Installation and implementation method of vortex generator modified part of large civil aircraft

Abstract

The invention provides a vortex generator modified part mounting method for a large civil aircraft, and belongs to the field of test flight verification of a flow control technology of the large civil aircraft. The method comprises the steps that 1, the specific structure and the installation position of the vortex generator are determined; 2, determining the structure of the modified part of the vortex generator; 3, a prefabricated body of the vortex generator modified part is manufactured on the ground; step 4, ensuring that the installation area is prepared; 5, marking the mounting position of the vortex generator modified part; step 6, fixing the vortex generator at a preset position by using a high-strength structural adhesive; step 7, cleaning the surface, and sealing the edge after the impregnating adhesive is completely cured; 8, after installation is completed, a flight test is conducted, and the improvement effect of the vortex generator on the lift coefficient and stall delay is evaluated. The structure and the mounting position of the vortex generator are optimally designed, so that the lift coefficient during aircraft landing is effectively improved, and stall is delayed.

Description

Technical Field

[0001] This invention relates to the aerospace field, particularly to the flight test and verification of flow control technology for large civil aircraft, and specifically to a method for installing a modified eddy current generator for a large civil aircraft. Background Technology

[0002] During landing, large civil aircraft often experience insufficient lift due to airflow separation and stall issues on the wing surface, affecting landing safety. Vortex generators, as simple and efficient passive flow control devices, can effectively delay flow separation, increase the wing's lift coefficient, and improve the aircraft's stall characteristics by inducing vortices to alter airflow.

[0003] Existing eddy current generators have been applied to various aircraft, but there is a lack of eddy current generator modification parts with sufficient strength, rigidity and surface hardness for application on large civil aircraft, as well as installation methods that can achieve rapid disassembly and assembly and improve flight test efficiency. Therefore, there is a lack of reliable test data to support this application. Summary of the Invention

[0004] The technical problem of this invention is to provide an installation method for a large civil aircraft vortex generator retrofit component. This method can install a vortex generator retrofit component with sufficient strength, rigidity and surface hardness on the aircraft through a simple and effective retrofit process.

[0005] The installation method mentioned includes the following steps:

[0006] Step 1: Based on the aerodynamic characteristics of the aircraft, determine the specific structure and installation location of the vortex generator;

[0007] Step 2: Determine the structure of the eddy current generator modification components according to the design requirements;

[0008] Step 3: Construct a prefabricated eddy current generator modification component on the ground;

[0009] Step 4: Clean and protect the installation location to ensure the installation area is ready.

[0010] Step 5: Use a positioning tool to mark the installation location of the eddy current generator modification part;

[0011] Step 6: Use high-strength structural adhesive to fix the eddy current generator in the predetermined position;

[0012] Step 7: Clean the surface and seal the edges after the impregnating adhesive has fully cured;

[0013] Step 8: After installation, conduct flight tests and evaluate the effect of the eddy current generator on improving lift coefficient and stall delay.

[0014] Optionally, in step 1, the vortex generator body is a fin-shaped lightweight structure designed to improve the wing root vortex system, improve the anti-separation ability, delay flow separation and enhance the lift. The aspect ratio, size and installation angle of the vortex generator are designed according to the aerodynamic characteristics of the aircraft wing, and the installation angle is generally 15° to 30°. The installation position of the vortex generator is the wing root of the wing, and it is specifically installed above the fairing of the wing.

[0015] Optionally, in step 2, the vortex generator modification piece adopts a composite sandwich structure, and the materials of each part are selected as follows:

[0016] 2.1, the main structure of the modification piece adopts 3D printing sandwich, which simulates the shape characteristics of the vortex generator;

[0017] 2.2, the inner and outer layers of the sandwich adopt a layer of 0.2mm glass fiber reinforced panel to improve the stiffness of the modification piece;

[0018] 2.3, the glass fiber reinforced panel wraps the sandwich to form a simulated vortex generator modification piece preform, which is made by using a ground mold to save installation time on the machine;

[0019] 2.4, the preform is pasted on the surface of the machine body to ensure the bonding strength.

[0020] Optionally, in step 3: the vortex generator modification piece preform is made in the following way:

[0021] 3.1, first evenly smear butter on the surface of the wing leading edge mold, then cover plastic film, and use a scraper to remove the bubbles inside the plastic film to make it have no obvious wrinkles;

[0022] 3.2, cooperate and fix the modification piece with the 3D printing mold;

[0023] 3.3, cut a piece of 0.2mm twill cloth according to the size of the outer surface of the modification piece;

[0024] 3.4, epoxy resin, benzene dimethylamine and dibutyl phthalate are configured into a glue solution with a mass ratio of 100:20:10, and are stirred uniformly;

[0025] 3.5, lay the 0.2mm twill cloth on the outer surface of the modification piece, dip the glue solution with a brush, and soak the twill cloth. During the operation, dip a small amount of glue solution with a brush each time to exclude bubbles;

[0026] 3.6, wipe the excess glue on the edge with alcohol;

[0027] 3.7, after 24 hours of curing time, take the preform out of the mold, tear off the inner surface plastic film, and use an angle grinder to appropriately trim the edge.

[0028] Optionally, in step 4: the 3M aluminum tape is overlapped and pasted along the spanwise direction on the surface of the installation area to protect the surface of the wing and meet the requirement of quick removal. The surface of the wing and the aluminum tape is cleaned with acetone before and after pasting the aluminum tape to ensure the pasting strength.

[0029] Optionally, in step 5: the prepared modification part is positioned and matched with the leading edge skin, and the distance between the modification part and the positioning point is measured to accurately position, and the pasting area of the inner surface of the modification part and the skin surface is drawn on the aluminum tape;

[0030] Optionally, in step 6: the structural adhesive is high-strength epoxy resin adhesive, A glue and B glue are prepared according to the proportion of 1:1, and then uniformly applied on the inner surface of the vortex generator modification part prefabricated body, the prefabricated body is installed according to the edge line on the skin, and the paper tape is used to fix the prefabricated body to prevent it from slipping due to gravity.

[0031] Optionally, in step 7: after the impregnated glue is completely cured, the edge is sealed with a metal tape.

[0032] Optionally, in step 8: after the installation is completed, flight test is carried out, and the effect of improving the lift coefficient and delaying the stall is verified by comparison with the vortex generator without installation.

[0033] Compared with the prior art, the vortex generator modification part provided by the present application has the advantages of:

[0034] The vortex generator modification part provided by the present application adopts a composite sandwich structure, has sufficient strength, rigidity and surface hardness, and the installation and implementation method is simple, fast and does not need to make large changes to the aircraft. Through reasonable vortex generator layout and accurate installation scheme, the lift coefficient of the aircraft can be significantly improved, and the stall can be delayed.

[0035] The present application optimizes the structure and installation position of the vortex generator to effectively improve the lift coefficient and delay the stall of the aircraft during landing. The modification part of the present application adopts a composite sandwich structure, combined with a simple installation process, without making large changes to the aircraft structure. The modification part has sufficient strength and surface hardness, and the aerodynamic performance of the modified aircraft is significantly improved, the stall angle of attack is delayed, the maximum lift is improved, and the flight safety is significantly enhanced. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 It is a schematic diagram of the vortex generator installed on the wing of a large civil aircraft.

[0037] Figure 2 It is a structural schematic diagram of the vortex generator, showing the shape, size and inclination angle of the vortex generator body.

[0038] Figure 3The structural schematic diagram for connecting the installation base of the vortex generator with the surface of the wing.

[0039] Figure 4 The schematic diagram for the implementation method of the vortex generator installation of the present application. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical scheme and effect of the present application more clear and explicit, the following examples are used to further explain the present application. It should be pointed out that the specific implementation described here is only used to explain the present application, and is not used to limit the present application.

[0041] Figure 1 The flow chart of the implementation method of the vortex generator retrofit part of the large civil aircraft of the embodiment of the present application. Referring to Figure 1 , the specific steps of the implementation method of the vortex generator retrofit part are as follows:

[0042] Step 1: According to the aerodynamic characteristics of the aircraft, the specific structure and installation position of the vortex generator are determined, Figure 2 The schematic diagram for the installation position and structure of the vortex generator.

[0043] In this embodiment, step 1: the vortex generator body is a fin-shaped lightweight structure, the aspect ratio, size and installation angle of which are referred to Figure 2 The installation position of the vortex generator is the wing root, and is specifically installed above the fairing of the wing.

[0044] Step 2: According to the design requirements, the structure of the vortex generator retrofit part is determined, Figure 3 The schematic diagram for the structure and installation of the vortex generator retrofit part.

[0045] In this embodiment, step 2: referring to Figure 3 , the vortex generator retrofit part adopts a composite sandwich structure, and the materials of each part are selected as follows:

[0046] 2.1, the main structure of the retrofit part adopts 3D printing sandwich, which simulates the shape characteristics of the vortex generator;

[0047] 2.2, the inner and outer surface layers of the sandwich adopt one layer of 0.2mm glass fiber reinforced panel, which improves the stiffness and strength of the retrofit part;

[0048] 2.3, the glass fiber reinforced panel wraps the sandwich to form a simulated vortex generator retrofit part preform, which is made by using a ground mold, thereby saving the installation time on the machine;

[0049] 2.4, the preform is pasted on the surface of the aircraft body to ensure the bonding strength.

[0050] Step 3: The preform of the vortex generator retrofit part is made on the ground.

[0051] In this embodiment, step 3: the vortex generator modification piece preform is made in the following way:

[0052] 3.1, first evenly apply butter on the surface of the wing leading edge mold, cover with plastic film, and use a scraper to remove the bubbles inside the plastic film to make it wrinkle-free;

[0053] 3.2, cooperate and fix the modification piece with the 3D printing mold;

[0054] 3.3, cut a piece of 0.2mm twill cloth according to the size of the outer surface of the modification piece;

[0055] 3.4, prepare the glue solution by mixing epoxy resin, benzene dimethylamine and dibutyl phthalate in a mass ratio of 100:20:10, and stir evenly;

[0056] 3.5, spread the 0.2mm twill cloth on the outer surface of the modification piece, and use a brush to dip the glue solution and soak the twill cloth. During the operation, dip a small amount of glue solution with the brush each time to remove the bubbles;

[0057] 3.6, wipe the excess glue solution on the edge with alcohol;

[0058] 3.7, after 24 hours of curing time, take the preform out of the mold, tear off the inner surface plastic film, and use an angle grinder to properly trim the edge.

[0059] Step 4: clean and protect the installation location to ensure that the installation area is ready.

[0060] In this embodiment, step 4: overlap and stick 3M aluminum tape on the surface of the installation area along the spanwise direction, and protect the wing surface to meet the requirement of quick removal. Clean the surface of the wing and aluminum tape with acetone before and after sticking the aluminum tape to ensure the sticking strength.

[0061] Step 5: use positioning tools to mark the installation position of the vortex generator modification piece.

[0062] In this embodiment, step 5: position the prepared modification piece with the leading edge skin, and measure the distance between the modification piece and the positioning point to accurately position it, and draw the sticking area of the inner surface of the modification piece and the skin surface on the aluminum tape.

[0063] Step 6: use high-strength structural adhesive to fix the vortex generator at the predetermined position.

[0064] In this embodiment, step 6: the structural adhesive is high-strength epoxy resin adhesive. After preparing the A and B adhesives in a ratio of 1:1, evenly apply them on the inner surface of the vortex generator modification piece preform, install the preform according to the edge line on the skin, and use paper tape to fix the preform to prevent it from slipping due to gravity.

[0065] Step 7: Clean the surface and seal the edges after the impregnation adhesive has fully cured.

[0066] In this embodiment, step 7: After the impregnating adhesive has completely cured, seal the edges with metal tape.

[0067] Step 8: After installation, conduct flight tests to verify and evaluate the performance improvement effect of the eddy current generator.

[0068] In this embodiment, step 8: After the installation is completed, a flight test is conducted and the effect of improving the lift coefficient and delaying stall is verified by comparing it with that of not installing the vortex generator. Figure 4 Comparison of flight test lift lines for the modified eddy current generator configuration and the basic configuration. (Reference) Figure 4 Two and five eddy current generators were added respectively for flight testing, and the lift lines of the flight tests were compared with those of the basic configuration.

[0069] Flight test results showed that the modified eddy current generator did not exhibit delamination or detachment, and possessed sufficient strength, rigidity, and surface hardness. The 2-blade and 5-blade eddy current generator configurations significantly improved the issues of premature stall and insufficient maximum lift in landing gear-down configurations: 2-blade eddy current generators delayed the stall angle of attack by 0.9° and increased maximum lift by 0.087°; 5-blade eddy current generators delayed the stall angle of attack by 0.7° and increased maximum lift by 0.082°.

[0070] The above are merely preferred embodiments of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should be considered within the scope of protection of the present invention.

Claims

1. A method for installing a large civil aircraft vortex generator modification component, characterized in that, The method includes the following steps: Step 1: Based on the aerodynamic characteristics of the aircraft, determine the specific structure and installation location of the vortex generator; Step 2: Determine the structure of the eddy current generator modification parts; Step 3: Construct a prefabricated eddy current generator modification component on the ground; Step 4: Clean and protect the installation location to ensure the installation area is ready; Step 5: Use a positioning tool to mark the installation location of the eddy current generator modification part; Step 6: Use high-strength structural adhesive to fix the eddy current generator in the predetermined position; Step 7: Clean the surface and seal the edges after the impregnating adhesive has fully cured; Step 8: After installation, conduct flight tests and evaluate the effect of the eddy current generator on improving lift coefficient and stall delay.

2. The installation method according to claim 1, characterized in that, In step 1, the vortex generator is installed at the wing root, specifically above the wing fairing; the vortex generator body is a fin-shaped lightweight structure, and the installation angle is 15° to 30°.

3. The installation method according to claim 1, characterized in that, In step 2: the eddy current generator modification component adopts a composite material sandwich structure, and the materials selected for each part are as follows: 2.1 The main structure of the modified part adopts a 3D printed sandwich core; 2.2 The inner and outer surfaces of the sandwich core are made of a 0.2mm glass fiber reinforced panel; 2.

3. A prefabricated body of a simulated eddy current generator modification component is formed by wrapping a core with a glass fiber reinforced panel and using a ground mold. 2.

4. The prefabricated body is attached to the surface of the machine body.

4. The installation method according to claim 1, characterized in that, In step 3, the method for fabricating the prefabricated eddy current generator modification component is as follows: 3.1 First, evenly apply butter to the surface of the leading edge mold of the wing, then cover it with plastic film. Use a scraper to remove air bubbles inside the plastic film so that there are no obvious wrinkles. 3.

2. Fit and fix the modified parts with the 3D printed mold; 3.3 Cut a 0.2mm twill fabric according to the outer surface dimensions of the modified part; 3.

4. Prepare an adhesive solution by mixing epoxy resin, diphenylene phthalate and dibutyl phthalate in a mass ratio of 100:20:10 and stirring until homogeneous. 3.

5. Lay 0.2mm twill fabric flat on the outer surface of the modified part, and use a brush to apply adhesive to the twill fabric. During the operation, use a brush to apply a small amount of adhesive each time to remove air bubbles; 3.6 Wipe away any excess adhesive from the edges with alcohol; 3.7 After 24 hours of curing time, remove the preform from the mold, peel off the inner plastic film, and use an angle grinder to trim the edges appropriately.

5. The installation method according to claim 1, characterized in that, In step 4: 3M aluminum tape is overlapped and pasted along the spanwise direction on the surface of the installation area. The wing and the surface of the aluminum tape are cleaned before and after pasting the aluminum tape.

6. The installation method according to claim 1, characterized in that, In step 5: the prepared modification part is positioned and fitted with the front edge skin, and the distance between the modification part and the positioning point is measured for accurate positioning. The bonding area between the inner surface of the modification part and the surface of the skin is drawn on the aluminum tape.

7. The installation method according to claim 1, characterized in that, In step 6: the structural adhesive is a high-strength epoxy resin adhesive. After mixing adhesive A and adhesive B in a 1:1 ratio, the mixture is evenly applied to the inner surface of the precast body of the eddy current generator modification part. The precast body is installed according to the edge line on the skin and fixed with masking tape.

8. The installation method according to claim 1, characterized in that, In step 7: after the impregnating adhesive has fully cured, seal the edges with metal tape.

9. The installation method according to claim 1, characterized in that, In step 8: After installation, a flight test is conducted and the effect of improving lift coefficient and delaying stall is verified by comparing with that of not installing vortex generator.

Images