Heat exchanger

Abstract

A heat exchanger includes a conduit, a header, and a swirler been formed as a unitary piece by additive manufacturing. The swirler is disposed within the conduit and the header and is arranged to disperse a flow from an inlet flow path a heat exchanger matrix. The swirler extends a only portion of the length of the header between the conduit and the heat exchanger matrix and thereby provides space within the header for fluid to diffuse before entering the heat exchanger matrix.

Claims

1. A heat exchanger comprising: a conduit defining an inlet flow path for a fluid; a header disposed to receive a flow from the inlet flow path; a heat exchanger matrix disposed to receive a flow from the header; and a swirler disposed within the conduit and the header, wherein the swirler is arranged to disperse a flow from the inlet flow path over the heat exchanger matrix, and wherein the swirler extends over only a portion of the length of the header between the conduit and the heat exchanger matrix and thereby provides space within the header for fluid to diffuse before entering the heat exchanger matrix; wherein the conduit, header, and swirler have been formed as a unitary piece by additive manufacturing; and wherein the portion of the swirler in the header extends across the entire width of the heat exchanger matrix in two dimensions, and extends across the entire width of the header in two dimensions and joins integrally with opposing walls of the header, and is thereby arranged to provide structural support to the header during use and during formation of the header by additive manufacturing.

2. A heat exchanger as claimed in claim 1, wherein the swirler divides the header into a plurality of equal volumes.

3. A heat exchanger as claimed in claim 1, wherein the swirler comprises a plurality of curved blades arranged to direct a flow of fluid through the inlet flow path and the header.

4. A heat exchanger as claimed in claim 3, wherein the blades are smooth between the conduit and the header.

5. A heat exchanger as claimed in claim 3, wherein the swirler blades curve through 90 degrees along their entire length.

6. A heat exchanger as claimed in claim 1, wherein the swirler is arranged to complement the shape of a cross section of the heat exchanger matrix.

7. An aircraft comprising a heat exchanger as claimed in claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Certain example embodiments of the invention will be described in further detail below by way of example only and with reference to the accompanying drawings in which:

(2) FIG. 1 shows a heat exchanger;

(3) FIG. 2 shows a heat exchanger with a swirler;

(4) FIG. 3A shows a flow diagram of fluid with a heat exchanger with a swirler;

(5) FIG. 3B shows an alternative view of the flow diagram of FIG. 3A;

(6) FIG. 4 shows a schematic of the manufacture of a swirler using additive manufacturing;

(7) FIG. 5 shows a schematic of the manufacture of a header, swirler and conduit using additive manufacturing;

(8) FIG. 6A shows a transparent perspective view of the header, swirler, and conduit of FIG. 5; and

(9) FIG. 6B shows a perspective view of the header of FIG. 6A.

DETAILED DESCRIPTION

(10) FIG. 1 shows a heat exchanger 100 comprising a conduit 110, header 120 and heat exchanger matrix 150. Fluid 140 flows along the conduit 110 and into the header 120, where it disperses before entering the heat exchanger matrix 150. FIG. 2 shows a heat exchanger similar to that of FIG. 1. Fluid 140 flows along the conduit 110 at a higher speed than in the conduit 110 of FIG. 1. The fluid 140 then flows through a swirler 130 and is dispersed thereby into a volume defined by the header 120, before entering the heat exchanger matrix 150.

(11) FIG. 3A shows the speed of a fluid flow in the heat exchanger of FIG. 2. The fluid 140 flows along the conduit 110 at speeds of more than 300 m/s, up to speeds of 500 m/s, or even 1000 m/s. The fluid 140 reaches the swirler 130 and is directed thereby into the volume of the header 120, and subsequently into the heat exchanger matrix 150. The heat exchanger matrix 150 is arranged to carry a second fluid (not shown) so as to be in heat exchange with the first fluid 140.

(12) FIG. 3B shows an end-on view of the heat exchanger of FIG. 3A. The heat exchanger matrix 150 defines a plurality of channels which run horizontally, substantially perpendicular to the flow path of the fluid 140 so as to maximise contact therewith. Dispersal of the fluid 140 into the volume defined by the header 120 and heat exchanger matrix 150 is indicated by the flow lines.

(13) FIG. 4 shows a swirler 130 in various stages of production by an additive manufacturing process. The swirler 130 comprises four blades 132 and a sleeve portion 134 surrounding the blades. The swirler 130 is formed by the addition of incremental layers, defining the blades 132 and sleeve portion 134. The swirler 130 may be made to the desired dimensions simultaneously with a conduit of the heat exchanger.

(14) FIG. 5 shows the manufacture of the header 120, swirler 130 and conduit 110 of the heat exchanger 100 at different stages of the process. The blades 132 of the swirler 130 are formed integrally with the walls 124 of the header 120, thereby supporting the header during formation and preventing its collapse. The swirler 130 has a cross shaped cross section, which rotates relative to the header 120 as subsequent layers are added to the integral piece. Once the header 120 is formed, the process continues by the additive manufacture of the swirler 130 within the conduit 110.

(15) The unitary piece comprising the header 120, swirler 130 and conduit 110 are shown as being formed with the header 120 and header portion of the swirler 130 first, followed by the conduit 110 and conduit portion of the swirler 130. This order of formation allows the unitary piece to be stable during manufacture, but any suitable order of manufacture may be used. The heat exchanger matrix 150 is shown in transparency in FIG. 5, and may be formed together with the conduit 110, header 120, and swirler 130 during the same additive manufacturing process.

(16) As can be seen from FIG. 5, fluid flowing along the conduit 110 will encounter the swirler 130 and be directed by the blades 132 into the header, where it will continue to be directed by the blades 132 while dispersing, until it encounters the heat exchanger matrix 150.

(17) FIG. 6A shows a transparent view of the conduit 110 and header 120 in which the continuous curve of the blades 132 of the swirler 130 can be seen. The conduit and header 120 form an envelope about the swirler 130, which is thus formed integrally with the header 120 and the conduit 110 and is connected thereto at the edges of the blades 132. The header 120 is of course also formed integrally with the conduit 110.

(18) The blades 132 of the swirler 130 extend the entire length of the header 120, and support all the header walls 124 at each of the surfaces of the header 120. FIG. 6B shows a perspective of the unitary header 120, swirler 130 and conduit 110 from below. A portion of the inlet 111 of the conduit 110, which defines an inlet flow path, can be seen. It can be seen in FIG. 6 that the blades 132 continue smoothly and uninterruptedly from the conduit 110 into the space within the header 120, thereby ensuring an efficient flow of fluid from the conduit.

(19) The method and apparatus described herein and shown in the drawings provides a means of manufacturing at least a part of a heat exchanger in an efficient and simple manner using additive manufacturing. Because additive manufacturing is used, the resulting heat exchanger may be formed using only the necessary amount of material, thereby ensuring optimum weight and structural integrity of the component. While the apparatus and method herein have been shown and described with reference to exemplary embodiments, those skilled in the art will appreciate that changes and/or modifications may be made thereto without departing from the scope of the present invention as defined by the appended claims.