Aerodynamic measuring device

Abstract

Aerodynamic Measuring Device The present invention relates to an aerodynamic measuring device (10) comprising a body (14) including a surface of interest (20). The device (10) is characterized in that the surface of interest (20) includes a conductive layer (32) configured to emit heat when an electric current is applied to this layer (32). Figure for the abstract: Figure 1

Description

Title of the invention: Aerodynamic measuring device

[0001] The present invention relates to an aerodynamic measuring device. Such a device is, for example, part of an aircraft or any other device exposed to aerodynamic flows, such as a wind turbine.

[0002] In a manner known per se, to ensure its mission, an aircraft includes several measuring devices comprising parts that are flush or appendages protruding from the skin of the aircraft.

[0003] These appendages or protruding parts belong for example to probes allowing in particular to measure different aerodynamic parameters of the airflow surrounding the aircraft, such as in particular the total pressure, static pressure, temperature, slippage or the incidence of the airflow in the vicinity of the skin of the aircraft.

[0004] The aircraft may encounter difficult environmental conditions (frost, standing water, etc.). More specifically, frost may form on the aircraft's skin or appendages. Frost formation is particularly problematic for aerodynamic probes, whose profiles can be altered by frost and whose pressure tapping ports can be obstructed. In some cases, frost can also block the movement of at least some moving parts of these probes and / or cause measurement errors if the accretion is not symmetrical, for example. Measuring instruments mounted on pods can also be affected by frost formation.

[0005] The technical problem addressed by this invention is to prevent the formation of frost and to ensure de-icing on the surface of aeronautical measurement equipment.

[0006] Several prior art documents already address this issue at least partially.

[0007] Thus, for example, document FR 2 833 347 describes a heating device for a total pressure probe, implemented using electrical resistors embedded in the appendages. More specifically, this type of probe consists of a mast supporting a tube closed at one end, called a Pitot tube. The probe is heated by means of a heating resistor in the form of a heating wire wound within the probe body, i.e., both in the mast and in the Pitot tube. To make the heating wire, the document proposes an electrical conductor comprising an iron-nickel alloy coated with a mineral insulator such as alumina or magnesia. The insulator is itself coated, for example, with a nickel sheath, allowing the wire to be brazed to the probe body.

[0008] However, this solution has limitations insofar as manufacturing the heating wire and assembling it in the probe requires a series of complex and costly operations. The energy consumption of the wire also remains very high.

[0009] US patent 4,275,603 describes another technique for heating a Pitot tube probe. More specifically, this patent describes the use of a heat pipe supplying thermal energy around the Pitot tube. The return of the heat transfer fluid to a liquid state is ensured through a porous material. This allows the probe to be positioned in any possible orientation on the aircraft skin.

[0010] In practice, this solution offers no industrial advantage due to the difficulty of inserting a porous material into a probe. It also requires design modifications. Manufacturing such a probe is at least as complex as one using a heating wire.

[0011] Finally, document EP 3 581 939 proposes the use of coatings with low ice adhesion, thus allowing the ice to detach more easily from the surface. These coatings are applied to strategic areas where the risk of ice formation is highest. Combined with a heating system, they can reduce the electricity consumption of these systems.

[0012] However, this solution has limitations. It is not a self-contained system. Indeed, when a layer of ice forms, it is still necessary to use a supplementary heating system to defrost it. Furthermore, these coatings are degraded by environmental conditions and their performance is significantly impacted, potentially even becoming less efficient than the substrate.

[0013] The present invention aims to overcome all the drawbacks of the prior art. More particularly, the invention aims to provide means for actively heating an aerodynamic measuring device that can be easily integrated into such a device and that exhibit moderate power consumption, without significant degradation of its properties over time.

[0014] To this end, the invention aims at an aerodynamic measuring device comprising a body including a surface of interest;

[0015] the device being characterized in that the surface of interest comprises a conductive layer configured to emit heat when an electric current is applied to this layer.

[0016] According to other advantageous aspects of the invention, the device comprises one or more of the following features, taken individually or in all technically possible combinations:

[0017] - the conductive layer comprises a pair of contacts arranged at a periphery of these are configured to apply an electric current to the conductive layer;

[0018] - the device further comprising a voltage generator configured to generate a potential difference across the contacts;

[0019] - the contacts are formed at least partially by electrodes and / or ink driver;

[0020] - the conductive layer is formed of a conductive paint or ink and / or of a conductive coating made of a conductive material such as graphene;

[0021] - the surface of interest further comprises an insulation layer disposed between the conductive layer and a substrate forming at least partially the body, and configured to electrically isolate the conductive layer from the substrate;

[0022] - the substrate includes a surface treatment;

[0023] - the insulation notch is further configured to facilitate the attachment of the layer driver;

[0024] - the device further comprising a protective layer disposed on the conductive layer and configured to protect the conductive layer and / or electrically isolate the conductive layer;

[0025] - the or at least one of said layers is disposed by spraying;

[0026] - the device forming an aerodynamic measuring probe or a camera;

[0027] - the body protrudes from or is flush with an external surface of an aircraft.

[0028] The invention will become clearer upon reading the following description, given solely by way of non-limiting example, and made with reference to the drawings in which:

[0029] - [Fig. 1] [Fig. 1] is a schematic view of an aerodynamic measuring device according to the invention, the device comprising a surface of interest;

[0030] - [Fig.2] [Fig.2] is a detailed schematic view of the surface of interest of the [Fig.l];

[0031] - [Fig.3] [Fig.3] is a detailed schematic view of the surface of interest of the [Fig.1], according to a different example from that of [Fig.2].

[0032] Figure 1 illustrates an aerodynamic measuring device 10 according to the invention. This device can be used in any environment exposed to aerodynamic flows.

[0033] In the illustrated example, the aerodynamic measuring device 10 includes an aerodynamic measuring probe. However, in a general case, the aerodynamic measuring device 10 may include any other device, such as a camera for example, positioned protruding from or flush with a surface exposed to aerodynamic flows.

[0034] According to the illustrated example, the device 10 according to the invention makes it possible to measure at least one of the physical values ​​relating to the medium, such as total pressure, static pressure, incidence, temperature, speed, etc.

[0035] More particularly, the device 10 may have an anemobaroclinometric probe which can, for example, measure several of the aforementioned quantities.

[0036] The environment in which the device 10 is exposed is in particular a freezing environment, that is to say an environment in which frost accretions are likely to form outside or inside the device.

[0037] The device 10 is advantageously mounted on the fuselage of an aircraft or on an external part of a wind turbine.

[0038] Aircraft means any pilotable machine capable of moving through the air. In particular, an aircraft may refer to an airplane, a helicopter, or a drone.

[0039] As illustrated in [Fig. 1], the device 10 comprises an internal part 12 and a body 14.

[0040] The internal part 12 includes an electronic module 16 enabling the operation of the device 10. The internal part 12 is advantageously located away from aerodynamic flows, for example in an internal part of the fuselage of the aircraft or wind turbine.

[0041] The body 14 comprises an outer surface 17 exposed to aerodynamic flows. In some examples, the body 14 further comprises an inner surface also exposed at least partially to aerodynamic flows.

[0042] The body 14 is for example fixed on an external surface of the aircraft fuselage or on an external surface of the wind turbine such as a blade.

[0043] The body 14 has or forms a movable or sensitive part that allows the necessary measurements to be taken when exposed to aerodynamic flows. For example, the electronic module 16 is capable of generating measurements (such as angle of attack, for example) as a function of the position of the movable part. In the example of [Fig. 1], the body 14 has a wind vane for the angle of attack probe. According to other examples, the body 14 has a tube, for example a Pitot tube, mounted on a mast away from the aircraft fuselage. This tube has an opening that allows aerodynamic flows to flow inside it, where the pressure can, for example, be measured using techniques known per se.

[0044] The body 14 includes a surface of interest 20 having a surface on which icing must be avoided. According to different embodiments, the surface of interest 20 may correspond to all or part of the outer surface and / or the inner surface of the body 14. For example, in the case of a weather vane, the surface of interest 20 may extend over all or part of an outer surface forming the upper / lower surface and / or a junction surface between the fixed and moving parts of the the weather vane. In the example of a Pitot tube, the surface of interest 20 can extend over all or part of the inner surface of the Pitot tube in contact with the aerodynamic flows.

[0045] To prevent frost formation on the surface of interest 20, the device 10 includes heating means 30. The heating means 30 include a heating active part 32, a pair of contacts 34 arranged in contact with the heating active part 32 and a voltage generator 36 configured to generate a potential difference on the contacts 34.

[0046] The voltage generator 36 is, for example, integrated into the internal part 12 of the device 10. The operation of this voltage generator 36 can, for example, be controlled by the electronic module 16 as a function, for example, of a temperature measured locally near the surface of interest 20. The voltage generator 36 is, for example, connected to an external power supply and allows, for example, the generation of a voltage V between 12 V and 800 V on the contacts 34.

[0047] The contacts 34 are connected to the voltage generator 36 by electrical conduits extending at least partially from the internal part 12 to the body 14 of the device 10. The electrical conduits may be formed at least partially of electrical wires and / or conductive ink.

[0048] According to the invention, the active heating part 32 of the heating means 30 is formed by a conductive layer 32 of the surface of interest 20. This conductive layer 32 extends, for example, over substantially the entire surface of interest 20. Alternatively, the conductive layer 32 extends over at least 30%, preferably over at least 50%, advantageously over at least 60% and even more advantageously over at least 70%, of the area of ​​the surface of interest 20.

[0049] The conductive layer 32 is, for example, formed of a conductive paint or ink, such as graphene ink, paint with conductive particles (carbon, for example), etc. Alternatively or in addition, the conductive layer 32 is formed of a conductive coating made of a conductive material such as graphene.

[0050] The surface of interest 20 and the different layers composing it are illustrated in more detail in [Fig.2].

[0051] Thus, as shown in this [Fig.2], the contacts 34 are for example arranged at the periphery of the conductive layer 32. These contacts 34 are formed at least partially by electrodes and / or conductive ink.

[0052] Furthermore, as also illustrated in [Fig. 2], the surface of interest 20 comprises an insulating layer 41 and a protective layer 42 arranged such that the conductive layer 32 lies between these layers 41, 42. In some embodiments, only one of these layers 41, 42 is present. According to yet others In other embodiments, the surface of interest 20 is devoid of these layers 41, 42.

[0053] Advantageously, each of the layers 41, 42 extends along the entire extent of the conductive layer 32. According to other embodiments, at least one of these layers 41, 42 extends partially along the conductive layer 32.

[0054] The insulating layer 41 is disposed between the conductive layer 32 and a substrate forming at least partially the body 14. In the example of [Fig. 2], the substrate is formed by the outer surface 17 of the body 14. According to other examples, the substrate is formed at least partially by the outer surface 17 and / or the inner surface of the body 14. In the example of [Fig. 3], the outer surface 17 of the body 14 receives a surface treatment (for example, sulfuric anodizing, electroless nickel plating, etc.) which then forms a treatment layer 43 disposed between the outer surface 17 and the insulating layer 41. In some examples, this treatment layer 43 can also provide electrical insulation so that the additional insulating layer 41 is not necessary.

[0055] The insulation layer 41 is configured to electrically insulate the conductive layer 42 from the substrate. Furthermore, the insulation layer 41 is configured to facilitate the adhesion of the conductive layer 32. Finally, in some examples, the insulation layer 41 also provides thermal diffusion. This may be necessary, for instance, when, in addition to heating the exterior, it is required to diffuse heat into the interior of the device 10. In other examples, the insulation layer 41 provides thermal insulation between the conductive layer 32 and the substrate. The material of the insulation layer 41 can be chosen according to the nature of the substrate and / or the conductive layer 32 to ensure better adhesion and / or insulation (thermal and / or electrical) and / or thermal diffusion. In addition, the insulation layer 41 may have a texture adapted to allow the adhesion of the conductive layer 32.

[0056] The protective layer 42 is disposed on the conductive layer 32 and configured to protect the conductive layer 32 and / or electrically insulate this conductive layer 32 from the outside. The material of the protective layer 42 can be chosen according to the nature of the conductive layer 32 to ensure better adhesion and / or insulation.

[0057] The deposition of each layer 32, 41, 42 is preferably carried out by spraying. Alternatively, at least one of these layers 32, 41, 42 is deposited by any other technique such as screen printing, immersion (deep coating), particularly for complex geometries (internal channels). It is also possible to produce such a multilayer system (i.e., the set of three layers 32, 41, 42) in the form of adhesive patches to be placed on the surface of interest.

[0058] The thickness of each layer 32, 41, 42 can be chosen according to the material used and / or the function performed by that layer. For example, the thickness of each layer 32, 41, 42 is between 0.015 µm and 150 µm.

[0059] During operation of the device 10, the electronic module 16 controls the voltage generator 36 based, for example, on an average temperature measured near the surface of interest 20 or by any other means. The voltage generator 36 then generates a potential difference across the contacts 34. This potential difference induces an electric current in the conductive layer 32, which emits heat. The heat is transferred via the protective layer 42 to the outside to defrost the corresponding area. In some cases, the heat is also transferred inside the device 10 via, for example, the layer 41, which forms a thermal diffuser.

[0060] It is therefore understood that the present invention has a number of advantages.

[0061] First, the invention can be implemented in a particularly simple manner since the conductive layer can be easily produced even on surfaces with complex geometries. Furthermore, because the conductive layer can extend over virtually the entire surface of interest, heating can be implemented efficiently, thereby reducing the electrical consumption of the heating means. In addition, various protective means (such as a protective layer) can be used to prevent the degradation of the conductive layer's properties over time.

Claims

Demands

1. Aerodynamic measuring device (10) comprising a body (14) comprising a surface of interest (20); the device (10) being characterized in that the surface of interest (20) comprises a conductive layer (32) configured to emit heat when an electric current is applied to this layer (32).

2. Device (10) according to claim 1, wherein the conductive layer comprises a pair of contacts (34) disposed at a periphery thereof and configured to apply an electric current to the conductive layer (32).

3. Device (10) according to claim 2, further comprising a voltage generator (36) configured to generate a potential difference on the contacts (34).

4. Device (10) according to claim 2 or 3, wherein the contacts (34) are formed at least partially by electrodes and / or conductive ink.

5. Device (10) according to any one of the preceding claims, wherein the conductive layer (32) is formed of a conductive paint or ink and / or a conductive coating formed of a conductive material such as graphene.

6. Device (10) according to any one of the preceding claims, wherein the surface of interest (20) further comprises an insulation layer (41) disposed between the conductive layer (32) and a substrate forming at least partially the body (14), and configured to electrically insulate the conductive layer (32) from the substrate; advantageously, the substrate comprises a surface treatment.

7. Device (10) according to claim 6, wherein the insulation notch (41) is further configured to facilitate the attachment of the conductive layer (32).

8. Device (10) according to any one of the preceding claims, further comprising a protective layer (42) disposed on the conductive layer (32) and configured to protect the conductive layer (32) and / or electrically isolate the conductive layer (32).

9.

10.

11. Device (10) according to any one of the preceding claims, wherein the or at least one of said layers (32, 41, 42) is disposed by spraying. Device (10) according to any one of the preceding claims, forming an aerodynamic measuring probe or a camera. Device (10) according to any one of the preceding claims, wherein the body (14) protrudes from or is flush with an external surface of an aircraft.

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