Patent ID: 12188412

DETAILED DESCRIPTION

The figures and the non-limiting detailed descriptions thereof disclose the invention according to particular methods which are not limiting regarding the scope of the invention as claimed. The figures and their detailed descriptions of an exemplary embodiment of the invention may serve to define said exemplary embodiment in an optimized manner, if required in relation to the general description which has been made above. Moreover, to avoid overloading the figures and to facilitate the reading thereof, the reference numerals assigned to the terms and/or concepts used to describe the invention and indicated on any one of the figures are potentially repeated in the description of any other figure without implying the presence thereof in all of the figures.

InFIG.1, a heat exchanger1for cooling an aircraft propulsion engine has an annular configuration having the axis A1. The exchanger1is provided for any type of motorized aircraft, such as airplanes, helicopters, rockets, missiles, etc.

The heat exchanger1comprises a plurality of heat exchanger modules2which are mutually independent, being distributed circumferentially about the axis A1of the ring. The modules2are assembled with one another, being successively spaced apart in pairs, with the resulting formation of spaces E1created between two adjacent modules2. The spacing-apart permits the formation of a modular annular heat exchange assembly, the mechanical structure thereof being optimized. Such spaces E1are each traversed by the air flows F1agenerated by the advancing aircraft. Each space E1forms a circulation channel for the air flow F1agenerated by the advancing aircraft.

Each module2comprises first channels3afor the circulation of the air flow F1bgenerated by the advancing aircraft. The air flows F1bpassing through the modules2are utilized for cooling a cooling fluid which circulates through the second channels3bwhich each of the modules comprise, and are utilized at the outlet of the heat exchanger1to cool a propulsion engine of the aircraft. It is understood by reading the figures that the first channels3aand the second channels3bare illustrated in broken lines and partially referenced in number.

The first channels3alocated inside the modules2and the channels formed by the spaces E1extend in the same direction (i.e. in the direction of the air flow F1a). All of the channels3a,2are parallel and distributed over the circumference of the heat exchanger1.

The second channels3balso extend in the same direction F1aas the first channels3aand the channels formed by the spaces E1.

The internal design of the exchanger is thus both simplified and optimized, all of the channels which circulate the flow F1aof air (first channels3aand channels formed by the spaces E1), in addition to all of the channels which circulate the fluid to be cooled (second channels3b), extend in the same direction, sharing the heat exchange walls therebetween.

More particularly visible inFIGS.2and3, it will be noted that the modules2are provided at each of their radial ends with said one second channel3bwhich is delimited by at least one radial end wall4of the modules2which is oriented toward the separating spaces E1between two adjacent modules2. In other words, the adjacent radial end walls4of the modules2are walls4of the modules2which are oriented facing one another, said one space E1being formed therebetween.

The ring forming the heat exchanger1has more specifically a generally conical shape, being axially tapered A1from an axial end5aupstream of the ring toward an axial end5bdownstream of the ring, the terms “upstream” and “downstream” being defined according to the direction of circulation of the air flows F1a, F1bthrough the heat exchanger1. The ring forming the heat exchanger1has an external face6aidentified by at least one larger external diameter D1a, D1bof the ring and an internal face6bidentified by at least one smaller internal diameter D1a, D2bof the ring.

More particularly visible inFIG.3, a first generatrix defining the surface of revolution of the external face6aof the ring and a second generatrix defining the surface of revolution of the internal face6bof the ring are differentiated, which provides the ring along the axis A1with a double curvature, respectively on its external face6aand its internal face6b.

Said spaces E1each receive conductive heat-transfer elements7which extend between the respective opposing walls4of two adjacent modules2. The heat-transfer elements7are subjected to the air flow F1atraversing the spaces E1during the advance of the aircraft for the cooling thereof. The heat-transfer elements7thus cooled transfer their heat by conduction to said opposing walls4, to contribute to the cooling of the cooling fluid via said opposing walls4.

More particularly visible inFIGS.2and3, the heat-transfer elements7are formed from a plurality of fins8which are integrated in the opposing walls4of two adjacent modules2, respectively in sets of fins8. Each fin8protrudes substantially perpendicularly from the wall4, being made in one piece with the wall4.

The fins8each extend principally along an overall plane which is oriented between the walls4facing one another. Each space E1is delimited by two radial end walls4of two modules2, and each of these walls4also delimits one of the second channels3b. In each space E1, each heat-transfer element7is produced by two protruding fins8arranged in the extension of one another, one of these fins8protruding from one of the walls4delimiting the space E1and the other of these fins protruding from the other wall4. In other words, the fins8are arranged in pairs of fins8which each protrude from one of the walls4facing one another.

Moreover, for each pair of fins8facing one another, the ends of these fins8are not in contact, a small separating distance being provided between the two ends of these opposing fins8(seeFIG.3). This assembly makes it possible to ensure a heat exchange in the spaces E1which is as efficient as in the first channels3a, whilst maintaining the possibility of disassembling the exchanger1by disassembling the modules2, without any intervention relative to the heat-transfer elements7. The mutual assembly and disassembly of the modules3assembles or disassembles the heat-transfer elements7produced by the fins8jointly with the modules2in a simple and rapid manner.

Moreover, for each pair of opposing fins8in the space E1, the separating distance provided between the two ends of fins8allows for the deformations caused by changes in temperature without having any consequences for the mechanical structure of the assembly. These separating distances also make it possible to create modular exchangers in which, for example, a module2may be added to an existing exchanger1by being interposed between two further modules2. The exchanger1will thus be modified by adding a module1and thus will increase in diameter which will change the angles formed at the junction between each pair of modules2, without having any consequences for the heat exchange in the region of the spaces E1, due to the presence of these separating distances between each pair of opposing fins8.

More particularly visible inFIG.3, the generatrices defining the surfaces of revolution respectively of the external face6aand of the internal face6bof the ring are differentiated as referred to above. The ring thus has along its edge T1a variation in thickness Ep1, Ep2between its axial ends5a,5b. The fins8are distributed between the modules2according to a plurality of said guidelines which are parallel to one another and which extend in particular according to one of said generatrices, such as for example according to the second generatrix defining the surface of revolution of the internal face6bof the ring.

As a result, the number of fins8created inside each of the spaces E1varies along the axis A1according to the variation in thickness Ep1, Ep2of the edge T1of the ring. More specifically, considering the number of fins8created at the respective axial ends5a,5bof the ring, the number of fins8reduces from the axial end5aupstream of the ring to its downstream axial end5b. Further variants, not shown, may be implemented for distributing the fins8inside the spaces E1, in particular according to the drainage conditions of the air flows F1atraversing the spaces E1, making it possible to control the flow thereof and thus reduce the drag of the aircraft in an optimized manner.

More particularly visible inFIGS.2and3, the spaces E1are closed on the external face6aof the ring and on the internal face6bof the ring, in order to channel the air flows F1awhich traverse the spaces E1and in order to force the passage thereof between the fins8for the cooling thereof. To this end, covers9a,9bare placed respectively on the external face6aof the ring for an external cover9aand on the internal face6bof the ring for an internal cover9b.

According to the illustrated example, each of the covers9a,9bis composed of two cover elements10a,10bwhich are respectively integral with opposing walls4of two adjacent modules2. The adjacent edges along the axial extension A1of the cover elements10a,10bconsisting of one and the same cover9a,9bare sealed relative to one another to prevent an escape therebetween of the air from the air flow F1aflowing through the spaces E1.

The cover elements10a,10bwhich are integral with one and the same wall4constituting a module2are connected integrally to one another by being created at the respective ends of an adjoining wall11a,11bextending between the external face6aand the internal face6bof the ring. In other words, a covering element of one and the same space E1is formed from a one-piece assembly arranged in a section which has a U-shaped profile. The covering element comprises an external cover element10aor10band an internal cover element10a,10bconnected together by an adjoining wall11a,11b. Two covering elements cooperating together are respectively applied against the opposing walls4of two adjacent modules2.

It will be noted that the spaces E1separating two adjacent modules are thus each occupied by an additional thermal transfer heat exchanger which is interposed between two adjacent modules. The additional thermal transfer heat exchanger comprises a housing formed by said covering elements adjacent to one another, said housing receiving the heat-transfer elements7, making it possible to cool the opposing walls4of the two adjacent modules.

Each of the modules2is advantageously produced by printing a metal material, in particular aluminum, in three dimensions. According to one embodiment, not shown, each of the modules2may be composed of a plurality of elementary modules which are individually produced by printing in three dimensions and which are in abutment against one another in fluidic communication along the axis A1. Such an abutment may be implemented by sealing and/or by successively nesting the elementary modules in pairs, possibly in a sealed manner, the first channels3aand the second channels3bof the elementary modules in abutment respectively being in fluidic communication with one another. This makes it possible to produce modules2by printing in three dimensions at low cost and/or to enable the heat exchanger1to be provided with a low-cost adaptation of its axial extension A1according to the cooling requirements to be supplied.