Ram air system and methods of manufacturing the same

Patent metadata

Field	Value
Publication number	US-2016288912-A1
Application number	US-201514675807-A
Country	US
Kind code	A1
Filing date	Apr 1, 2015
Priority date	Apr 1, 2015
Publication date	Oct 6, 2016
Grant date	—

Abstract

A ram air system includes a bay comprising an exterior wall defining an interior volume that at least partially encloses a ram air duct. The ram air duct includes an outlet configured to discharge an exhaust airflow at a first temperature. At least one of the exterior wall and the ram air duct defines an aperture therein providing for flow communication between the bay interior volume and the exhaust airflow such that cooling air flows from the interior volume to form a boundary layer between the exhaust airflow and the exterior wall downstream of the outlet. The boundary layer is at a second temperature that is lower than the first temperature.

First claim

What is claimed is:

1 . A ram air system for use with a bay comprising an exterior wall defining an interior volume, the ram air system comprising:
a ram air duct at least partially enclosed within the interior volume, the ram air duct comprising an outlet configured to discharge an exhaust airflow at a first temperature; and an aperture defined in at least one of said exterior wall and said ram air duct, the aperture configured to provide flow communication directly between the bay interior volume and the exhaust airflow such that cooling air flows from the interior volume to form a boundary layer between the exhaust airflow and said exterior wall downstream of said outlet, the boundary layer being at a second temperature that is lower than the first temperature.

2 . The ram air system in accordance with claim 1 , wherein said aperture is defined in said ram air duct proximate said outlet.

3 . The ram air system in accordance with claim 1 , wherein a pressure of the exhaust airflow is lower than a pressure of the cooling air such that the cooling air is pulled through said aperture to form the boundary layer.

4 . The ram air system in accordance with claim 1 , wherein said aperture is defined at a lowest pressure region of said ram air duct.

5 . The ram air system in accordance with claim 1 , wherein said exterior wall comprises at least one opening defined therein providing for flow communication between the interior volume of said bay and a free stream airflow.

6 . The ram air system in accordance with claim 5 , wherein said opening is defined in said exterior wall upstream of said ram air duct outlet.

7 - 9 . (canceled)

10 . A method of manufacturing a ram air system for use in a bay having an interior volume at least partially defined by an exterior wall of the bay, said method comprising:
at least partially enclosing a ram air duct within the interior volume; defining an outlet of the ram air duct in the exterior wall, the outlet configured to discharge an exhaust airflow at a first temperature; and defining an aperture in at least one of the exterior wall and the ram air duct to provide for flow communication directly between the bay interior volume and the exhaust airflow such that cooling air flows from the interior volume to form a boundary layer between the exhaust airflow and the exterior wall downstream of the outlet, the boundary layer being at a second temperature that is lower than the first temperature.

11 . The method in accordance with claim 10 , wherein defining an aperture in at least one of the exterior wall and the ram air duct comprises defining an aperture in the ram air duct proximate the outlet.

12 . The method in accordance with claim 10 , wherein defining an aperture in at least one of the exterior wall and the ram air duct comprises defining an aperture at a lowest pressure region of the ram air duct.

13 . The method in accordance with claim 10 further comprising defining an opening in the exterior wall upstream of the outlet to provide for flow communication between the interior volume of said bay and a free stream airflow.

14 . The method in accordance with claim 10 further comprising coupling a door to the exterior wall proximate the aperture.

15 . The method in accordance with claim 14 further comprising coupling a control system in communication with the door, the control system configured to selectively position the door to control an amount of cooling air through the aperture.

16 . (canceled)

17 . An aircraft comprising:
a lower lobe portion comprising a bay comprising an exterior wall that defines an interior volume; a ram air system at least partially positioned in said lower lobe, said ram air system comprising a ram air duct at least partially enclosed within the interior volume, said ram air duct comprising an outlet defined in said exterior wall configured to discharge an exhaust airflow at a first temperature; and wherein at least one of said exterior wall and said ram air duct defines an aperture therein providing for flow communication directly between the bay interior volume and the exhaust airflow such that cooling air flows from the interior volume to form a boundary layer between the exhaust airflow and the exterior wall downstream of said outlet, the boundary layer being at a second temperature that is lower than the first temperature.

18 . The aircraft in accordance with claim 17 , wherein said aperture is defined in said ram air duct proximate said outlet.

19 . The aircraft in accordance with claim 17 , wherein said exterior wall comprises at least one opening defined upstream of said ram air duct outlet, said opening providing for flow communication between the interior volume of said bay and a free stream airflow.

20 . The aircraft in accordance with claim 17 further comprising:
a door coupled to said exterior wall proximate said aperture;
a control system configured to selectively position said door to control an amount of cooling air through said aperture; and
at least one sensor communicatively coupled to said control system, wherein a position of said door is controlled based on a signal from said at least one sensor.

21 . The ram air system in accordance with claim 1 , wherein said ram air duct comprises an inlet opposite said outlet, wherein said ram air duct is continuous between said inlet and said outlet.

22 . The ram air system in accordance with claim 1 , wherein said ram air duct comprises an inlet opposite said outlet, wherein said inlet is coplanar with said outlet.

23 . The aircraft in accordance with claim 17 further comprising:
a heat source positioned within said ram air duct, wherein said heat source is exposed to a cooling inlet flow within said ram air duct.

24 . The aircraft in accordance with claim 17 , wherein said lower lobe comprises a wing-to-body fairing of said aircraft.

Assignees

• Boeing Co

Inventors

• Richardson Marcus K
• Tonks Michael James
• Hart Colin W

Classifications

• B64D13/006 Primary

  the air being used to cool structural parts of the aircraft · CPC title

• B64D2013/0618

  with arrangements for reducing or managing bleed air, using another air source, e.g. ram air · CPC title

• B64D13/08

  the air being heated or cooled · CPC title

• B64D2013/0625

  comprising means for distribution effusion of conditioned air in the cabin · CPC title

• B64D13/00

  Arrangements or adaptations of air-treatment apparatus for aircraft crew or passengers, or freight space · CPC title