An electrically heated anti-icing and de-icing wing skin structure and its molding method

Abstract

This invention provides an electrically heated anti-icing and de-icing wing skin structure and its molding method. The wing skin structure includes a leading edge skin and a heating element integrally formed with the leading edge skin and arranged inside it. The heating element includes a heating wire film and an electrode patch. The heating wire film has a thin-layer structure, consisting of an insulating layer, a heating wire layer, and an insulating layer in sequence. At least one side of the heating wire layer has a heat-conducting layer. The inner end face of the electrode patch is connected to the heating wire film, and the outer end face extends through the inner surface of the leading edge skin and is connected to a power supply cable. The leading edge skin is installed on the leading edge of the wing. This invention integrally molds the heating element with the wing skin. The heating element is close to the outer surface of the wing skin, which facilitates heat transfer and reduces secondary arrangement and installation operations. It optimizes the heat conduction method and electrical connection method of the heating element, resulting in a simple structure and improved de-icing efficiency and structural reliability.

Description

Technical Field

[0001] This invention relates to the field of wing de-icing technology, and in particular to an electrically heated de-icing wing skin structure and its molding method. Background Technology

[0002] During flight at high altitudes, the low temperatures and supercooled water droplets in clouds cause icing to form on the leading edges of the wings. This icing severely impedes airflow, and in severe cases, alters the pressure difference between the upper and lower surfaces of the wing, affecting flight performance. Therefore, it is necessary to design an anti-icing and de-icing system for the wings to remove icing from the affected areas.

[0003] Currently, the main de-icing methods include mechanical de-icing, electrothermal de-icing, and hot gas de-icing. Mechanical de-icing has a complex structure and significantly affects the aerodynamic shape of the wing itself. Hot gas de-icing also suffers from structural complexity; piping connections increase structural weight, and de-icing efficiency is low. Traditional electrothermal de-icing methods often involve attaching heating elements to the inner surface of the wing skin to heat and de-ic the skin. This method suffers from low heating efficiency, slow heat conduction, and high energy consumption, and the installation of heating elements on the inner surface of the skin is cumbersome.

[0004] Therefore, there is a need for an anti-icing and de-icing structure that is highly efficient, energy-saving, and easy to deploy. Summary of the Invention

[0005] To address the technical problems of low efficiency, high energy consumption, and complex arrangement of heating elements in existing wing de-icing technologies, this invention provides an electrically heated de-icing wing skin structure and its forming method. The heating element is integrally formed with the wing skin, and the heating element is arranged inside the wing skin, close to the outer surface of the skin. A heat-conducting layer is added to increase the heat conduction area. This de-icing wing skin structure has high de-icing efficiency, low energy consumption, and excellent de-icing performance, while avoiding the need for secondary installation of heating elements.

[0006] The technical solution adopted by the present invention to solve the above problems is as follows:

[0007] This invention provides an electrically heated anti-icing and de-icing wing skin structure, including a leading edge skin and a heating element disposed within the leading edge skin and integrally formed with the leading edge skin; the heating element includes a heating wire film and an electrode patch; the heating wire film has a thin-layer structure, comprising an insulating layer, a heating wire layer, and an insulating layer in sequence, and the heating wire layer has a heat-conducting layer on at least one side; the inner end face of the electrode patch is connected to the heating wire film, and the outer end face extends through the inner surface of the leading edge skin and is connected to a power supply cable.

[0008] Furthermore, the electrode patch has a multi-layered stepped structure, with a large inner end face area connected to the heating wire film and a small outer end face area connected to the power supply cable.

[0009] Furthermore, the electrode patch is divided into positive and negative electrodes, which are used to connect to the positive and negative electrodes of the heating wire film, respectively.

[0010] Furthermore, the heating element is a multi-piece structure arranged in sections within the leading edge skin.

[0011] Furthermore, a heat-conducting layer is provided on both sides of the heating wire layer, and the heat-conducting layer is a copper foil sheet; an adhesive film layer is also laid on the contact surface of the heating wire film, the electrode patch and the leading edge skin.

[0012] Furthermore, the wing skin structure also includes an upper skin and a lower skin, the upper and lower skins being fixed to the wing frame, and the leading edge skin being fixed to the upper and lower skins.

[0013] Furthermore, several temperature sensors and icing sensors are arranged on the inner side of the connection between the leading edge skin and the upper and lower skins, and a control unit and a heating power supply are arranged on the inner side of the fuselage;

[0014] The icing sensor is used to detect the icing area and degree of icing on the outer surface of the wing skin and transmit the data to the control unit.

[0015] The temperature sensor is used to detect the temperature of the wing skin and transmit the data to the control unit;

[0016] The control unit controls the heating element to heat the icing area based on the detection results of the icing sensor, and adjusts the temperature of the heating element based on the detection results of the temperature sensor.

[0017] The heating power supply is used to power the heating element and shares power with other equipment on the machine.

[0018] Furthermore, the icing sensor and temperature sensor operate in an intermittent manner; the control unit controls the heating element to preheat the skin at low temperatures, so that the skin temperature is higher than the freezing point.

[0019] The present invention also provides a method for forming an electrically heated anti-icing wing skin structure, comprising the following steps:

[0020] Preparation of heating wire thin film;

[0021] Several layers of fiber cloth and one layer of adhesive film are laid in the mold. The heating wire film and electrode patches are arranged in sections on the adhesive film according to the position requirements.

[0022] After the laying is completed, an adhesive film layer is laid on the surface of the heating wire film and electrode patch, and the pretreated fiber cloth is laid on the heating wire film and electrode patch to complete the laying.

[0023] After the skin is laid, it is placed in an autoclave or vacuum curing oven to complete the curing and shaping of the wing leading edge skin.

[0024] Furthermore, the molding method also includes sandblasting the surface of the heating wire film and electrode patch before laying; after the leading edge skin is cured and molded, the surface of the electrode patch is cleaned and the power supply cable is connected.

[0025] The beneficial effects of this invention are:

[0026] This invention provides an electrically heated anti-icing and de-icing wing skin structure and its molding method, which has the following advantages:

[0027] (1) The heating element is set between the fiber cloth of the wing skin. The heating element is a thin film heating wire. The heating element is thin, lightweight and conforms well. It will not affect the structural performance of the skin under normal conditions and under heating conditions.

[0028] (2) The power supply interface of the heating element adopts an electrode patch structure, with the heating wire film embedded inside the fiber layer. The power supply interface is located on the inner surface of the skin and directly connected to the outside. On the one hand, this solves the problem of connecting the power supply cable to the internal heating element during the molding process, preventing damage to the power supply cable due to improper operation in traditional molding processes, improving the success rate of the product, simplifying the operation difficulty during molding, and avoiding processes such as reserving cable passage holes. On the other hand, in the use of traditional electric heating anti-icing structures, once the power supply cable is damaged, it is difficult to connect a new cable to the power supply interface, and the wing will lose its anti-icing function. However, in this invention, if the connecting cable is damaged, the power supply cable can be maintained by welding or adding a new one, improving the reliability and maintainability of the system.

[0029] (3) The internal space of the leading edge of the wing of a high-speed UAV is small, making the installation and arrangement of the heating element difficult. Using connectors for fixation would increase the weight of the entire aircraft. In this invention, the heating element is integrally formed with the wing skin, and the heating element is embedded between the layers of fiber cloth. This results in a better overall effect, avoids the need for secondary fixing of the heating element on the inner surface of the skin, simplifies the process, reduces the difficulty of operation, and improves the reliability of the system.

[0030] (4) Heating elements generally consume relatively large amounts of power and energy during operation. The heating element of this invention is located close to the outer surface of the skin, near the icing zone, shortening the heat conduction path and enabling rapid heat transfer. Simultaneously, heat-conducting layers are placed on both sides of the heating wire, improving heat conduction efficiency. This is of great significance for reducing energy consumption, rapid de-icing, ensuring flight safety, and increasing the overall flight time. Furthermore, the zoned arrangement of the heating elements allows for individual heating control of the heating elements in each area, effectively reducing overall energy consumption and significantly improving the aircraft's flight time.

[0031] (5) The heating element can preheat the skin at low temperatures, so that the skin temperature is higher than the freezing point, thus avoiding freezing problems. Attached Figure Description

[0032] The accompanying drawings, which form part of this specification, are provided to further illustrate embodiments of the invention and, together with the textual description, explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0033] Figure 1 A schematic diagram of an electrically heated anti-icing and de-icing wing skin structure provided for a specific embodiment of the present invention;

[0034] Figure 2 A schematic diagram of a heating element and a leading edge skin layup structure provided for a specific embodiment of the present invention;

[0035] Figure 3 A schematic diagram illustrating the arrangement of a heating element and a leading edge skin, provided for a specific embodiment of the present invention;

[0036] Figure 4 This is a control principle diagram of an electrically heated anti-icing and de-icing wing skin structure provided for a specific embodiment of the present invention.

[0037] The accompanying drawings include the following reference numerals:

[0038] 1. Heating element; 1-1. Heating wire film; 1-2. Electrode patch; 2-1. Leading edge skin; 2-2. Upper skin; 2-3. Lower skin; 3. Temperature sensor; 4. Icing sensor; 5. Control unit; 6. Heating power supply. Detailed Implementation

[0039] The technical solution of the present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0040] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of components and steps set forth in these embodiments do not limit the scope of the invention.

[0041] This invention provides an electrically heated anti-icing and de-icing wing skin structure, including a leading edge skin and a heating element 2-1 integrally formed with the leading edge skin. The heating element 1 includes a heating wire film 1-1 and an electrode patch 1-2. The heating wire film has a thin-layer structure, which includes an insulating layer, a heating wire layer, and an insulating layer in sequence. At least one side of the heating wire layer is provided with a heat-conducting layer. The inner end face of the electrode patch is connected to the heating wire film, and the outer end face extends through the inner surface of the leading edge skin and is connected to a power supply cable. The leading edge skin is installed on the leading edge of the wing and conforms to the shape of the wing structure.

[0042] This invention integrates the heating element with the wing skin, positioning the heating element inside the wing skin near its outer surface. An additional heat-conducting layer increases the heat-conducting area, improving de-icing efficiency and reducing energy consumption, while eliminating the need for secondary installation of the heating element. Electrode patches are used for electrical connection, enhancing reliability and maintainability. This wing skin structure exhibits excellent de-icing performance.

[0043] The technical solution of the present invention will be described in detail below with reference to a specific embodiment.

[0044] like Figure 1 As shown, an electrically heated anti-icing wing skin structure mainly includes a composite material skin and a heating element 1. The composite material skin includes an upper skin 2-2, a lower skin 2-3, and a leading edge skin 2-1. The leading edge skin 2-1 is formed by laying multiple layers of fiber layers and adhesive film layers. The heating element 1 is arranged inside the leading edge skin 2-1, near the outer surface of the leading edge skin. The upper and lower skins are fixed to the wing frame by bonding and riveting, and the leading edge skin 2-1 is connected to the upper and lower skins by bonding. An icing sensor 4 and a temperature sensor 3 are also arranged inside the wing skin structure. In addition, a control unit 5 and a heating power supply 6 are arranged inside the fuselage.

[0045] Heating element 1 is mainly used to heat the surface of the skin. The temperature of the outer surface of the skin is higher than the freezing point temperature, so as to melt the ice layer on the surface and achieve the purpose of preventing and removing ice. In this invention, the heating element and the leading edge skin are integrally laid and formed, and after the skin is cured, the heating element and the skin are a whole.

[0046] like Figure 2 As shown, the heating element 1 includes a heating wire film 1-1 and an electrode patch 1-2.

[0047] The heating wire film 1-1 has a thin-layer structure, comprising, in sequence, an insulating layer, a heat-conducting layer, a heating wire layer, another heat-conducting layer, and an insulating layer. The heating wires in the heating wire layer are uniformly distributed between two heat-conducting layers (such as copper foil), serving as the main heating element. The heat-conducting layers are disposed on both sides of the heating wire layer to increase the heat-conducting area, improve de-icing efficiency, ensure heat uniformity, and avoid localized heating. In other embodiments, the heat-conducting layer may be disposed only on the side closest to the outer surface of the skin. The insulating layer provides insulation between the heating wire film 1-1 and the leading edge skin.

[0048] Electrode patches 1-2 include positive and negative electrodes, which are respectively connected to the positive and negative electrodes of the heating wire in the heating wire film. The inner end face of the electrode patch is connected to one end of the heating wire in the heating wire film, and the outer end face extends through the inner surface of the leading edge skin and is connected to the power supply cable of the heating power source, thereby connecting the heating element inside the skin to the power supply cable of the UAV power system. Preferably, the electrode patch adopts a multi-layer stepped structure, with a large area on the inner end face connected to the heating wire film and a small area on the outer end face connected to the power supply cable, such as... Figure 2 As shown, the heating element is formed by machining, and its surface curvature is consistent with that of the wing's outer surface. During the integral forming process of the heating element and the leading edge skin, part of the fiber layer of the leading edge skin is laid on part of the steps of the electrode patch, pressing the electrode patch tightly inside the leading edge skin, increasing strength, and preventing the electrode patch from falling off. Preferably, the width of the edge of a single step is not less than 5mm to facilitate the overlap of the fiber cloth.

[0049] Preferably, the heating elements are arranged in a multi-piece, zoned manner, such as... Figure 3 As shown, by arranging the heating elements according to the icing area, multiple heating elements can be heated and controlled separately, which improves the anti-icing and de-icing efficiency, reduces the overall energy consumption of the aircraft, and has a significant effect on improving the endurance of the aircraft.

[0050] Multiple icing sensors 4 and temperature sensors 3 are arranged according to the monitoring needs of the icing area or heating element, located on the inner side of the bonding area between the leading edge skin 2-1 and the upper and lower skins. Icing sensor 4 is mainly used to detect the icing area and degree of icing on the outer surface of the wing's leading edge. When the icing sensor detects icing on the outer surface of the skin (the icing detector operates on the principle of acoustic wave detection, responding to the sound waves reflected back after the object passes through it; in the absence of ice, the amplitude of the echo emitted by the sensor is constant; when the skin surface is icy, the echo amplitude signal changes; the change in amplitude signal varies depending on the thickness of the ice layer, thus determining whether the surface is icy and the thickness of the ice layer), the icing sensor transmits the signal to the control unit in the form of an electrical signal. The control unit then controls the heating element to heat the icing area and melt the ice. The temperature sensor is mainly used to detect the temperature of the skin surface, monitor the heating temperature of the heating element, and transmit the temperature data to the control unit to prevent excessively high temperatures in the heating area from damaging the skin structure.

[0051] The control unit 5 is mainly used to collect data from the icing sensor 4 and the temperature sensor 3, and to control the operation of the heating elements. Multiple heating elements are connected to the control unit 5 via cables, and each heating element can be controlled individually. The control unit 5 can also control the heating elements to preheat the skin at low temperatures, ensuring that the skin temperature is above the freezing point and preventing icing problems.

[0052] like Figure 4 As shown, when the icing sensor 4 detects an icing area and degree of icing on the outer surface of the wing leading edge 2-1, it transmits the signal to the control unit 5 in the form of an electrical signal. The control unit 5 then controls the heating element 1 to heat the icing area. Simultaneously, the temperature sensor 3 monitors the skin temperature of the heated area and feeds the temperature back to the control unit 5, which then adjusts the temperature of the heating element 1 again. When the temperature sensor 3 detects that the skin temperature has reached the set value, the control unit 5 maintains the temperature of the heating element 1 unchanged. This adjustment process continues until the ice layer in the icing area completely melts and is carried away by the airflow. At this point, the icing sensor 4 sends a no-icing signal to the control unit 5, and the control unit 5 stops the heating element 1 from heating. The heating power supply 6 is mainly used to power the heating element and shares a power supply with other equipment on the aircraft.

[0053] Preferably, to reduce energy consumption, the icing and temperature sensors operate intermittently. Based on flight altitude and atmospheric conditions, control unit 5 controls whether the icing sensor is activated, and then determines the degree of icing. Based on the operating status of the heating element, control unit 5 controls whether the temperature sensor is activated to monitor the skin temperature.

[0054] The electric heating anti-icing and de-icing wing skin structure provided by this invention features a heating element integrally formed with the wing skin, positioned close to the outer surface of the wing skin for easy heat transfer and to reduce secondary installation operations. This electric heating anti-icing and de-icing structure is simple in form, highly effective, and highly reliable.

[0055] The present invention also provides a method for integrally molding the heating element and the leading edge skin of the wing, specifically including the following steps:

[0056] S1. Prepare the heating wire film and perform sandblasting treatment on the surface of the heating wire film and electrode patch;

[0057] The heating wire film is laid out in a mold in the order of insulation layer, heat-conducting layer, heating wire layer, heat-conducting layer, and insulation layer, ensuring that both ends of the heating wire extend out. After laying, it is placed in an autoclave or vacuum curing oven for curing and shaping. Then, the surfaces of the heating wire film and electrode patches are sandblasted to increase the surface roughness of the film and electrode patches and improve the interlayer adhesion with the fiber cloth.

[0058] S2. Lay several layers of fiber cloth and adhesive film in the mold, and arrange the heating wire film and electrode patches in sections on the adhesive film according to the position requirements.

[0059] To bring the heating wire film close to the outer surface of the leading edge skin, preferably, two layers of fiber cloth can be laid.

[0060] Electrode patches are pressed onto the positive and negative ends of the heating wire according to their polarity.

[0061] S3. After laying, lay an adhesive film layer on the surface of the heating element, and lay the pre-treated fiber cloth on the heating element to complete the laying.

[0062] The fiber cloth is pre-treated, and an electrode patch outlet is reserved at the corresponding electrode patch location on the fiber cloth. The number of fiber cloth layers is designed according to the skin strength.

[0063] S4. After the skin is laid, it is placed in an autoclave or vacuum curing oven to complete the curing and shaping of the wing leading edge skin.

[0064] S5. Clean the surface of the electrode patch and connect the power supply cable.

[0065] After the leading edge skin has been cured and molded, the electrode patches need to be processed. The adhesive layer on the surface of the electrode patches during the skin molding process is cleaned, and cables are welded to the surface of the electrode patches to connect to the heating power supply of the UAV.

[0066] In this invention, the heating element and the leading edge skin of the wing are integrally formed. Adhesive film layers are added to both sides of the heating wire film, and these adhesive film layers are connected to the inner surface of the electrode patches. The adhesive film layers increase the overall strength and stability of the molding. The fiber layer at the electrode patches is laid in a multi-layered overlapping structure, with no fiber cloth laid at the topmost protrusion of the electrode patches, increasing the connection stability of the electrode patches. The heating element and the skin fiber cloth are integrally formed, and the electrode patches are located at the power supply interface of the heating wire film. The electrode patches are directly connected to the outside, solving the problem of difficult power supply interfaces for the heating element.

[0067] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0068] The parts of this invention not described in detail are techniques known to those skilled in the art.

Claims

1. An electrically heated anti-icing and de-icing wing skin structure, characterized in that, It includes a leading edge skin and a heating element disposed within the leading edge skin and integrally formed with the leading edge skin; the heating element includes a heating wire film and an electrode patch; the heating wire film has a thin layer structure, which includes an insulating layer, a heating wire layer, and an insulating layer in sequence; The inner end face of the electrode patch is connected to the heating wire film, and the outer end face extends through the inner surface of the leading edge skin and is connected to the power supply cable. The heating element is arranged inside the leading edge skin, near the outer surface of the leading edge skin; The electrode patch has a multi-layered stepped structure, with a large inner end face area connected to the heating wire film and a small outer end face area connected to the power supply cable. A heat-conducting layer is provided on both sides of the heating wire layer, and the heat-conducting layer is a copper foil sheet; an adhesive film layer is also laid on the contact surface between the heating wire film, the electrode patch and the leading edge skin. The wing skin structure also includes an upper skin and a lower skin, the upper and lower skins being fixed to the wing frame, and the leading edge skin being fixed to the upper and lower skins; Several temperature sensors and icing sensors are arranged on the inner side of the connection between the leading edge skin and the upper and lower skins. A control unit and a heating power supply are installed on the inner side of the fuselage. The icing sensors and temperature sensors operate in an intermittent mode. The heating wire film and electrode patch are sandblasted before being laid.

2. The electrically heated anti-icing and de-icing wing skin structure according to claim 1, characterized in that, The electrode patch is divided into positive and negative electrodes, which are used to connect to the positive and negative electrodes of the heating wire film, respectively.

3. The electrically heated anti-icing and de-icing wing skin structure according to claim 1, characterized in that, The heating element consists of multiple pieces, arranged in sections within the leading edge skin.

4. The electrically heated anti-icing and de-icing wing skin structure according to claim 1, characterized in that, The icing sensor is used to detect the icing area and degree of icing on the outer surface of the wing skin and transmit the data to the control unit. The temperature sensor is used to detect the temperature of the wing skin and transmit the data to the control unit; The control unit controls the heating element to heat the icing area based on the detection results of the icing sensor, and adjusts the temperature of the heating element based on the detection results of the temperature sensor. The heating power supply is used to power the heating element and shares power with other equipment on the machine.

5. The electrically heated anti-icing and de-icing wing skin structure according to claim 4, characterized in that, The control unit controls the heating element to preheat the skin at low temperatures, so that the skin temperature is above the freezing point.

6. A method for molding an electrically heated anti-icing and de-icing wing skin structure, characterized in that, The molding method for the electrically heated anti-icing and de-icing wing skin structure according to claims 1-5 includes the following steps: Preparation of heating wire thin film; Several layers of fiber cloth and one layer of adhesive film are laid in the mold. The heating wire film and electrode patches are arranged in sections on the adhesive film according to the position requirements. After the laying is completed, an adhesive film layer is laid on the surface of the heating wire film and electrode patch, and the pretreated fiber cloth is laid on the heating wire film and electrode patch to complete the laying. After the skin is laid, it is placed in an autoclave or vacuum curing oven to complete the curing and shaping of the wing leading edge skin.

7. The molding method for the electrically heated anti-icing and de-icing wing skin structure according to claim 6, characterized in that, The molding method further includes surface sandblasting treatment of the heating wire film and electrode patch before laying; After the leading edge skin is cured and formed, the surface of the electrode patch is cleaned and the power supply cable is connected.

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