Aircraft provided with an engine and an exhaust duct around an exhaust nozzle of the engine
AssigneeAirbus Helicopters
InventorsGuillaume Legras, Philippe Pinto, Christophe Albertini
Life of this patent
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Abstract
An exhaust duct configured to be arranged around an exhaust nozzle of an engine, the exhaust duct having a plurality of sections. The sections are circular between an inlet section and an outlet section, with the exception of the sections of a deformed segment, each section of the deformed segment extending from a bottom sector to a top sector, the bottom sector having a non-circular shape so that at least a volume of liquid that is not able to reach, by force of gravity, the inlet section and the outlet section, is less than a volume threshold when the pitch and roll angles respectively lie within predetermined pitch and roll angle ranges.
Claims12
An exhaust duct configured to be arranged around an exhaust nozzle of an engine, the exhaust duct having a plurality of sections, the sections comprising an inlet section and an outlet section, the exhaust duct extending along a guiding line from the inlet section to the outlet section, the outlet section being configured to expel gases discharged by the exhaust nozzle,
- wherein the sections are circular between the inlet section and the outlet section, with the exception of the sections of a deformed segment, each section of the deformed segment comprising a bottom sector and a top sector, the bottom sector having a non-circular shape so that at least a volume of liquid that is not able to reach, by force of gravity, the inlet section and the outlet section, is less than a volume threshold when the pitch and roll angles respectively lie within predetermined pitch and roll angle ranges.
A method for designing the exhaust duct configured to be arranged around an exhaust nozzle of an engine, the exhaust duct having a plurality of sections, the sections comprising an inlet section and an outlet section, the exhaust duct extending along a guiding line from the inlet section to the outlet section, the outlet section being configured to expel gases discharged by the exhaust nozzle,
- wherein the design method comprises defining a hose with circular sections extending from the inlet section to the outlet section, the design method comprising at least one modification phase comprising the following steps:
- determining at least one undrainable volume delimited by the hose and wherein a liquid cannot, by force of gravity, reach the inlet section and the outlet section at pitch and roll angles that respectively lie within predetermined pitch and roll angle ranges;
- if no undrainable volume is greater than or equal to a volume threshold, assigning a geometry of the hose to the exhaust duct;
- and
- if at least one undrainable volume is greater than or equal to the volume threshold:
- (i) positioning a predetermined shape intersecting the hose, the undrainable volume (s) being present between the hose and the predetermined shape;
- (ii) modifying the hose, the part of the hose situated beneath the predetermined shape and comprising the undrainable volume (s) being cut off and replaced locally by the predetermined shape;
- and (iii) carrying out a new modification phase with the hose obtained after the modification of the hose.
Dependencies are inferred from the claim text.