Heat exchanger equipped with an interface box with guide fins

Abstract

The present invention relates to a heat exchange device for performing heat exchange between two heat transfer fluids, the heat exchange device comprising: an outer casing (10) delimiting a circulation chamber (12) for the heat transfer fluids; an inlet (20) and an outlet (30) for the flow of a first heat transfer fluid into the chamber; an inlet and an outlet for the flow of a second heat transfer fluid into the chamber; an exchanger block (14) arranged in the circulation chamber (12). The heat exchange device further comprises at least one interface box (20) forming one of the inlets or one of the outlets of the fluids, the interface box comprising a dome-shaped casing (24) provided with an inlet / outlet aperture (26) and an interface frame mechanically connected to the outer casing. The box (20) further comprises a plurality of separate guiding fins (22a, 22b, 22c, 22b) extending between the aperture and the interface frame.

Description

Technical Field

[0001] This invention relates to a heat exchanger equipped with a fluid flow collection tank and / or a fluid flow distribution tank, the fluid flow collection tank and / or fluid flow distribution tank including guide fins for fluid flow. The invention particularly relates to such an exchanger intended for aviation use. Background Technology

[0002] Heat exchangers, especially those designed to equip aircraft, are susceptible to significant temperature gradients during their operating cycle. This is particularly true for heat exchangers designed to cool high-pressure air drawn from the aircraft's propulsion engines (more commonly known as bleed air) or from the auxiliary power unit (usually abbreviated as APU).

[0003] When a heat exchanger is initially supplied with bleed air, the temperature of the internal components of the exchanger block (also known as the "core") rises faster than that of adjacent components and the periphery of the exchanger block. This creates a temperature gradient, which in turn generates mechanical stresses that can cause possible deformation of the exchanger components (e.g., rotation of the exchanger block's sealing rods). Such deformation can be severe enough to cause some components to rupture, manifesting as cracks or detachment of brazed parts. These phenomena create a risk of fluid leakage, either inside the exchanger or even towards the outside.

[0004] To enhance the mechanical strength of the heat exchanger and facilitate the supply and distribution of fluids (such as air) to the heat exchanger, it is common practice to equip such heat exchangers with fluid flow collection boxes and / or fluid flow distribution boxes, which are mechanically connected to the blocks of the exchanger.

[0005] Throughout the following content, fluid will be referred to primarily by the term "air," but it should be understood that another fluid, primarily a gaseous fluid, may be used within the scope of this invention.

[0006] The distribution box typically supplies air from a duct with a circular cross-section. The distribution box delivers the received air to an exchanger block, which is generally parallelepiped in shape and is formed, for example, by a stack of plates that form circulation channels in pairs, allowing airflow within the exchanger block in a thermally interactive manner. A flow collection box receives the air at the outlet of the exchanger block and delivers it to a duct with a generally circular cross-section.

[0007] These geometric changes (circular pipes facing parallelepiped exchanger blocks, and parallelepiped exchanger blocks facing circular pipes) generate vortices within the collection and distribution boxes that can affect airflow.

[0008] In other words, collection boxes and distribution boxes (hereinafter referred to as interface boxes) are necessary to ensure airflow between the pipes and the heat exchanger blocks, as well as to ensure mechanical resistance to pressure and stress on the heat exchanger, which is crucial given the constraints mentioned above.

[0009] Therefore, the inventors have sought to propose an evolution of heat exchangers, and in particular an evolution of the interface box, so that the collection and distribution of airflow in the exchanger are coordinated with the mechanical constraints of the exchanger. Summary of the Invention

[0010] Purpose of the invention The present invention aims to provide a heat exchange device that overcomes at least some of the defects of known devices.

[0011] The present invention also aims to provide, in at least one embodiment, a switching device that enables the limitation of pressure loss.

[0012] The present invention also aims to provide, in at least one embodiment, a switching device that can be obtained from known switching devices without significant structural modifications.

[0013] The present invention also aims to provide, in at least one embodiment, a device that can exhibit better thermomechanical performance than known exchange devices. Invention Overview Therefore, the present invention relates to a heat exchange device for heat exchange between two heat transfer fluids, the heat exchange device comprising: - The outer casing defines the circulation chamber for the heat transfer fluid. -Inlet for the first heat transfer fluid to flow into the circulation chamber. - An outlet for the first heat transfer fluid to flow out of the circulation chamber. - An inlet for the second heat transfer fluid to flow into the circulation chamber. - The outlet for the second heat transfer fluid to flow out of the circulation chamber. - An exchanger block is arranged in a circulation chamber to communicate with the inlet and outlet of the fluid, so as to allow the first fluid and the second fluid to circulate in and through the exchanger block, and to transfer heat between the first fluid and the second fluid.

[0015] The heat exchange device according to the invention is characterized in that it includes at least one interface box, which forms one of the inlets or outlets of a fluid. The interface box includes a dome-shaped housing and an interface frame. The dome-shaped housing is provided with an orifice adapted for connection to a supply or distribution conduit for a heat transfer fluid. The interface frame is mechanically connected to the outer housing. The orifice and the interface frame each extend in a plane perpendicular to a longitudinal axis, which defines the primary circulation direction of the fluid flow at the inlet or outlet of the box. The box also includes a plurality of guide fins for the heat transfer fluid, each extending between the orifice and the interface frame to ensure geometric continuity between the conduit and the exchanger block. The fins are also separated from each other to form passages between the fins to allow pressure forces to be transmitted to the dome-shaped housing of the interface box.

[0016] Therefore, the heat exchange device according to the invention enables the limitation of pressure loss in the interface box by improving fluid flow through the interface box and eliminating abrupt changes in geometry inherent in the change of cross-section between the supply or distribution pipes and the interface frame of the box. The interface box is equipped with multiple guide fins (i.e., at least two different guide fins), and the interface frame is mechanically connected to the exchanger block. The guide fins, in particular, enable the elimination of edge eddies that can arise due to breaks in the geometry of the box through which the heat transfer fluid flows.

[0017] Each of the multiple fins extends between the orifice and the interface frame.

[0018] Furthermore, as long as the box itself is not modified relative to existing exchangers, the box can maintain its mechanical resistance to pressure and stress.

[0019] Furthermore, guide fins can help absorb the mechanical stress experienced by the enclosure. Where appropriate, enclosures thinner than those in the prior art can be provided, thereby allowing for better thermomechanical properties by reducing thermal inertia.

[0020] The box includes multiple guide fins, that is, at least two different fins, and the box can be adapted to the environment in which it is arranged.

[0021] As an example and according to one embodiment, the presence of multiple fins within the box allows for the provision of fins with shapes different from the other fins, thereby enabling the limitation of pressure loss in the box associated with breakage in the geometry of the pipe, for example if the box happens to have a bend before the inlet orifice.

[0022] Furthermore, according to the invention, the fins are separated from each other to form air passages between the fins. These passages allow pressure forces to be transmitted to the dome-shaped outer shell of the interface box, which is better suited to withstand these stresses than the convex fins provided in the box.

[0023] An interface box can be the inlet box of an exchanger, in which case it is usually referred to by the terms distribution box or distributor. This box is supplied with a heat transfer fluid inlet pipe that leads to the box at an orifice, which in turn becomes the box's inlet orifice. The distribution box allows heat transfer fluid to be distributed to the exchanger blocks from the inlet orifice. The presence of multiple guide fins in such a box forms a divergent guiding device for the heat transfer fluid to flow to the exchanger blocks.

[0024] An interface box can also be the outlet box of an exchanger, in which case the term "collector box" or "collector" is often used to refer to it. This box is supplied by the exchanger block and collects the heat transfer fluid from the exchange matrix to supply pipes connected to an orifice of the box, which in turn becomes the box's outlet orifice. Therefore, the collection box allows heat transfer fluid to be conveyed from the exchanger block toward the outlet orifice. The presence of guide fins in such a box forms a converging guide for the heat transfer fluid to flow toward the box's outlet orifice.

[0025] Advantageously, and according to the invention, for at least one interface housing, the orifice is circular, and the interface frame is rectangular, the surface area of ​​the interface frame being larger than the surface area of ​​the orifice, and at least one guide fin—preferably each guide fin—extends longitudinally and radially in the space of the dome-shaped housing that is not facing the orifice.

[0026] According to this advantageous variant, the orifice of the box has a circular cross-section to correspond to a pipe with a circular cross-section, which is supplied by or to the orifice of the interface box. Furthermore, the interface frame has a rectangular cross-section to correspond to an exchanger block with a rectangular cross-section, such as a plate exchanger block. In this case, and preferably, at least one guide fin, and preferably each fin, extends longitudinally and radially in the space of the dome-shaped shell of the box not facing the orifice. This allows for the limitation of breaks in the geometry of the heat transfer fluid flow by not obstructing the space facing the orifice of the box. According to this variant, the guide fins enable the majority of the heat transfer fluid flow to be maintained in the central part of the box by preventing fluid from flowing near the dome-shaped portion of the interface box.

[0027] Advantageously, and according to the invention, for at least one interface box, at least one guide fin—preferably for each guide fin—has a convex shape and extends longitudinally and radially from the orifice to the interface frame.

[0028] According to this variant, the convex shape of the guide fins ensures the continuity of the geometry between the orifice and the interface frame, thus preventing any abrupt changes in fluid flow within the interface box.

[0029] Advantageously, and according to the invention, at least one interface box and the guide fins housed in the interface box are metallic, and the fins are welded to the box.

[0030] According to this advantageous variant, the guide fins are metallic and welded into an interface box that is itself metallic. For example, the convex fins may be stamped metal sheet components that are welded into an interface box formed of stamped metal sheet components themselves.

[0031] According to another variant, the fins can be simply assembled between the interface box and the switch block. The fins are then housed in the interface box but not secured to it.

[0032] Advantageously, and according to the invention, for at least one interface box, at least one guide fin has a shape different from the other fins of the box.

[0033] According to this variant, at least one of the multiple fins has a shape different from the other fins of the housing. For example, this allows for limiting pressure loss in the housing associated with breaks in the geometry of the pipe to which it is connected. As an example, if the supply pipe of the interface housing (in the case of an inlet housing for an exchanger) has a bend just before the inlet orifice, a fin with a specific geometry (and therefore different from the other fins) allows for airflow to be directed toward the exchanger block while limiting pressure loss despite strong turbulence generated upstream of the housing by the bend. For example, this specific shape could consist of the curvature of the convex portion of the fin, which is larger or smaller than the other fins in the housing.

[0034] Advantageously, and according to the invention, at least one guide fin of at least one interface box—preferably each guide fin—carries a heat recovery element that extends within the box to improve the thermomechanical properties of the box.

[0035] According to this advantageous variant, the fins also support heat recovery elements, for example, formed of pins extending in the circulation area of ​​the heat transfer fluid. Therefore, these heat recovery elements will be able to capture a portion of the heat from the heat transfer fluid circulating in the chamber, which will improve the thermomechanical properties of the chamber. In the case of an inlet chamber, this will particularly enable the limitation of the thermal inertia of the exchanger block arranged downstream of the chamber.

[0036] Advantageously, and according to the invention, at least one interface box includes four separate guide fins, which are regularly distributed around the longitudinal axis.

[0037] According to this advantageous variant, the fins are regularly distributed around the longitudinal axis and spaced apart from each other to form passages between the fins. These passages allow pressure forces to be transmitted to the dome-shaped outer shell of the interface box, which is better suited to withstand these stresses than the convex fins provided in the box.

[0038] Advantageously, and according to the invention, the exchanger includes at least one interface box referred to as a distribution box and at least one interface box referred to as a collection box, the distribution box forming an inlet for the first heat transfer fluid and the collection box forming an outlet for the first heat transfer fluid.

[0039] According to this variant, the switch includes interface boxes that serve as inlet boxes and interface boxes that serve as outlet boxes. A switch with four interface boxes can also be provided, one interface box per inlet and one interface box per outlet. All combinations are possible depending on the requirements.

[0040] The present invention also relates to a heat exchange device, characterized by a combination of all or some of the features mentioned above or below. Attached Figure Description

[0041] Other objects, features, and advantages of the invention will become apparent upon reading the following description, which is given by way of non-limiting example only and with reference to the accompanying drawings, in which: Figure 1 This is a schematic perspective view of a heat exchanger according to an embodiment of the present invention. Figure 2 This is a schematic cross-sectional view of a prior art exchanger, where the interface box lacks guide fins for the heat transfer fluid. Figure 3 This is a schematic cross-sectional view of a switch according to an embodiment of the present invention, wherein the interface housing of the switch is equipped with guide fins. Figure 4 This is a schematic view of the interface box of a switch according to an embodiment of the present invention. Detailed Implementation

[0042] For illustrative and clarity purposes, dimensions and proportions are not strictly adhered to in the drawing.

[0043] In all figures, consistent, similar, or analogous elements are represented by the same reference numerals.

[0044] Figure 1A heat exchanger according to an embodiment of the present invention is schematically shown in perspective. The heat exchanger includes an outer housing 10 that defines a circulation chamber 12 for a heat transfer fluid. The chamber 12 is particularly located in... Figure 3 The heat transfer fluid can be of all types. For example, the heat transfer fluid can be a hot air flow, such as a hot air flow drawn from the propulsion engine of an aircraft, and a cold air flow, such as a cold air flow drawn from the outside of an aircraft through a dedicated opening.

[0045] The heat exchanger also includes an interface box 20 forming an inlet and an interface box 30 forming an outlet, the inlet being for a first heat transfer fluid (e.g., a hot air flow) to flow into the circulation chamber, and the outlet being for the first heat transfer fluid to flow out of the circulation chamber.

[0046] The exchanger also includes an interface box 40 forming an inlet and an outlet, the inlet for a second heat transfer fluid (e.g., a flow of cold air) to flow into the circulation chamber, and the outlet for the second heat transfer fluid to flow out of the circulation chamber. The outlet is located at... Figure 1 The exit is not visible in the perspective view; it is positioned on a hidden surface of the perspective view.

[0047] According to other embodiments, the exchanger may include a single interface housing to form an inlet or outlet for fluid. Any construction is possible without questioning the principles of the invention. This will be discussed later. Figure 3 and Figure 4 Describe the structure of the interface box.

[0048] The exchanger also includes a parallelepiped exchanger block 14, which is arranged in the circulation chamber 12. This exchanger block 14 is in fluid communication with both the inlet and outlet fluids, ensuring heat exchange between the two fluids. For example, the exchanger block is formed by a stack of parallel plates 16, which alternately define circulation channels for the first and second heat transfer fluids. Therefore, heat exchange can occur between the two fluids within the chamber 12 through conduction by the plates defining the different channels.

[0049] Figure 4 Interface box 20 is schematically shown, forming a fluid inlet into chamber 12. However, it should be noted that, according to one embodiment, other interface boxes (if the exchanger is in...) Figure 1 (As in the example, including multiple interface boxes) can include those from... Figure 4 The interface box 20 is consistent with the structure shown.

[0050] As in Figure 3 and Figure 4As shown in the diagram, the interface box 20 includes a dome-shaped housing 24 with a circular orifice 26, which is mechanically and fluidly connected to a supply conduit 18 for heat transfer fluid. The supply conduit 18 is cylindrical and has a circular cross-section. The interface box 20 also includes an interface frame 28, which is mechanically connected to the outer housing 10 and fluidly connected to the exchanger block 14. In other words, the interface box 20 allows heat transfer fluid to be received through the orifice 26 and directed toward the interface frame 28 to supply the exchanger block 14 of the exchanger.

[0051] Of course, such an interface box can also form a fluid outlet and is therefore intended to receive fluid from the exchanger block 14 through the interface frame and deliver the fluid toward the orifice 26, which in turn is an outlet orifice, which is fluidly and mechanically connected to the fluid distribution pipe.

[0052] according to Figure 4 The interface box 20 of the embodiment also includes a plurality of guide fins 22a, 22b, 22c, 22d for heat transfer fluid. Each fin 22a, 22b, 22c, 22d extends between the orifice 26 and the interface frame 28 to ensure the continuity of the geometry between the pipe 18 and the exchanger block 14.

[0053] As in Figure 4 As shown in the diagram, the fins are regularly distributed around an axis called the longitudinal axis L, which corresponds to the main flow direction of the fluid through the interface box.

[0054] The guide fins are separated from each other to form passages 30, 31 between the guide fins. These air passages allow pressure forces to be transmitted to the dome-shaped housing 24 of the interface box.

[0055] According to the embodiment shown in the figure, the fins have a convex shape and extend longitudinally and radially within the space defined by the dome-shaped shell 24.

[0056] For example, fins 22a, 22b, 22c, and 22d are formed from stamped metal sheet components and welded inside the interface box.

[0057] The guide fins 22a, 22b, 22c, and 22d enable the elimination of edge vortices, which can be generated due to the disruption of the geometry of the flow of heat transfer fluid through the box.

[0058] Figure 2 The diagram schematically illustrates the airflow through an exchanger, wherein the interface box 20' forming the inlet box and the interface box 30' forming the outlet box each lack guide fins; and Figure 3The diagram schematically illustrates the airflow through a switch according to an embodiment of the invention, wherein interface boxes 20 and 30 of the switch are each provided with guide fins.

[0059] exist Figure 2 It can be observed that there are significant eddies in the inlet interface box 20' and residual eddies in the outlet interface box 30'.

[0060] exist Figure 3 In this configuration, the inlet interface box 20 and the outlet interface box 30 are equipped with guide fins, which allow airflow to be guided between the inlet orifice with a circular cross-section and the parallelepiped exchanger block. Therefore, the fins enable airflow to be guided by eliminating abrupt changes in geometry inherent in the box's supply or distribution pipes and the interface frame, which is mechanically connected to the exchanger block.

[0061] According to an embodiment not shown in the figures, at least one guide fin also carries heat recovery elements extending within the housing to improve the thermomechanical properties of the housing. For example, these heat recovery elements are pins carried by the fins, extending into the fluid flow. Thus, these pins allow a portion of the heat to be captured from the fluid circulating in contact with the fins within the interface housing.

[0062] Heat exchange equipment can be used in a variety of applications, and is particularly, but not exclusively, for air conditioning systems in transportation vehicles such as aircraft.

Claims

1. A heat exchange device for exchanging heat between two heat transfer fluids, the heat exchange device comprising: - The outer casing (10) defines the circulation chamber (12) for the heat transfer fluid. -Inlet (20) for the first heat transfer fluid to flow into the circulation chamber. - for the outlet (30) where the first heat transfer fluid flows out of the circulation chamber. -Inlet (40) for the second heat transfer fluid to flow into the circulation chamber. - An outlet for the second heat transfer fluid to flow out of the circulation chamber. - An exchanger block (14) is arranged in the circulation chamber (12) to communicate with the inlet and outlet of the fluid, so as to allow the first fluid and the second fluid to circulate in and through the exchanger block, and to transfer heat between the first fluid and the second fluid. The heat exchange device is characterized in that it includes at least one interface box (20, 30), which forms one of the inlets or outlets of the fluid. The interface box (20) includes a dome-shaped housing (24) and an interface frame (28). The dome-shaped housing is provided with an orifice (26) adapted to be connected to a supply pipe (18) or distribution pipe of one of the heat transfer fluids. The interface frame is mechanically connected to the outer housing (10). The orifice (26) and the interface frame (28) are each perpendicular to the longitudinal axis. Extending in the plane of (L), the longitudinal axis defines the main circulation direction of fluid flow at the inlet or outlet of the box, the box (20) also includes a plurality of guide fins (22a, 22b, 22c, 22d) for heat transfer fluid, each of the plurality of guide fins extending between the orifice (26) and the interface frame (28) to ensure the geometric continuity between the pipe (18) and the exchanger block (14), the fins are also separated from each other to form a passage between the fins so as to allow pressure forces to be transmitted to the dome-shaped housing of the interface box.

2. The heat exchange device according to claim 1, characterized in that, For at least one interface box (20), the orifice (26) is circular, and the interface frame (28) is rectangular, the surface area of ​​the interface frame being larger than the surface area of ​​the orifice, and at least one guide fin (22a, 22b, 22c, 22d) – preferably each guide fin – extends longitudinally and radially in the space of the dome-shaped housing (24) not facing the orifice (26).

3. The heat exchange device according to claim 1 or 2, characterized in that, For the at least one interface box (20), at least one guide fin—preferably each guide fin—has a convex shape and extends longitudinally and radially from the orifice (26) to the interface frame (28).

4. The heat exchange device according to any one of claims 1 to 3, characterized in that, The at least one interface box (20) and the guide fins (22a, 22b, 22c, 22d) housed in the interface box are metal, and the fins are welded to the box.

5. The heat exchange device according to any one of claims 1 to 4, characterized in that, For the at least one interface box (20), at least one guide fin (22a, 22b, 22c, 22d) has a different shape from the other guide fins.

6. The heat exchange device according to any one of claims 1 to 5, characterized in that, At least one guide fin (22a, 22b, 22c, 22d) of the at least one interface box (20) – preferably each guide fin – carries a heat recovery element that extends within the box to improve the thermomechanical properties of the box.

7. The heat exchange device according to any one of claims 1 to 6, characterized in that, The at least one interface box includes guide fins (22a, 22b, 22c, 22d) that are regularly distributed around the longitudinal axis.

8. The heat exchange device according to any one of claims 1 to 7, characterized in that, The at least one interface box (20) includes four guide fins (22a, 22b, 22c, 22d) which are regularly distributed around the longitudinal axis.

9. The heat exchange device according to any one of claims 1 to 8, characterized in that, The heat exchange device includes at least one interface box (20) referred to as a distribution box and at least one interface box (30) referred to as a collection box, the distribution box forming an inlet for the first heat transfer fluid and the collection box forming an outlet for the first heat transfer fluid.

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