CN111532417A - Aircraft radar stealth airfoil and preparation method thereof - Google Patents
Aircraft radar stealth airfoil and preparation method thereof Download PDFInfo
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- CN111532417A CN111532417A CN202010400428.0A CN202010400428A CN111532417A CN 111532417 A CN111532417 A CN 111532417A CN 202010400428 A CN202010400428 A CN 202010400428A CN 111532417 A CN111532417 A CN 111532417A
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- wave
- airfoil
- absorbing material
- wedge
- coating
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C3/00—Wings
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D7/00—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials
- B05D7/14—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials to metal, e.g. car bodies
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D7/00—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials
- B05D7/24—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials for applying particular liquids or other fluent materials
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C3/00—Wings
- B64C3/10—Shape of wings
- B64C3/14—Aerofoil profile
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C30/00—Supersonic type aircraft
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64F—GROUND OR AIRCRAFT-CARRIER-DECK INSTALLATIONS SPECIALLY ADAPTED FOR USE IN CONNECTION WITH AIRCRAFT; DESIGNING, MANUFACTURING, ASSEMBLING, CLEANING, MAINTAINING OR REPAIRING AIRCRAFT, NOT OTHERWISE PROVIDED FOR; HANDLING, TRANSPORTING, TESTING OR INSPECTING AIRCRAFT COMPONENTS, NOT OTHERWISE PROVIDED FOR
- B64F5/00—Designing, manufacturing, assembling, cleaning, maintaining or repairing aircraft, not otherwise provided for; Handling, transporting, testing or inspecting aircraft components, not otherwise provided for
- B64F5/10—Manufacturing or assembling aircraft, e.g. jigs therefor
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64U—UNMANNED AERIAL VEHICLES [UAV]; EQUIPMENT THEREFOR
- B64U20/00—Constructional aspects of UAVs
- B64U20/10—Constructional aspects of UAVs for stealth, e.g. reduction of cross-section detectable by radars
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C3/00—Wings
- B64C3/10—Shape of wings
- B64C3/14—Aerofoil profile
- B64C2003/149—Aerofoil profile for supercritical or transonic flow
Abstract
The invention belongs to the technical field of radar stealth aircraft design, and particularly relates to a metal substrate stealth airfoil surface component suitable for a subsonic aircraft and a preparation method thereof. The front edge of the airfoil consists of a metal material and a wave-absorbing material, wherein the metal material is in a wedge shape, the wave-absorbing material is distributed on two inclined planes of the wedge in an upper part and a lower part and is solidified with the wedge into a whole, the primary wave-absorbing material is thinner near the top point and the bottom of the wedge, the thickness is larger near the middle position of the inclined planes of the wedge, and the solidified airfoil is smooth in appearance.
Description
Technical Field
The invention belongs to the technical field of radar stealth for weaponry, and particularly relates to an aircraft radar stealth airfoil and a preparation method thereof.
Background
The missile wing is an important electromagnetic radiation part of a missile or a military aircraft, in order to reduce radar echo of the aircraft and better realize radar stealth of various military aircraft, a radar wave-absorbing coating material or a radar wave-absorbing patch material with certain thickness is usually applied to the outer surface of the missile wing, a certain stealth effect can be realized by the method, but the thickness of the material is about 1mm generally, and the conventional application mode is to apply the wave-absorbing coating material with the same thickness to the front edge part generally, so that the missile wing is suitable for the wing with larger wing surface size and the radius of the front edge of the wing surface larger than 10 mm.
When the radius of the leading edge of the airfoil is less than 10mm, if the wave-absorbing material with the same thickness is directly coated on the leading edge, the falling-off can be easily caused under the action of external force after the wave-absorbing material is applied.
Moreover, the thickness specification of the wave-absorbing material is generally 0.5 mm-1.5 mm, and if the application mode of equal thickness is adhered to, the invisible airfoil surface after the coating is applied can obviously change the aerodynamic appearance of the original airfoil surface. On the other hand, if the shape of the metal airfoil leading edge piece is integrally sunk to a certain thickness (such as 0.5mm), and then the wave-absorbing coating with the same thickness as the lower limit is sprayed, although the change of the aerodynamic shape can be compensated to a certain extent, at the rear edge part of the wave-absorbing material, because the surface of the metal base material has dead corners and is difficult to carry out surface treatment, the prepared coating easily has local defects.
Nie and Ying, Yuxiong Qing and so on in 2007 journal of aviation newspapers and Airfoil surface stealth structure electromagnetic scattering characteristic steady optimization design research provide a stealth structure scheme applied to wings, which mainly comprises the steps of placing a sharp-cleaved metal aluminum foil at the front part of a wing beam of the wing, and applying a multilayer foam material with larger thickness between the aluminum foil and a wave-transparent outer skin to realize the radar stealth effect. The method has the advantages that the occupied structural space is large, the space reserved for the structural force bearing metal material is too small, the radar stealth requirement of the small airfoil surface is difficult to meet, and for the large airfoil surface, if the wave absorbing foam in the structure is completely replaced by the coating type wave absorbing material, the structural weight is obviously increased, and after the method is applied to an aircraft, the structural weight is large, and the improvement of the flight performance is not facilitated.
In conclusion, the existing coating type stealth materials and structural type stealth materials in China have certain defects, and the radar stealth problem of the subsonic-velocity round-head aircraft is difficult to well meet.
Disclosure of Invention
The technical scheme of the invention is to overcome the defects of low bonding force and limited structural space in the existing airfoil stealth technical scheme, and provide a novel airfoil which adopts a wedge-shaped metal substrate and is coated with wave-absorbing coating materials with different thicknesses to obtain the appearance of a round-head leading edge and a preparation method thereof.
The scheme has the characteristics of good construction manufacturability and strong coating binding force, can be applied to various subsonic stealth aircrafts and preparation methods thereof, is particularly suitable for small and medium military stealth aircrafts, and simultaneously has the radar stealth performance of applied parts superior to that of conventional radar coating stealth aircrafts.
The technical scheme of the invention is as follows:
the radar stealth airfoil of the aircraft comprises a metal material part and a wave-absorbing material part, wherein the metal material part is wedge-shaped in appearance, the wave-absorbing material part is divided into an upper part and a lower part, is distributed on two inclined planes of the wedge and is solidified with the wedge into a whole, the thickness of the wave-absorbing material part is thinner near the top point and the bottom of the wedge, the thickness of the wave-absorbing material part is larger near the middle position of the inclined plane of the wedge, and the solidified airfoil is smooth in appearance.
The radar stealth airfoil is further optimized and improved on the basis of the above, and the wedge shape of the metal material is further optimized into a shape with gradually changed slope.
In practical use, the outer surfaces of the metal material and the wave-absorbing material are coated with protective finish paint materials.
The radar stealth airfoil with further optimized and improved performance on the basis of the above is coated with a wave-absorbing material, and the airfoil is a subsonic profile with the leading edge radius of 5 mm-20 mm.
The preparation method of the radar stealth missile wing can be processed and molded according to the following method:
(1) processing metallic materials
Machining and forming the metal material of the wing surface by adopting a conventional construction process;
(2) processing wave-absorbing material
Polishing and cleaning the surface of the adhered part of the metal material, then coating radar absorbing coating on the front edge of the metal material in a spraying or brushing way, and repeatedly coating for many times to ensure that the thickness of the coating reaches or exceeds the structural design thickness;
(3) post-treatment
After the coating is cured, the part of the wave-absorbing material higher than the designed thickness is polished and shaped, so that the smooth appearance of the wave-absorbing coating is ensured.
The preparation method of the radar stealth missile wing can be further processed and molded according to the following method:
(1) processing metallic materials
Machining and forming the metal material of the wing surface by adopting a conventional construction process;
(2) processing wave-absorbing material paster
According to the designed appearance, upper and lower patches of the wave-absorbing material with the three-dimensional shape consistent with that of the application part are prepared in a mould;
(3) pasting and forming of wave-absorbing material
And after polishing and surface cleaning treatment are carried out on the pasting part on the metal material, respectively pasting the upper and lower patches of the prepared wave-absorbing material on the application part to obtain the radar stealth airfoil.
The invention has the advantages of
The invisible airfoil surface coating wave-absorbing material mainly considers the performance indexes of high mechanical property and outstanding radar echo attenuation effect.
For the radius airfoil, the mechanical property of the conventional uniform coating technical measure of the wave-absorbing coating is limited by two aspects: first, after the front edge sinks, when the substrate is polished, polishing point contact is mainly performed on the convex surface with the curvature radius of the front edge, and a part which is not fully polished is easily left, and the situation is more serious when the radius of the front edge is smaller. And the edge part after wave absorption also can leave the clean dead angle of polishing, all can influence polishing and clean quality, influence the coating adhesive force. Meanwhile, for the coating with the same thickness, because the expansion coefficient of the coating is different from that of the metal base material, the edge position of the coating is easy to generate stress concentration, and therefore, the coating is easy to fall off when the coating is subjected to external force.
In the technical scheme provided by the invention, in consideration of electrical property, after the leading edge of the airfoil is designed to be in a split shape, when the airfoil is in a horizontal position, radar waves of an enemy are mainly incident in a direction close to a chord plane, a part of the radar waves enter the wave absorbing layer of the airfoil to be absorbed, the unabsorbed part of the radar waves is deflected after irradiating the oblique wedge, and the echo direction is far away from the incident direction. And the traditional technical measures for coating the wave-absorbing material do not consider utilizing the mechanism. Therefore, the invention can realize better electrical performance indexes, particularly the large-curvature radius airfoil with stronger mirror effect, and has better echo suppression effect compared with the conventional scheme.
In the improved technical scheme provided by the invention, the metal substrate of the front edge piece is designed into a curved surface with continuously changing curvature, so that the electromagnetic echo generated by abrupt change of curvature radius and abrupt change of material properties can be further reduced, and a more favorable echo attenuation effect is realized. The method is characterized in that the leading edge of the metal airfoil is prepared into a wedge shape, and crescent-shaped stealth paint is coated on the outer side of the wedge.
In a specific preparation mode, the wave-absorbing material can be prepared by coating the coating on the metal material for multiple times in one or two modes of spraying and brushing for curing, or can be prepared into a film with a specific shape according to the existing formula and then adhered to a part. The former does not need an adhesive layer, the electrical property is better, and the construction time of the latter is shorter.
Drawings
The invention has 2 figures.
FIG. 1 is a schematic cross-sectional view of an airfoil designed using the present invention, wherein the metallic material leading edge is in the form of a wedge.
FIG. 2 is a schematic cross-sectional view of an optimized airfoil designed according to the present invention, in which the wedge-shaped surface of the metallic leading edge is smoothly transitioned with other outer surfaces of the airfoil.
FIG. 1-RAM coating, 2-Metal substrate
Detailed Description
The invention is further described with reference to the following figures and specific embodiments.
Example 1
The shape of the section of the front edge of the missile wing is shown in figure 1, wherein the radius of the front edge is 10mm, the width of the wedge is 25mm, the subsonic naca wing type is adopted, and the relative thickness of the wing surface is 10%.
The airfoil is formed by processing as follows:
(1) processing metallic materials
Machining and forming the metal material of the wing surface by adopting a conventional construction process;
(2) processing wave-absorbing material
After polishing and surface cleaning treatment are carried out on the adhered part on the metal material, a spraying or brushing way is adopted, and a commercially available radar wave-absorbing coating is coated on the front edge of the metal material, and the thickness of the coating reaches or exceeds the structural design thickness through repeated coating for many times;
(3) post-treatment
After the coating is cured, the part of the wave-absorbing material higher than the designed thickness is polished and shaped, so that the smooth appearance of the wave-absorbing coating is ensured.
Example 2:
the shape of the section of the front edge of the missile wing is shown in figure 2, wherein the radius of the front edge is 5mm, the rear end of the wedge-shaped surface is in smooth transition with the appearance of the missile wing, the pasting width of the wave-absorbing material is 30mm, the subsonic naca wing is adopted, and the relative thickness of the wing surface is 10%.
The airfoil is formed by processing as follows:
(1) processing metallic materials
Machining and forming the metal material of the wing surface by adopting a conventional construction process;
(2) processing wave-absorbing material paster
According to the designed appearance, an upper patch and a lower patch which are consistent with the three-dimensional shape of the application part are prepared in the mould.
For convenient subsequent sticking, the upper and lower patches are prepared into adjacent whole pieces
(3) Pasting and forming of wave-absorbing material
And after polishing and surface cleaning treatment are carried out on the pasting part on the metal material, the prepared upper and lower patches are respectively pasted on the application part, and the stealth airfoil is obtained.
Example 3:
the shape of the section of the front edge of the missile wing is shown in figure 2, wherein the radius of the front edge is 20mm, the rear end of the wedge-shaped surface is in smooth transition with the appearance of the missile wing, the pasting width of the wave-absorbing material is 40mm, the subsonic naca wing is adopted, and the relative thickness of the wing surface is 12%.
The airfoil is formed by processing as follows:
(1) processing metallic materials
Machining and forming the metal material of the wing surface by adopting a conventional construction process;
(2) processing wave-absorbing material paster
According to the designed appearance, an upper patch and a lower patch which are consistent with the three-dimensional shape of the application part are prepared in the mould.
For convenient subsequent sticking, the upper and lower patches are prepared into adjacent whole pieces
(3) Pasting and forming of wave-absorbing material
And after polishing and surface cleaning treatment are carried out on the pasting part on the metal material, the prepared upper and lower patches are respectively pasted on the application part, and the stealth airfoil is obtained.
Claims (6)
1. An aircraft radar stealth airfoil characterized by: the front edge position of the airfoil consists of a metal material part and a wave-absorbing material part, wherein the metal material part is in a wedge shape, and the wave-absorbing material part is divided into an upper part and a lower part which are distributed on two inclined planes of the wedge, are solidified with the wedge into a whole and are in a crescent shape; the thickness of the wave-absorbing material from the top point of the wedge and the bottom of the wedge is smaller than that of the wave-absorbing material in the middle of the inclined plane of the wedge.
2. The radar stealth airfoil of claim 1, wherein: the wedge shape of the metal material is a shape with a gradually changed slope.
3. The radar stealth airfoil of claim 1, wherein: and protective finish paint materials are coated on the outer surfaces of the metal material and the wave-absorbing material.
4. The radar stealth airfoil of claim 1, wherein: after the wave-absorbing material is coated, the radius of the leading edge of the airfoil is less than 5 mm.
5. The method for manufacturing the radar stealth airfoil according to any one of claims 1 to 4, wherein the forming is performed by the following method:
(1) processing metallic materials
Machining and forming the metal material of the wing surface by adopting a conventional construction process;
(2) processing wave-absorbing material
Polishing and cleaning the surface of the adhered part of the metal material, then coating radar absorbing coating on the front edge of the metal material in a spraying or brushing way, and repeatedly coating for many times to ensure that the thickness of the coating reaches or exceeds the structural design thickness;
(3) post-treatment
After the coating is cured, the part of the wave-absorbing material higher than the designed thickness is polished and shaped, so that the smooth appearance of the wave-absorbing coating is ensured.
6. The method for manufacturing the radar stealth airfoil according to any one of claims 1 to 4, wherein the forming is performed by the following method:
(1) processing metallic materials
Machining and forming the metal material of the wing surface by adopting a conventional construction process;
(2) processing wave-absorbing material paster
According to the designed appearance, upper and lower patches of the wave-absorbing material with the three-dimensional shape consistent with that of the application part are prepared in a mould; (3) pasting and forming of wave-absorbing material
And after polishing and surface cleaning treatment are carried out on the pasting part on the metal material, respectively pasting the upper and lower patches of the prepared wave-absorbing material on the application part to obtain the radar stealth airfoil.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN202010400428.0A CN111532417A (en) | 2020-05-13 | 2020-05-13 | Aircraft radar stealth airfoil and preparation method thereof |
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| CN202010400428.0A CN111532417A (en) | 2020-05-13 | 2020-05-13 | Aircraft radar stealth airfoil and preparation method thereof |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112407236A (en) * | 2020-10-27 | 2021-02-26 | 成都飞机工业（集团）有限责任公司 | Honeycomb sandwich graphene stealth front edge and processing method thereof |
| CN114006164A (en) * | 2021-11-01 | 2022-02-01 | 中国电子科技集团公司第三十八研究所 | Method for fixing wave-absorbing material in inner cavity of radar cast aluminum cover plate |
| CN114194374A (en) * | 2021-12-15 | 2022-03-18 | 江西洪都航空工业股份有限公司 | Wing and machining method thereof |
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Application publication date: 20200814 |