Heated leading edge structure for aircraft, slat, wing and aircraft

Abstract

The invention relates to a heated leading edge structure for an aircraft, a slat, a wing and an aircraft. A heated leading edge structure (14) for an aircraft (10) includes a leading edge panel (20) having an outer surface (32) configured for contact with an ambient flow (A) and an inner surface (34) opposite the outer surface (32); a reinforcing member (22) connected to the inner surface (34) of the leading edge panel (20); and a heating device (24) configured to heat the leading edge panel (20); the heating device (24) comprises at least one indirect heating device (44) mounted on the reinforcing member (22), said indirect heating device (44) being configured for heating the leading edge panel (20) at least by means of conduction through the reinforcing member (22).

Description

Technical Field

[0001] The present disclosure relates to a heated leading edge structure for an aircraft. The present disclosure also relates to a slat including such a heated leading edge structure and a wing including such a slat and / or such a heated leading edge structure. The present disclosure also relates to an aircraft including such a wing and / or such a slat and / or such a heated leading edge structure. Background Art

[0002] In the field of heated leading edge structures, it is known to use heating devices designed to heat the leading edge panels. These devices are crucial for preventing ice accumulation on the leading edge panels of structures. Ice accumulation on the leading edge panels of aircraft significantly affects aircraft performance. Therefore, heating devices for leading edge structures are crucial for ensuring safe aircraft operation.

[0003] In known heated leading edge structures, it is for example known to use bleed air introduced into the cavity formed by the leading edge panels in order to heat the air in the cavity and thus the leading edge structure. However, such heating relies on complex and cumbersome heating equipment.

[0004] Alternative solutions have therefore been developed to reduce the complexity and weight of the heating devices and, in general, the heated leading edge structure. The proposed solutions rely, for example, on heating devices, such as electric heating devices, arranged directly on the leading edge panels of the leading edge structure. Such devices provide direct heating of the leading edge panels and ensure a simple and lightweight heated leading edge structure for an aircraft.

[0005] However, the known leading edge devices mentioned above are not entirely satisfactory. Such systems are complex and cumbersome, or they provide uneven heating of the leading edge panel, leading to the appearance of undesirable cold spots. This is the case, for example, when the heated leading edge structure includes a reinforcement member that prevents the leading edge panel from being heated in the connection area between the reinforcement member and the heating device. Summary of the Invention

[0006] It is therefore an object of the present invention to provide a heated leading edge structure for an aircraft which is simple and lightweight and which is not subject to local ice accumulation.

[0007] To this end, the present invention relates to a heated leading edge structure for an aircraft, the heated leading edge structure comprising:

[0008] a leading edge panel having an outer surface configured for contact with an ambient flow and an inner surface opposite the outer surface,

[0009] - a reinforcement member connected to the inner surface of the leading edge panel, and

[0010] - a heating device configured to heat the leading edge panel;

[0011] Therein, the heating arrangement comprises at least one indirect heating device mounted on the reinforcement member, the indirect heating device being configured for heating the leading edge panel at least by means of conduction through the reinforcement member.

[0012] The use of indirect heating devices mounted on the reinforcement members and configured for heating the leading edge panels at least by conduction through the reinforcement members is particularly advantageous as this allows heating of the leading edge panels specifically in typical cold spot areas, thereby helping to homogenise the heating across the leading edge panels.

[0013] According to further advantageous aspects of the invention, the heated leading edge structure comprises one or more of the following features alone or in all technically possible combinations:

[0014] - The indirect heating device is detachably mounted on the reinforcement member;

[0015] - the indirect heating device is formed as a heater mat;

[0016] - the reinforcement member comprises a web portion extending orthogonally to the leading edge panel, the indirect heating device being mounted on said web portion;

[0017] - the reinforcement member comprises a flange portion extending over the inner surface of the leading edge panel to connect the reinforcement member to said inner surface;

[0018] - the heated leading edge structure further comprises a plurality of fasteners connected to the reinforcement member, the indirect heating device being configured to cooperate with said fasteners for mounting on the reinforcement member;

[0019] - the heated leading edge structure further comprises an adhesive layer, the indirect heating device being connected to the reinforcement member by the adhesive layer;

[0020] - the heating arrangement further comprises at least one direct heating device mounted on the inner surface of the leading edge panel;

[0021] -The heating device also includes:

[0022] - at least one temperature sensor; and

[0023] - a control unit connected to at least one temperature sensor, the control unit

[0024] Yuan includes:

[0025] + an acquisition module configured to acquire temperature information from at least one temperature sensor, and

[0026] + a control module configured to control at least one indirect heating device based on the collected temperature information;

[0027] - the control module is further configured to control at least one direct heating device based on the collected temperature information;

[0028] - the heating device comprises a plurality of temperature sensors, the control module being configured to control the direct heating device or the indirect heating device independently of at least one of the other; and

[0029] -Temperature sensor:

[0030] - is configured to measure the temperature of one of the heating devices, or

[0031] - configured to measure the temperature of the inner surface of the leading edge panel, or

[0032] - configured to measure the ambient temperature in a cavity defined by the inner surface of the leading edge panel.

[0033] The invention also relates to a slat comprising a heated leading edge structure as presented above.

[0034] The invention also relates to a wing comprising a heated leading edge structure as presented above and / or a slat as presented above.

[0035] The invention also relates to an aircraft comprising a heated leading edge structure as mentioned above and / or a slat as mentioned above and / or a wing as mentioned above. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The invention will be better understood on reading the following description, given by way of example only and with reference to the accompanying drawings, in which:

[0037] - Figure 1 is a schematic diagram of an aircraft including a heated leading edge structure according to the present invention;

[0038] - Figure 2 yes Figure 1 A schematic detailed view of the heated leading edge structure is presented, wherein the direct heating device is not shown;

[0039] - Figure 3 yes Figure 1 and Figure 2 a cross-sectional view of the heated leading edge structure presented, wherein the direct heating device is illustrated; and

[0040] - Figure 4 is based on Figures 1 to 3Schematic diagram of a heated leading edge structure, wherein the control unit and sensors of the heated leading edge structure are visible. DETAILED DESCRIPTION

[0041] Reference Figure 1 , the aircraft 10 includes a wing 12 including a heated leading edge structure 14. In particular, Figure 1 In the example presented in FIG, the wing 12 comprises a fixed wing portion 16 and a slat 18 that is movable relative to the fixed wing portion 16. In this example, the slat 18 comprises a heated leading edge structure 14. The heated leading edge structure 14 then defines the leading edge of the slat 18, for example.

[0042] In other or complementary examples, the fixed wing section 16 includes a heated leading edge structure 14. The heated leading edge structure 14 then defines, for example, a leading edge of the fixed wing section 16.

[0043] The aircraft 10 is, for example, an airplane, and preferably a passenger aircraft.

[0044] As from Figure 2 and Figure 3 As can be seen, the heated leading edge structure 14 includes a leading edge panel 20, a reinforcement member 22, and a heating device 24. The heated leading edge structure 14 also includes a plurality of fasteners 26 and an adhesive layer 28, for example.

[0045] As presented in greater detail later, a plurality of fasteners 26 and / or adhesive layer 28 are configured, for example, to connect the reinforcement member 22 and the heating device 24 .

[0046] The leading edge panel 20 is preferably made of a metallic material such as aluminum, steel or titanium, but may also be formed of other materials such as a fiber reinforced plastic material.

[0047] The leading edge panel 20 includes an outer surface 32 and an inner surface 34 .

[0048] The outer surface 32 is configured for contact with an ambient flow A. The ambient flow is notably the flow in which the aircraft 10 evolves, ie the air outside the aircraft 10 .

[0049] The inner surface 34 is opposite the outer surface 32 . In other words, the outer surface 32 and the inner surface define opposite surfaces of the leading edge panel 20 .

[0050] As from Figure 2 It can be seen that the inner surface 34 defines, for example, the cavity C of the leading edge panel 20 .

[0051] The reinforcement member 22 is preferably made of a metallic material such as aluminum, steel, or titanium, but may be formed of other materials.

[0052] The reinforcement member 22 preferably has a very high thermal conductivity, for example a thermal conductivity higher than 50 W / m*K, preferably higher than 100 W / m*K, further preferably higher than 150 W / m*K.

[0053] The reinforcement member 22 is connected to the inner surface of the leading edge panel 20. The reinforcement member 22 extends in the cavity C defined by the leading edge panel 20, for example.

[0054] In an example not shown, an intermediate element such as a seal, a gasket or an adhesive layer is arranged between the reinforcement member 22 and the inner surface 34 of the leading edge panel 20. The intermediate element connects the reinforcement member 22 and the inner surface 34 of the leading edge panel 20, for example.

[0055] The intermediate element is made of, for example, a non-metallic material.

[0056] The intermediate element preferably has a high thermal conductivity, for example a thermal conductivity higher than 0.2 W / m*K, preferably higher than 0.5 W / m*K, further preferably higher than 1 W / m*K.

[0057] The reinforcement member 22 is, for example, a spar 36 or a rib 38 of the aircraft 10. In particular, the reinforcement member 22 is, for example, a spar 36 or a rib 38 of the wing 12 or the slat 18.

[0058] In the remainder of the description it will be understood that the spars of the wing / slat extend substantially in the direction of elongation of the wing / slat and that the ribs of the wing / slat extend substantially in the chordwise direction of the wing / slat.

[0059] like Figure 2 As presented in FIG, the heated leading edge structure 14 includes, for example, a plurality of reinforcing members 22. In particular, in Figure 2 In the example shown, the plurality of reinforcement members 22 include at least one spar 36 and one rib 38 .

[0060] like Figure 3 As illustrated in FIG, the reinforcement member 22 includes, for example, a web portion 40 and a flange portion 42 .

[0061] The web portion 40 extends, for example, substantially normal to the leading edge panel 20 .

[0062] When the reinforcement member 22 is a spar, the web portion 40 extends, for example, along a plane substantially parallel to the elongation direction of the wing / slat. When the reinforcement member 22 is a rib, the reinforcement web portion extends, for example, along a plane substantially parallel to the chord direction of the wing / slat.

[0063] The flange portion 42 extends, for example, on the inner surface 34 of the leading edge panel 20. Specifically, the flange portion 42 extends, for example, on the inner surface 34 of the leading edge panel 20 to connect the reinforcement member 22 to the inner surface 34 of the leading edge panel 40. The flange portion 42 is fastened to the inner surface 34, for example.

[0064] The heating device 24 is configured to heat the leading edge panel 20 .

[0065] As from Figures 2 to 4 As can be seen, the heating device 24 comprises at least one indirect heating device 44. Figure 3 and Figure 4 As shown in FIG, the heating device 24 also preferably includes at least one direct heating device 46. In addition, as shown in FIG. Figure 4 As shown in FIG. 2 , the heating device 24 further includes, for example, at least one temperature sensor 48 and a control unit 50 .

[0066] As from Figures 2 to 4 As can be seen, the indirect heating device 44 is mounted on the reinforcement member 22. For example, and as presented in more detail below, the indirect heating device 44 is mounted on the reinforcement member in a detachable manner. In other words, the indirect heating device 44 can be removed from the reinforcement member 22, for example, and can be replaced without damaging the indirect heating device 44 and / or the reinforcement member 22.

[0067] For example and as from Figure 3 As can be seen, the indirect heating device 44 is mounted on the web portion 40 of the reinforcement member 22. In an alternative, not shown embodiment, the indirect heating device 44 is mounted on the flange portion 42 of the reinforcement member 22, for example.

[0068] The indirect heating element 44 is configured to heat the leading edge panel 20 at least by conduction through the reinforcement member 22. In other words, heat generated by the indirect heating device 44 is conducted through the reinforcement member 22 to the leading edge panel 20 when the indirect heating element is operating.

[0069] The indirect heating device 44 is, for example, also configured to heat the air enclosed within the cavity C defined by the leading edge panel 20 and to then heat the leading edge panel 20 by convection.

[0070] As from Figures 2 to 4 As can be seen, the indirect heating device 44 is formed as a heater mat and is, for example, an electric heater mat. The indirect heating device 44 is, for example, configured to output more than 100 W / m in the form of heat. 2 .

[0071] The indirect heating device 44 is, for example, flexible to avoid delamination when the leading edge panel 20 is subjected to minor impacts.

[0072] exist Figure 3 , the heated leading edge structure 14 includes a plurality of fasteners 26 and an adhesive layer 28 for fastening the indirect heating device 44 to the reinforcement member 22. In other embodiments, the heated leading edge structure 14 includes a plurality of fasteners 26 or an adhesive layer 28 for fastening the indirect heating device 44 to the reinforcement member 22.

[0073] like Figure 3 As presented in FIG, the indirect heating device 44 is connected to the reinforcement member by means of an adhesive layer 28 .

[0074] Preferably, adhesive layer 28 is flexible to avoid delamination upon minor impact.

[0075] Furthermore, the adhesive layer 28 preferably has a high thermal conductivity, preferably higher than 0.2 W / m*K, further preferably higher than 0.5 W / m*K, for transferring heat from the indirect heating device 44 to the reinforcement member 22 in an efficient and possibly unhindered manner.

[0076] The adhesive layer 28 also preferably has a relatively low adhesive strength, preferably an adhesive strength below 0.4 N / mm (force in N per heater device width in mm), to allow easy, ideally non-destructive, removal of the indirect heating device 44. In particular, the chemical composition of the adhesive layer is adjusted so that it allows the indirect heating device 44 to be peeled off from the leading edge panel with a low force, preferably with a force in the range of below 0.4 N / mm.

[0077] Adhesive layer 28 is also preferably formed to have temperature dependence. Specifically, adhesive layer 28 is formed in such a manner that it maintains the load spectrum for normal aircraft operation, but at elevated temperatures above the operating temperature window, such as above 100° C., which may be applied when removing indirect heating device 44 during maintenance, adhesive layer 28 becomes sufficiently weak when indirect heating device 44 is to be removed that indirect heating device 44 can be peeled off from reinforcement member 22 by hand or with a tool with a peel force of less than 0.4 N / mm.

[0078] exist Figure 3 In the example of FIG. 4 , the fastener 26 is connected to the reinforcement member 22 . The indirect heating device 44 is configured to cooperate with the fastener 26 to be mounted on the reinforcement member 22 .

[0079] Each fastener 26 is attached to the reinforcement member 22, for example by adhesive, and engages the indirect heating device 44. To this end, each fastener 26 comprises, for example, a pin 52 extending away from the reinforcement member 22 and engaging a hole (not shown) in the indirect heating device 44. The pin 52 is provided, for example, at its free end with a retaining device (not shown) for retaining and fixing the pin 5 in the hole (not shown).

[0080] As from Figure 3 and Figure 4 As can be seen, the direct heating device 46 itself is similar to the indirect heating device 4. In particular, the direct heating device 46 differs from the indirect heating device 44 only in that the direct mounting device 46 is mounted on the leading edge panel 20, preferably on the inner surface 34 of the leading edge panel 20, rather than on the reinforcement member 22. Thus, the direct heating device 46 is configured for directly heating the leading edge panel 20, for example, by direct conduction.

[0081] In particular and as from Figure 3 As can be seen, the direct heating device 46 is also mounted in a detachable manner relative to the rest of the heated leading edge structure 24 and in particular relative to the leading edge panel 20 .

[0082] To this end, the heated leading edge structure 14 comprises, for example, a further fastener 26 and / or an adhesive layer 28 as presented above for fastening the direct heating device 46 to the leading edge panel 20 .

[0083] The temperature sensor 48 is configured to measure temperature information Tm. Figure 4 , the temperature sensor 48 is arranged in the cavity C defined by the inner surface 34 of the leading edge panel 20. In alternatives and for example, the temperature sensor 48 is arranged on the indirect heating device 44, on the direct heating device 46, on the leading edge panel 20 or on the reinforcement member 22.

[0084] The temperature sensor 48 is configured, for example, to measure the temperature of one of the heating devices, i.e., one of the indirect heating devices 44 or one of the direct heating devices 46. In an alternative, the temperature sensor 48 is configured to measure the temperature of the inner surface 34 of the leading edge panel 20. In another alternative, the temperature sensor 48 is configured to measure the ambient temperature in the cavity C defined by the inner surface 34 of the leading edge panel 20.

[0085] like Figure 4 As shown in FIG. 1 , the heating device 24 includes, for example, a plurality of temperature sensors 48 .

[0086] The control unit 50 of the heating device 24 is connected to the at least one temperature sensor 48 .

[0087] As from Figure 4 It can be seen that the control unit 50 includes a collection module 56 and a control module 58 .

[0088] The acquisition module 56 is connected to the temperature sensor 48 and is configured to acquire temperature information Ta from at least one temperature sensor. For example, the temperature information Ta acquired from the acquisition module corresponds to and / or is the same as the temperature information Tm measured by the temperature sensor 48 or each temperature sensor 48.

[0089] The control module 56 is configured to control the at least one indirect heating device 44 according to the collected temperature information Ta. In addition and for example, the control module 56 is also configured to control the at least one direct heating device 46 according to the collected temperature information Ta.

[0090] The control module 56 is configured, for example, to control the direct heating device 44 or the indirect heating device 46 independently of at least one of the direct heating device 46 or the indirect heating device 46, preferably depending on the temperature information Ta acquired from the plurality of temperature sensors 48. In other words, each heating device 44, 46 is independently controlled by the control module 56, for example.

[0091] In order to control the direct heating device 46 and / or the indirect heating device 44 , the control module 56 is, for example, configured to store and / or obtain power profiles for said heating devices 44 , 46 .

[0092] The power profile is configured, for example, to provide a control law for power output to each of the direct heating device 46 and / or the indirect heating device 44 based on the collected temperature information Ta. The power profile is particularly configured to control the power output to each of the direct heating device 46 and / or the indirect heating device 44 so that the collected temperature Ta reaches and / or maintains the target temperature Tt.

[0093] For example, the power distribution for the direct heating device 46 and the indirect heating device 44 is different. Preferably, the power distribution for each of the direct heating device 46 and the indirect heating device 44 is different and is selected for example for uniform heating of the leading edge panel 20.

[0094] exist Figure 4 In the example of FIG. 5 , the control unit 50 is formed as an information processing unit 60 comprising, for example, a memory 62 associated with a processor 64 .

[0095] exist Figure 4 In the example of FIG, the acquisition module 56 and the control module 58 are each produced in the form of software that can be executed by the processor 64. Then, the memory 62 can store the acquisition software designed to acquire temperature information Ta from the at least one temperature sensor 48 and the control software designed to control the at least one indirect heating device 44 according to the acquired temperature information Ta. Then, the processor 64 of the information processing unit 60 can execute the acquisition software and the control software.

[0096] In a variant (not shown), the acquisition module 56 and the control module 58 are each produced in the form of a programmable logic component, such as an FPGA (field programmable gate array) or in the form of a dedicated integrated circuit, such as an ASIC (application-specific integrated circuit) or in the form of any combination of ASIC, FPGA and / or software.

[0097] In another variation (not shown), the acquisition module 56 and the control module 56 are each implemented as analog signal processing devices.

[0098] When the control unit 50 is configured in the form of one or more software programs, i.e., in the form of a computer program, it can also be stored on a medium that can be read by a computer (not shown). A computer-readable medium is, for example, a medium that is suitable for storing electronic instructions and can be coupled to a bus of a computer system. As an example, the readable medium is an optical disc, a magneto-optical disc, a ROM memory, a RAM memory, any type of non-volatile memory (e.g., EPROM, EEPROM, FLASH, NVRAM), a magnetic card, or an optical card. The computer program including the software instructions is then stored on the readable medium.

[0099] As presented previously, the use of an indirect heating device 44 configured for heating the leading edge panel 20 at least by conduction through the reinforcement member 22 is particularly relevant to homogenizing the heating across the leading edge panel while keeping the leading edge panel simple and lightweight.

[0100] Furthermore, having the indirect heating apparatus 44 removably mounted on the reinforcement member 22 is particularly advantageous for allowing quick and easy maintenance of the heated leading edge structure 14 .

[0101] The use of an indirect heating device 44 formed as a heater mat is particularly advantageous for having an efficient, compact and lightweight heating arrangement 24 .

[0102] Arranging the indirect heating device 44 on the web portion of the reinforcement member 22 and having the flange portion 42 of the reinforcement member 22 connect the reinforcement member 22 to the inner surface 34 of the leading edge panel 20 are two advantageous aspects that improve the integration of the heating device 24 in the heated leading edge structure 14 while improving the heat transfer between the indirect heating device 44 and the leading edge panel 20.

[0103] The fasteners 26 and adhesive layer 28 described above are particularly advantageous for providing a heated leading edge structure 14 that can be easily maintained.

[0104] The combined use of the direct heating device 46 and the indirect heating device 44 provides a simple and effective heating means for the heated leading edge structure 14 .

[0105] Having a heated leading edge structure including at least one temperature sensor 48 and a control unit 50 is particularly beneficial for improving the efficiency and accuracy of the heating of the leading edge panel 20 , and also improves the safety of the operation of the heated leading edge structure 14 .

[0106] Controlling at least one of the direct heating device 46 or the indirect heating device 44 independently of the other of the direct heating device 46 or the indirect heating device 44 is also particularly beneficial for improving the heating accuracy of the heating device 24 and, thereby, improving the performance of the heating device 24 .

Claims

1. A heated leading edge structure (14) for an aircraft (10), the heated leading edge structure (14) comprising: a leading edge panel (20) having an outer surface (32) configured for contact with an ambient flow (A) and an inner surface (34) opposite the outer surface (32), a reinforcement member (22) connected to the inner surface (34) of the leading edge panel (20), and a heating device (24) configured to heat the leading edge panel (20); Characterized in that the heating arrangement (24) comprises at least one indirect heating device (44) mounted on the reinforcement member (22), the indirect heating device (44) being configured for heating the leading edge panel (20) at least by means of conduction through the reinforcement member (22).

2. The heated leading edge structure (14) according to claim 1, wherein The indirect heating device (44) is detachably mounted on the reinforcing member (22).

3. The heated leading edge structure (14) according to claim 1 or 2, wherein: The indirect heating device (44) is formed as a heater mat.

4. A heated leading edge structure (14) according to any one of the preceding claims, wherein The reinforcing member (22) includes a web portion (40) extending orthogonally to the leading edge panel (20), and the indirect heating device (44) is mounted on the web portion (40).

5. A heated leading edge structure (14) according to any one of the preceding claims, wherein The reinforcement member (22) includes a flange portion (42) extending over the inner surface (34) of the leading edge panel (20) to connect the reinforcement member (22) to the inner surface (34).

6. The heated leading edge structure (14) according to any one of the preceding claims, further comprising a plurality of fasteners (26) connected to the reinforcing member (22), the indirect heating device (44) being configured to cooperate with the fasteners (26) to be mounted on the reinforcing member (22).

7. The heated leading edge structure (14) of any one of the preceding claims, further comprising an adhesive layer (28), the indirect heating device (44) being connected to the reinforcement member (22) by the adhesive layer (28).

8. A heated leading edge structure (14) according to any one of the preceding claims, wherein The heating apparatus (24) further comprises at least one direct heating device (46) mounted on the inner surface (34) of the leading edge panel (20).

9. A heated leading edge structure (14) according to any one of the preceding claims, wherein The heating device (24) further comprises: at least one temperature sensor (48); and a control unit (50), the control unit (50) being connected to the at least one temperature sensor (48), the control unit (50) comprising: an acquisition module (56) configured to acquire temperature information (Ta) from the at least one temperature sensor (48), and A control module (58) is configured to control at least one of the indirect heating devices (44) according to the collected temperature information (Ta).

10. A heated leading edge structure (14) according to claim 9 when appended to claim 8, wherein The control module (58) is further configured to control at least one of the direct heating devices (46) according to the collected temperature information (Ta).

11. The heated leading edge structure (14) of claim 10, wherein: The heating device (24) includes a plurality of temperature sensors (48), and the control module (58) is configured to control the direct heating device (46) or the indirect heating device (44) independently of at least one of the other.

12. The heated leading edge structure (14) according to any one of claims 9 to 11, wherein The temperature sensor (48): configured to measure the temperature (Tm) of one of the heating devices (44, 46), or configured to measure the temperature (Tm) of the inner surface (34) of the leading edge panel (20), or Configured to measure an ambient temperature (Tm) in a cavity (C) defined by the inner surface (34) of the leading edge panel (20).

13. A slat (18) comprising a heated leading edge structure (14) according to any one of claims 1 to 12.

14. A wing (12) comprising a heated leading edge structure (14) according to any one of claims 1 to 12 and / or a slat (18) according to claim 13.

15. An aircraft (10) comprising a heated leading edge structure (14) according to any one of claims 1 to 12 and / or a slat (18) according to claim 13 and / or a wing (12) according to claim 14.

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