an outer surface of the mixer duct shell. At least one of the inner surface and an outer surface of the mixer duct shell may have an acoustic lining including a honeycomb core structure.
Claims20
A method of controlling plume exhaust heat and/or noise radiation from a turbofan engine assembly having a short nacelle, the turbofan engine assembly providing a fan exhaust and being mounted on an airborne mobile platform, the method comprising:
- providing a mixer duct shell supported such that a downstream edge of the short nacelle overlays an upstream portion of the mixer duct shell;
- routing a first portion of the fan exhaust through the mixer duct shell between an inner surface of the mixer duct shell and an outer surface of a core engine shroud, wherein the core engine shroud is covering a core engine, the first portion of the fan exhaust being directed towards a nozzle of the mixer duct shell;
- routing a portion of exhaust gases of the core engine from a lobed mixer to adjacent the inner surface of the mixer duct shell to mix the portion of the exhaust gases of the core engine with the first portion of the fan exhaust to form a mixed exhaust, the mixed exhaust exiting the nozzle of the mixer duct shell;
- routing a second portion of the fan exhaust over an outer surface of the mixer duct shell;
- routing an engine case ventilation flow adjacent the core engine and an inward surface of the core engine shroud and subsequently inside the lobed mixer;
- and
- covering at least one of the inner surface of the mixer duct shell and the outer surface of the mixer duct shell with an acoustic lining including a honeycomb core structure.
A method of controlling plume exhaust heat and/or noise radiation from a turbofan engine assembly having a short nacelle, the turbofan engine assembly providing a fan exhaust and being mounted on an airborne mobile platform, the method comprising:
- providing a mixer duct shell supported such that a downstream edge of the short nacelle overlays an upstream portion of the mixer duct shell;
- routing a first portion of the fan exhaust through the mixer duct shell between an inner surface of the mixer duct shell and an outer surface of a core engine shroud, wherein the core engine shroud is covering a core engine, the first portion of the fan exhaust being directed towards a nozzle of the mixer duct shell;
- routing a portion of exhaust gases of the core engine from a lobed mixer to adjacent the inner surface of the mixer duct shell to mix the portion of the exhaust gases of the core engine with the first portion of the fan exhaust to form a mixed exhaust, the mixed exhaust exiting the nozzle of the mixer duct shell;
- routing a second portion of the fan exhaust over an outer surface of the mixer duct shell;
- routing an engine case ventilation flow adjacent the core engine and an inward surface of the core engine shroud and subsequently inside the lobed mixer;
- and
- covering at least one of the inner surface of the mixer duct shell and the outer surface of the mixer duct shell with an acoustic lining, the acoustic lining including a plurality of distinct layers of material.
A method of controlling plume exhaust heat and/or noise radiation from a turbofan engine assembly having a short nacelle, the turbofan engine assembly providing a fan exhaust and being mounted on an airborne mobile platform, the method comprising:
- providing a mixer duct shell supported such that a downstream edge of the short nacelle overlays an upstream portion of the mixer duct shell;
- routing a first portion of the fan exhaust through the mixer duct shell between an inner surface of the mixer duct shell and an outer surface of a core engine shroud, wherein the core engine shroud is covering a core engine, the first portion of the fan exhaust being directed towards a nozzle of the mixer duct shell;
- routing a portion of exhaust gases of the core engine from a lobed mixer to adjacent the inner surface of the mixer duct shell to mix the portion of the exhaust gases of the core engine with the first portion of the fan exhaust to form a mixed exhaust, the mixed exhaust exiting the nozzle of the mixer duct shell;
- routing a second portion of the fan exhaust over an outer surface of the mixer duct shell;
- routing an engine case ventilation flow adjacent the core engine and an inward surface of the core engine shroud and subsequently inside the lobed mixer;
- and
- covering at least one of the inner surface of the mixer duct shell and the outer surface of the mixer duct shell with an acoustic lining.
Dependencies are inferred from the claim text.