Impact resistant blade composite structure

Abstract

The present application belongs to the technical field of blade structure of cross-medium aircraft rotor, and particularly relates to a shock-resistant blade composite material structure. The shock-resistant blade composite material structure comprises a surface shock-resistant coating, a skin, a spanwise load-bearing beam, a frame beam surface carbon cloth, a frame beam, a transverse reinforcing rib, a spanwise reinforcing rib and filling foam. The frame beam surface carbon cloth is pasted on the surface of the frame beam. The spanwise reinforcing rib is in a half I-shaped structure. The transverse reinforcing rib is made of carbon cloth and has a "sun" shaped structure. The upper and lower surfaces of the transverse reinforcing rib are bonded to the skin. The left side of the transverse reinforcing rib is bonded to the arc surface of the frame beam. The right side of the transverse reinforcing rib is bonded to the left side of the spanwise reinforcing rib. The transverse reinforcing rib is formed in the middle of the transverse reinforcing rib. The spanwise load-bearing beam is arranged between the frame beam and the skin. The inside of the transverse reinforcing rib and the space between the spanwise reinforcing rib and the skin are filled with the filling foam. The surface shock-resistant coating covers the whole blade surface.

Description

Technical Field

[0001] The present invention belongs to the technical field of rotor blade structures for trans-medium aircraft, and specifically relates to an impact-resistant composite structure for a blade. Background Art

[0002] Trans-medium aircraft operate in both air and water conditions, and have the advantages of vertical take-off and landing of aerial aircraft and high concealment of underwater vehicles, making them a research hotspot. The rotor is a key component of the aircraft, providing lift and thrust for the aircraft. However, during the take-off and landing phases of the trans-medium aircraft on the water surface, splashes or water columns will be generated. When the high-speed rotating blade, especially the part near the blade tip (with a high linear velocity of ≥200m / s), hits the water column, large impact damage will occur, so it is necessary to reinforce and protect the internal structure of the blade. Conventional structural reinforcement is to bond an iron clad or a polyurethane protective strip to the leading edge, but the iron clad or polyurethane protective strip is prone to debonding in a water-immersed environment, which is not suitable for trans-medium aircraft, and there is no structure reinforced along the chord direction inside the conventional blade, resulting in weak structural strength in the chord direction. Summary of the Invention

[0003] Object of the invention: To provide an impact-resistant composite structure for a blade, which solves the problem that the aircraft rotor is damaged by water impact during the take-off and landing phases.

[0004] Technical Solution

[0005] An impact-resistant composite structure for a blade, comprising: a surface impact-resistant coating 1, a skin 2, a spanwise load-bearing girder 3, carbon cloth 4 on the surface of a frame girder, a frame girder 5, a transverse reinforcing rib 6, a spanwise reinforcing rib 7, and a filling foam 8,

[0006] Wherein, the frame girder 5 comprises two planes in the chord direction and an arc surface along the thickness direction of the blade, and the ends of the two planes in the chord direction are respectively bonded to the leading edge skin; the surface of the frame girder 5 is pasted with the carbon cloth 4 on the surface of the frame girder, the spanwise reinforcing rib 7 has a semi-I-shaped structure, the transverse reinforcing rib 6 is made of carbon cloth and has a "day"-shaped structure, the upper and lower surfaces of the transverse reinforcing rib 6 are bonded to the skin, the left side of the transverse reinforcing rib 6 is bonded to the arc surface of the frame girder 5, the right side of the transverse reinforcing rib 6 is bonded to the left side of the spanwise reinforcing rib 7, and a transverse reinforcing rib is formed in the middle of the transverse reinforcing rib 6; the spanwise load-bearing girder 3 is arranged between the frame girder 5 and the skin 2; the interior of the transverse reinforcing rib 6 and the space between the spanwise reinforcing rib 7 and the skin 2 are both filled with the foam 8, and the surface impact-resistant coating 1 covers the entire outer surface of the blade.

[0007] Further, the frame girder 5 is made of woven cloth or unidirectional cloth, the main fiber direction of the material is along the chord direction of the blade to increase the transverse stiffness, and the frame girder is preformed.

[0008] Furthermore, the surface impact-resistant coating 1 is a polyurea coating or a polyurethane coating, the purpose of which is to provide waterproofing and impact resistance. The thickness is controlled within 0.5mm to ensure waterproofing and impact resistance while reducing the impact on the aerodynamic shape of the blade.

[0009] Furthermore, the outermost layer of the skin 2 is made of high-strength HS6 woven glass cloth to enhance impact damage tolerance.

[0010] Furthermore, the spanwise load-bearing beam 3 is made of HS6 high-strength glass fiber prepreg tape, laid along the blade spanwise direction to improve the blade tensile stiffness.

[0011] Furthermore, the carbon cloth 4 on the surface of the frame beam is woven in the 0 / 90 direction and attached to the frame beam 5 to increase the lateral stiffness.

[0012] Furthermore, the transverse reinforcing rib 6 is made of carbon cloth.

[0013] Furthermore, the filling foam 8 is a high-density polymethyl methacrylate (PMI) foam with a density requirement of ≥110Kg / m3 and a compressive strength of ≥1.5MPA.

[0014] Beneficial effects:

[0015] The propeller blades of the cross-medium aircraft adopt the impact-resistant composite material structure of the present invention, which can improve the water impact resistance of the propeller blades during the water entry and exit phases, avoid the propeller blades from meeting the anti-corrosion and anti-fouling requirements of long-term immersion in water, and improve the safety margin of the propeller blades. Attached Figure Description

[0016] Figure 1 This is a cross-sectional view of the internal structure of the blade;

[0017] Figure 2 for Figure 1 A magnified view of a portion of the image;

[0018] In the figure, 1 is the impact-resistant coating, 2 is the skin, 3 is the spanwise load-bearing beam, 4 is the carbon cloth on the surface of the frame beam, 5 is the frame beam, 6 is the transverse reinforcing rib, 7 is the spanwise reinforcing rib, and 8 is the filling foam. Detailed Implementation

[0019] The following is a detailed explanation with reference to the accompanying drawings.

[0020] like Figure 1 and Figure 2 An impact-resistant composite material structure for a cross-medium aircraft blade includes: a surface impact-resistant coating 1, a skin 2, a spanwise load-bearing beam 3, a carbon cloth on the surface of the frame beam 4, a frame beam 5, transverse reinforcing ribs 6, spanwise reinforcing ribs 7, and foam filling 8.

[0021] The surface coating 1 covers the entire outer surface of the blade, and the coating type is polyurea coating or polyurethane-based coating, which aims at waterproofing and impact resistance, with the thickness controlled within 0.5mm, so as to ensure the waterproof and impact resistance performance while reducing the influence on the aerodynamic profile of the blade;

[0022] The outermost layer of the skin 2 is high-strength HS6 woven glass fabric to improve the impact damage tolerance capability;

[0023] The material of the spanwise load-bearing spar 3 is HS6 high-strength glass fiber prepreg tape, which is laid along the spanwise direction of the blade to improve the tensile stiffness of the blade;

[0024] The carbon fabric 4 on the surface of the frame spar is a 0 / 90 direction woven carbon fabric, which is attached to the frame spar to increase the transverse stiffness

[0025] The material of the frame spar 5 is a thermoplastic composite material, which can be woven fabric or unidirectional fabric, the main fiber direction of the material is along the chordwise direction of the blade to increase the transverse stiffness, and the frame spar is preformed;

[0026] The material of the transverse reinforcing rib 6 is carbon fabric, the structure is in the shape of the Chinese character "日", the upper and lower parts are bonded to the skin, and the transverse reinforcing rib is formed in the middle;

[0027] The spanwise reinforcing rib 7 structurally abuts against the transverse reinforcing rib 6;

[0028] The filling foam 8 is high-density polymethacrylimide (PMI) foam, with the density requirement ≥110Kg / m³ and the compressive strength ≥1.5MPA;

[0029] The reinforcing rib 7 is in the shape of the Chinese character "工", made of carbon fabric, which divides the filling foam into two halves to further improve the impact resistance;

[0030] The frame spar 5 is preformed, the spanwise load-bearing spar 3 is inserted into the frame of the frame spar 5, and is integrally molded by compression with the skin 2, the carbon fabric 4 on the surface of the frame spar, the transverse reinforcing rib 6, the spanwise reinforcing rib 7 and the filling foam 8, and the surface impact-resistant coating 1 is sprayed on the surface of the compression-molded blade.

[0031] The key points of the present invention are: 1. The main beam of the frame (5) is made of thermoplastic composite material, and the fiber direction of the material is along the chord length direction of the blade to increase the lateral stiffness, and the main beam of the frame is prefabricated; 2. The structure of the transverse reinforcing rib (6) is in the shape of a Chinese character "ri", the upper and lower parts are bonded to the skin, and the transverse reinforcing rib is formed in the middle; 3. The spanwise load-bearing main beam (3) is inserted into the frame of the frame main beam (5) to form a combined body with strong structural strength in both directions; 4. The blade surface coating covers the outer surface of the blade, and the type is polyurea coating or polyurethane coating; 5. The outermost layer of the skin is high-strength woven glass cloth to improve the impact resistance; 6. The main beam is made of HS6 high-strength glass fiber prepreg tape, which is laid along the spanwise direction of the blade; 7. The filling foam (8) is high-density polymethacrylimide (PMI) foam, with a density requirement of ≥110Kg / m3 and a compressive strength of ≥1.5MPA; 8. The frame main beam (5) is prefabricated, and the other parts are formed by one-time compression molding.

Claims

1. An impact-resistant propeller composite material structure, characterized in that, comprising: a surface impact-resistant coating (1), a skin (2), a spanwise load-bearing spar (3), carbon cloth on the surface of the frame girder (4), a frame girder (5), a transverse reinforcing rib (6), a spanwise reinforcing rib (7), and a filling foam (8), wherein the frame girder (5) comprises two chordwise planes and an arc surface along the thickness direction of the blade, and the ends of the two chordwise planes are respectively bonded to the leading edge skin; the surface of the frame girder (5) is adhered with the carbon cloth (4) on the surface of the frame girder; the spanwise reinforcing rib (7) has a half-I-shaped structure; the transverse reinforcing rib (6) is made of carbon cloth and has a "day"-shaped structure, the upper and lower surfaces of the transverse reinforcing rib (6) are bonded to the skin, the left side of the transverse reinforcing rib (6) is bonded to the arc surface of the frame girder (5), the right side of the transverse reinforcing rib (6) is bonded to the left side of the spanwise reinforcing rib (7), and a transverse reinforcing rib is formed in the middle of the transverse reinforcing rib (6); the spanwise load-bearing spar (3) is arranged between the frame girder (5) and the skin (2); the interior of the transverse reinforcing rib (6) and the space between the spanwise reinforcing rib (7) and the skin (2) are both filled with the foam (8), and the surface impact-resistant coating (1) covers the entire outer surface of the blade.

2. The impact-resistant blade composite material structure according to claim 1, characterized in that, The frame girder (5) is made of woven fabric or unidirectional fabric, the main fiber direction of the material is along the chordwise direction of the blade to increase the transverse stiffness, and the frame girder is preformed.

3. The impact-resistant blade composite material structure according to claim 1, characterized in that, The surface impact-resistant coating (1) is a polyurea coating or a polyurethane-based coating, which is intended for waterproofing and impact resistance, and the thickness is controlled within 0.5mm, so as to ensure the waterproof and impact resistance performance while reducing the influence on the aerodynamic profile of the blade.

4. The impact-resistant blade composite material structure according to claim 1, characterized in that, The outermost layer of the skin (2) is a high-strength HS6 woven glass fabric to improve the impact damage tolerance capability.

5. The impact-resistant blade composite material structure according to claim 1, characterized in that, The spanwise load-bearing spar (3) is made of HS6 high-strength glass fiber prepreg tape, which is laid along the spanwise direction of the blade to improve the tensile stiffness of the blade.

6. The impact-resistant blade composite material structure according to claim 1, characterized in that, The carbon cloth (4) on the surface of the frame girder is a 0 / 90 direction woven carbon cloth, which is adhered to the frame girder (5) to increase the transverse stiffness.

7. The impact-resistant blade composite material structure according to claim 1, characterized in that, The transverse reinforcing rib (6) is made of carbon cloth.

8. The impact-resistant blade composite material structure according to claim 1, characterized in that, The filling foam (8) is a high-density polymethacrylimide PMI foam, with a density requirement of ≥110Kg / m³ and a compressive strength of ≥1.5MPa.

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