Patent Application
20200331616
The present disclosure relates to leading edges on aircrafts, and more particularly, to bonded structural ribs for heating a leading edge of an aircraft.
Aircrafts are equipped with wings, which generate lift and enable aircrafts to fly. Ice accretion may occur on a leading edge of an aircraft due to cold temperatures at high altitudes. A leading edge may be heated by utilizing thermoelectric heaters along a leading edge of an aircraft. A structural rib may be added in spaced increments to a leading edge to provide support to the leading edge. There is a need in the art to have a continuous thermoelectric heater across a leading edge, where the structural ribs do not interrupt the thermoelectric heater.
An aircraft is disclosed herein. The aircraft may comprise a fuselage, a wing, a thermoelectric element, a first chemical adhesive, a second chemical adhesive, and a first structural rib. The wing may have a leading edge, a suction side portion, a pressure side portion, and a wing tip. The thermoelectric element may have a thermoelectric inner surface extending from a first end of the leading edge in a spanwise direction to a second end of the leading edge. The first end being proximate the fuselage and the second end being proximate the wing tip. The first chemical adhesive may be disposed between a leading edge inner surface of the leading edge and the thermoelectric element. The second chemical adhesive may be disposed on the thermoelectric inner surface. The first structural rib may be disposed on the second chemical adhesive.
In various embodiments, the first structural rib may comprise a forward flange having a rounded shape and a radial flange extending radially inward from a forward flange inner surface of the forward flange. The radial flange may have a plurality of apertures disposed circumferentially around the radial flange and extending in the spanwise direction through the radial flange. The aircraft may further comprise a grommet disposed in an aperture from the plurality of apertures. The aircraft may further comprise a first wire and a second wire, the first wire and the second wire being supported by the grommet. The aircraft may further comprise a second structural rib disposed on the thermoelectric element between the wing tip and the first structural rib. The first wire may extend to a connection point between the first structural rib and the second structural rib, and the second wire may extend to a connection point between the second structural rib and the wing tip. The first structural rib may further comprise a bottom flange extending in a chordwise direction from a bottom surface of the forward flange and a top flange extending in the chordwise direction from a top surface of the top flange. The first structural rib may further comprise a vertical support extending from the top flange to the bottom flange. The first structural rib may further comprise a first rivet aperture disposed on the bottom flange and a second rivet aperture disposed on the top flange. The aircraft may further comprise a first rivet coupling the bottom flange to the suction side portion via the first rivet aperture, and a second rivet coupling the top flange to the pressure side portion via the second rivet aperture.
A wing is disclosed herein. The wing may comprise a leading edge, a thermoelectric element, a chemical adhesive, and a structural rib. The leading edge may have a leading edge inner surface. The thermoelectric element may be disposed on the leading edge inner surface. The thermoelectric element may have a thermoelectric inner surface. The chemical adhesive may be disposed on a portion of the thermoelectric inner surface. The structural rib may be coupled to the chemical adhesive. The structural rib may comprise a forward flange, a bottom flange, and a top flange. The forward flange may have a contoured outer surface, the contoured outer surface being complimentary to the thermoelectric inner surface and interfacing with the chemical adhesive. The bottom flange may extend in a chordwise direction from a bottom surface of the forward flange toward a trailing edge of the wing. The bottom flange may have a first rivet aperture. The top flange may extend in the chordwise direction from a top surface of the forward flange toward the trailing edge of the wing. The top flange may have a top rivet aperture.
In various embodiments, the structural rib may further comprise a vertical support extending from the bottom flange to the top flange. The forward flange may further comprise a radial flange extending radially inward from a forward flange inner surface of the forward flange, the radial flange having a plurality of apertures extending axially through the radial flange. The wing may further comprise a grommet disposed within an aperture from the plurality of apertures. The wing may further comprise a first wire and a second wire, the first wire and the second wire being supported by the grommet.
A method for coupling a structural rib and a thermoelectric element to a leading edge of a wing is disclosed herein. The method may comprise disposing a second chemical adhesive on a portion of an inner surface of the thermoelectric element; disposing the thermoelectric element on a leading edge inner surface of the leading edge; disposing the structural rib on the thermoelectric element, the structural rib having a forward flange, the forward flange having a contoured surface being complimentary to the leading edge, the contoured surface being in contact with the second chemical adhesive; and curing the second chemical adhesive.
In various embodiments, the method may further comprise fastening the structural rib to a suction side of the wing and fastening the structural rib to a pressure side of the wing. The structural rib may be electrically isolated from the thermoelectric element. The method may further comprise disposing a first chemical adhesive on an outer surface of the thermoelectric element as a first step, wherein disposing the thermoelectric element may further comprise having the inner surface of the leading edge in contact with the first chemical adhesive. The curing of the second chemical adhesive may further comprise curing the first chemical adhesive.
The subject matter of the present disclosure is particularly pointed out and distinctly claimed in the concluding portion of the specification. A more complete understanding of the present disclosure, however, may best be obtained by referring to the detailed description and claims when considered in connection with the following illustrative figures. In the following figures, like reference numbers refer to similar elements and steps throughout the figures.
Elements and steps in the figures are illustrated for simplicity and clarity and have not necessarily been rendered according to any particular sequence. For example, steps that may be performed concurrently or in different order are illustrated in the figures to help to improve understanding of embodiments of the present disclosure.
The detailed description of exemplary embodiments herein makes reference to the accompanying drawings, which show exemplary embodiments by way of illustration. While these exemplary embodiments are described in sufficient detail to enable those skilled in the art to practice the disclosures, it should be understood that other embodiments may be realized and that logical changes and adaptations in design and construction may be made in accordance with this disclosure and the teachings herein. Thus, the detailed description herein is presented for purposes of illustration only and not of limitation.
The scope of the disclosure is defined by the appended claims and their legal equivalents rather than by merely the examples described. For example, the steps recited in any of the method or process descriptions may be executed in any order and are not necessarily limited to the order presented. Furthermore, any reference to singular includes plural embodiments, and any reference to more than one component or step may include a singular embodiment or step. Also, any reference to tacked, attached, fixed, coupled, connected or the like may include permanent, removable, temporary, partial, full and/or any other possible attachment option. Additionally, any reference to without contact (or similar phrases) may also include reduced contact or minimal contact.
Disclosed herein is a leading-edge heating system designed to provide uniform heat to the leading edge of an aircraft, while maintaining the structural integrity of the wing.
A leading-edge heating system, as disclosed herein, may have particular application for de-icing a leading edge of a wing upon ice accretion forming during flight. A leading-edge heating system, as disclosed herein, may have a continuous electrothermal heater extending continuously across the span of a leading edge, and the system may use a plurality of structural ribs spaced across the span of the leading-edge. The leading edge heating system may bond the continuous electrothermal heater to a leading edge skin disposed on an internal surface of a wing. The plurality of structural ribs may be bonded to the electrothermal heater via adhesive bonding.
With reference to
Referring now to
In various embodiments, bottom flange 210 may comprise a bottom rivet aperture 212. The bottom rivet aperture 212 may extend through flange 210 from a bottom flange top surface to a bottom flange bottom surface. Similarly, top flange 220 may comprise top rivet apertures (222, 224, 226). Top rivet apertures (222, 224, 226) may extend through a top flange top surface to a top flange bottom surface. The bottom rivet aperture 212 and the top rivet apertures (222, 224, 226) may be configured to receive rivets to mechanically fasten the structural rib to an aircraft wing. The top flange 220 and the bottom flange 210 may be disposed aft of the forward flange 240. By being aft the forward flange 240, mechanically fastening bottom flange 210 and top flange 220 to an aircraft wing may not disrupt a thermoelectric heating element disposed along a leading edge of an aircraft. In various embodiments, forward flange 240 is a continuous surface extending from an edge of top flange 220 along a radius of curvature to an edge of the bottom flange 210 creating a rounded forward flange 240.
In various embodiments, the structural rib 200 may be manufactured from composite materials, aluminum, titanium, stainless steel, or any other material commonly known in the art. In various embodiments, the structural rib 200 is manufactured from carbon fiber, fiberglass, Amarid, thermoplastic fibers (e.g., polypropylene, polyester, polyethylene, metallic composite hybrids (e.g., fiberglass/aluminum)). In various embodiments, materials could be woven or non-woven including unidirectional plain satins, twill, spread tow, etc. In various embodiments, composite materials can be impregnated with resins, such as epoxy, cyanate ester, bismaleimides, polyester, phenolic, polyimide, and/or benzoxazines.
Referring now to
In various embodiments, a first chemical adhesive 330 may be disposed between the thermoelectric element 320 and the and the leading edge portion 312 of the wing skin 310. Similarly, a second chemical adhesive 340 may be disposed between the forward flange 240 and the thermoelectric element 320. In various embodiments, composite material of the structural rib 200 can be impregnated with the first chemical adhesive 330, such as epoxy, cyanate ester, bismaleimides, polyester, phenolic, polyimide, and/or benzoxazines. In various embodiments, the first chemical adhesive 330 may comprise epoxy. In various embodiments, the second chemical adhesive 340 may be similar, or dissimilar, to the first chemical adhesive 330. In various embodiments, thermoelectric element 320 may be adhesively bonded to the leading edge portion 312 of the wing skin 310. Similarly, the structural rib 200 may be adhesively bonded to the thermoelectric element along an outer surface of forward flange 240. The chemical adhesives (330, 340) may electrically isolate the thermoelectric element 320 from the wing skin 310 and the structural rib 200. This may prevent the thermoelectric element 320 from short circuiting and enable the thermoelectric element 320 to provide uniform heating to the leading edge portion 312 of the wing skin 310. In various embodiments, the chemical adhesives (330, 340) may bond the components together without the addition of heat and/or thermal treatment.
In various embodiments, the structural rib 200 may be mechanically fastened to the wing skin 310 aft of the leading edge portion 312. By mechanically fastening the structural rib back into the suction side 311 and the pressure side 313 of the structural rib may be tied back into the larger ribs within the airfoil structure, creating a more robust structural rib for support of the leading edge. In various embodiments, the structural rib 200 may be mechanically fastened to the pressure side 313 of the wing via a pressure side rivet 350. In various embodiments, a plurality of suction side rivets (352, 354, 356) may fasten the structural rib to the suction side 311 of the wing. A single pressure side rivet 313 may limit the interruption of the lifting surface. In various embodiments, the rivets (350, 352, 354, 356) may be electrically isolated from the thermoelectric heater via chemical adhesives (330, 340). Additionally, by mechanically fastening the structural rib 200, in addition to the adhesive bonding, the structural rib may continue to provide structural support to the leading edge portion 312 if the adhesive bond were to break.
Referring now to
In various embodiments, the structural rib 400 may be manufactured from composite materials, aluminum, titanium, stainless steel, or any other suitable material commonly known in the art. In various embodiments, the structural rib 200 is manufactured from carbon fiber, fiberglass, Amarid, thermoplastic fibers (e.g., polypropylene, polyester, polyethylene, metallic composite hybrids (e.g., fiberglass/aluminum). In various embodiments, materials could be woven or non-woven including unidirectional plain satins, twill, spread tow, etc. In various embodiments, composite materials can be impregnated with resins, such as epoxy, cyanate ester, bismaleimides, polyester, phenolic, polyimide, and/or benzoxazines.
Referring now to
In various embodiments, a first chemical adhesive 330 may be disposed between the thermoelectric element 320 and the and the leading edge portion 312 of the wing skin 310. Similarly, a second chemical adhesive 340 may be disposed between the forward flange 440 and the thermoelectric element 320. In various embodiments, thermoelectric element 320 may be adhesively bonded to the leading edge portion 312 of the wing skin 310. Similarly, the structural rib 400 may be adhesively bonded to the thermoelectric element along an outer surface of forward flange 440. The chemical adhesives (330, 340) may electrically isolate the thermoelectric element 320 from the wing skin 310 and the structural rib 400. This may prevent the thermoelectric element 320 from short circuiting and enable the thermoelectric element 320 to provide uniform heating to the leading edge portion 312 of the wing skin 310.
Referring now to
With reference to
In various embodiments, the first structural rib 601 may be proximate the fuselage. In various embodiments, the distance between the first structural rib 601 and the second structural rib 602 may be greater than the distance between the second structural rib 602 and the third structural rib 603. In various embodiments, the thermoelectric element 320 may provide more uniform heat distribution and use less power than if the electrical circuits were stopped between structural ribs because the heating areas between ribs may differ. In various embodiments, the first connection point 611 and the second connection point 621 may be more precisely located and/or enable a continuous thermoelectric element 320 across the span of a leading edge of an airfoil.
In various embodiments, the outer surface 322 of the thermoelectric element 320 may be coupled to a leading edge inner surface 314 disposed radially inward of the leading edge outer surface via the first chemical adhesive 330 (step 715). In various embodiments, an outer surface of forward flange (240, 440) of structural rib (200, 400) may be disposed on the inner surface 324 of the thermoelectric element 320 (step 720).
In various embodiments, the first chemical adhesive 330 and the second chemical adhesive 340 may be cured at the same time by any method commonly known in the art. (step 725) In various embodiments, the first adhesive material may be cured prior to disposing the second chemical adhesive 340 on the thermoelectric element, and the second chemical adhesive 340 may be cured after the structural rib (200, 400) is disposed on the thermoelectric element 320. The first chemical adhesive 330 and the second chemical adhesive 340 may be cured at the same temperature for the same duration. In various embodiments, the first chemical adhesive 330 and the second chemical adhesive may be cured at different temperatures for different durations. In various embodiments, composite material of the structural rib 400 can be impregnated with the first chemical adhesive 330, such as epoxy, cyanate ester, bismaleimides, polyester, phenolic, polyimide, and/or benzoxazines.
In various embodiments the method 700 may further comprise fastening the structural rib 200 to the wing skin 310 (step 730). The fastening may be done aft of the leading edge portion 312. In various embodiments, the rivets (350, 352, 354, 356) may be electrically isolated from the thermoelectric element 320 by the first chemical adhesive 330 and/or the second chemical adhesive 340. The fastening may be done by method known in the art, such via rivets, bolts, screws, or the like.
Benefits, other advantages, and solutions to problems have been described herein with regard to specific embodiments. Furthermore, the connecting lines shown in the various figures contained herein are intended to represent exemplary functional relationships and/or physical couplings between the various elements. It should be noted that many alternative or additional functional relationships or physical connections may be present in a practical system. However, the benefits, advantages, solutions to problems, and any elements that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as critical, required, or essential features or elements of the disclosures. The scope of the disclosures is accordingly to be limited by nothing other than the appended claims and their legal equivalents, in which reference to an element in the singular is not intended to mean “one and only one” unless explicitly so stated, but rather “one or more.” Moreover, where a phrase similar to “at least one of A, B, or C” is used in the claims, it is intended that the phrase be interpreted to mean that A alone may be present in an embodiment, B alone may be present in an embodiment, C alone may be present in an embodiment, or that any combination of the elements A, B and C may be present in a single embodiment; for example, A and B, A and C, B and C, or A and B and C.
Systems, methods and apparatus are provided herein. In the detailed description herein, references to “various embodiments”, “one embodiment”, “an embodiment”, “an example embodiment”, etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described. After reading the description, it will be apparent to one skilled in the relevant art(s) how to implement the disclosure in alternative embodiments.
Furthermore, no element, component, or method step in the present disclosure is intended to be dedicated to the public regardless of whether the element, component, or method step is explicitly recited in the claims. No claim element is intended to invoke 35 U.S.C. 112(f), unless the element is expressly recited using the phrase “means for.” As used herein, the terms “comprises”, “comprising”, or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
