Outlet header of heat exchanger

1. A heat exchanger, which is a dual air heat exchanger for an aircraft, comprising:

a front side and a top side,

the front side facing a first direction and being a ram air inlet for receiving ram air flowing in the first direction,

the top side being an outlet of a primary heat exchanger disposed within the heat exchanger, wherein the top side faces a second direction that is perpendicular to the first direction,

an outlet header disposed against the top side of the heat exchanger and covering a portion of the top side of the heat exchanger, the outlet header receiving air from the outlet of the primary heat exchanger,

the outlet header including:

a unitary body including a front side disposed proximate the front side of the heat exchanger, an opposing rear side disposed distal the front side of the heat exchanger, a first side wall and an opposing second side wall, wherein a bottom of the unitary body is rectangular and forms an exterior boarder of a first opening for the outlet header, the first opening facing the outlet of the primary heat exchanger, wherein a first corner of the outlet header that is proximate the front side of the heat exchanger is disposed at a cold-cold corner of the heat exchanger, and wherein the exterior boarder of the outlet header is at least partially flanged for connecting with the top side of the heat exchanger, and

the unitary body having three openings, wherein the three openings are mutually perpendicular and progressively smaller, including the first opening, a second opening that is smaller than the first opening, and a third opening that is smaller than the second opening, wherein the second opening and the third opening are circular,

the second opening being an orifice of a primary conduit extending in the first direction from the rear wall of the unitary body, wherein the first opening directs cooled air from the primary hot circuit within the heat exchanger through the second opening, and

the third opening being an orifice of a first leg of an L-tube extending into the first side wall of the unitary body proximate the cold-cold corner of the heat exchanger, wherein a second leg of the L-tube extends downwardly toward the bottom of the unitary body to capture cool air from the cold-cold corner and to direct the cool air to out of the primary heat exchanger through a flow-tap-off duct fluidly connected to the first leg of the L-tube.

2. The heat exchanger of claim 1 , wherein the cold-cold corner is defined by a volume of an interior of the heat exchanger that is located most closely to a cool-air source upon entrance of corresponding cool air into the heat exchanger and opposite a source of hot-air flow upon entrance of bleed air into the heat exchanger.

3. The heat exchanger of claim 1 , wherein the first leg is matingly received in the flow-tap-off duct such that a first end of the first leg sits slightly inboard of a free end of the flow-tap-off duct and a second end of the first leg extends at least slightly into an interior of the outlet header.

4. The heat exchanger of claim 3 , wherein the second leg is positioned within the interior of the outlet header and spaced from an interior side of the outlet header.

5. The heat exchanger of claim 1 , wherein the first leg defines a pair of opposed holes receives a fastener for mechanically installing the L-tube to the flow-tap-off duct and, thus, outlet header.

6. The heat exchanger of claim 5 , wherein the fastener is a rivet disposed in each of the holes.

7. The heat exchanger of claim 5 , wherein the fastener is a combination of a bolt, nut, and curved washer.

8. The heat exchanger of claim 5 , wherein the L-tube is retrofitted to an existing flow-tap-off duct.

9. The heat exchanger of claim 1 , wherein epoxy fills any gaps between the first leg and flow-tap-off duct in the installation and acts as a secondary form of retention between the first leg and flow-tap-off duct.