A composite fairing docking frame sealing structure and its design method

Abstract

The present invention provides a sealing structure for a composite fairing docking frame, which includes an upper fairing docking frame, a lower fairing docking frame, a sealing layer, a plurality of explosion bolts, an explosion bolt box, and gaskets. The sealing layer is located in the gap between the upper fairing docking frame and the lower fairing docking frame. The upper fairing docking frame and the lower fairing docking frame are connected by the explosion bolts. An explosion bolt box is arranged around the explosion bolts. Gaskets are arranged below the explosion bolt boxes, and the gaskets are located in the gap between the upper fairing docking frame and the lower fairing docking frame. The design method of the sealing structure for the composite fairing docking frame of the present invention distinguishes the main influencing factors and secondary influencing factors in the mutual extrusion and deformation coordination of the structure, grasps the design key points, and reduces the design cycle and cost.

Description

Technical Field

[0001] The present invention belongs to the field of aerospace, and particularly relates to a sealing structure for the docking frame of a composite fairing and a design method thereof. Background Art

[0002] The fairing is used to protect satellites and other payloads to prevent the satellites from being affected by harmful environments such as aerodynamic force, aerodynamic heating, and acoustic vibration, and is an important part of aerospace vehicles. The fairing is generally of a clam shell (two halves) structure and consists of a nose, a front cone section, a cylindrical section, an inverted cone section, and longitudinal and transverse separation mechanisms, etc. The rocket fairing is composed of two half fairings, and there is a docking frame at the docking surface of the two half fairings for connection, and the docking frame is connected by explosion bolt boxes on both sides of the docking interface.

[0003] The two half fairings of the fairing are connected by explosion bolts, and the docking frames of the two half fairings squeeze the silicone rubber on the docking surface to achieve sealing. The elastic force of the silicone rubber may cause obvious warping deformation of the docking frame. The fairing body and the docking frame of the composite fairing are of an integrally formed structure. This forming method can reduce weight and improve performance, but the trial-and-error cost is high. Therefore, quantitatively calculating and reducing the warping deformation of the docking frame of the composite fairing in the early stage of the scheme design is an important link in the sealing design of the composite rubber strip sealed fairing. Summary of the Invention

[0004] In view of this, the present invention aims to overcome the defects in the prior art and proposes a sealing structure for the docking frame of a composite fairing and a design method thereof.

[0005] To achieve the above object, the technical solution of the present invention is realized as follows:

[0006] A sealing structure for the docking frame of a composite fairing, comprising a docking upper frame of the fairing, a docking lower frame of the fairing, a sealing layer, and a plurality of explosion bolts. The sealing layer is located in the gap between the docking upper frame of the fairing and the docking lower frame of the fairing. The docking upper frame of the fairing and the docking lower frame of the fairing are connected by the explosion bolts. An explosion bolt box is arranged outside the explosion bolts. Gaskets are arranged below the explosion bolt boxes, and the gaskets are located in the gap between the docking upper frame of the fairing and the docking lower frame of the fairing. The size of the gaskets determines the sealing effect of the docking frame.

[0007] Further, the gaskets are made of metal material; the material of the sealing layer is silicone rubber.

[0008] Further, the length of the sealing layer is more than five times the length of the gaskets. The sealing layer is bonded to the docking lower frame of the fairing.

[0009] A design method for the sealing structure of the docking frame of the composite fairing as described above includes the following steps:

[0010] (1) Conduct small-scale experiments with different sizes to establish a database of L1, H2, and M1;

[0011] (2) Calculate H2 based on the actual flatness of the docking frame;

[0012] (3) Calculate the value of M1 according to the limited deflection V1 and the known L2;

[0013] (4) Substitute the obtained values of H2 and M1 into the said database to obtain the corresponding L1.

[0014] Furthermore, the L1 is half of the gasket length (the gasket is symmetric about the axis of the explosion bolt) or the length on one side of the axis of the explosion bolt (the gasket is asymmetric about the axis of the explosion bolt), L2 is half of the length of the sealing layer, H2 is the thickness of the sealing layer, M1 is the bending moment value at the contact points of the upper and lower frames of the fairing docking on the gasket and the sealing layer, and V1 is the sum of the deflections of the upper and lower frames of the fairing docking.

[0015] Furthermore, the H2 in the step (2) is calculated by the following formula:

[0016] H2 = H1 + ΔH2 + (dH1 + dH2) (1).

[0017] Furthermore, the dH1 is the actual flatness of the upper frame of the fairing docking; the dH2 is the actual flatness of the lower frame of the fairing docking; the ΔH2 is the pre-compression amount; and the H1 is the gasket thickness.

[0018] Furthermore, the L2 in the step (3) is more than 5 times the L1.

[0019] Furthermore, the M1 in the step (3) is calculated by the following formula:

[0020] M1 = V1 × E × I / L2 2 (2).

[0021] Furthermore, the V1 is the deflection limit value, which is determined by the design requirements of the fairing; the elastic modulus E is the equivalent mechanical parameter of the composite fairing docking frame. The docking frame is simplified as an isotropic material, and the in-plane stiffness E of the orthotropic material is calculated by the laminate theory and used as the material parameter of the isotropic material; the moment of inertia I is the sectional geometric parameter of the composite fairing docking frame.

[0022] Compared with the prior art, the present invention has the following advantages:

[0023] The flatness of the integrally formed composite fairing docking frame is relatively poor. To ensure the sealing performance, a sealing layer is often used to seal the docking surface. However, this method is prone to the warping of the contact surface of the docking frame due to insufficient stiffness of the docking frame, resulting in a reduction in the sealing performance. Different from the conventional method of supplementing the cover plate after the warping of the docking frame is found, the present invention effectively reduces the warping of the docking frame by increasing the length of the metal gasket on the docking surface, solving the problem of the warping of the docking frame from the design end and enhancing the sealing performance and reliability of the fairing.

[0024] Increasing the length of the metal gasket will increase the weight of the structure. For a rocket fairing, the weight is a strictly controlled design requirement. To accurately calculate the size of the metal gasket, the present invention provides a design method for the sealing structure of the composite fairing docking frame, which distinguishes the main influencing factors and secondary influencing factors in the mutual extrusion and deformation coordination of the structure.

[0025] In the complex deformation coordination analysis, the research object is segmented with the contact point between the gasket and the sealing layer as the segmentation point. The bending moment of the docking frame at this point is mainly determined by the structure in the area between this point and the axis of the explosive bolt, and the correlation between the bending moment of the docking frame at this point and the length of the sealing layer is relatively small. Therefore, the influence of the length of the sealing layer is ignored. The effect of the bending moment of the docking frame at this point is to cause the contact surface between the upper docking frame and the sealing layer to warp. Through the above simplification, the complex solid mechanics problem is simplified into a material mechanics problem, grasping the design key points and reducing the calculation difficulty.

[0026] After the overall fairing scheme except for the sealing structure is determined, the present invention proposes a simple small-scale test method, which can quickly establish the relationship between the bending moment at the contact point of the gasket and the sealing layer and the length of the gasket and the thickness of the sealing layer. Facing different composite material forming qualities and product sealing requirements, the fairing sealing design scheme can be quickly obtained, reducing the design cycle. This design method can avoid repeated assembly tests on the composite fairing, avoid the overall scrapping of the integrated product caused by local damage to the composite material, and reduce the test cost and risk. Brief Description of the Drawings

[0027] The drawings forming a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings:

[0028] Figure 1 is a schematic diagram of the sealing structure of the composite fairing docking frame according to Embodiment 1 of the present invention;

[0029] Figure 2 is a schematic diagram of the sealing structure of the composite fairing docking frame according to Embodiment 2 of the present invention.

[0030] Description of the Reference Numerals:

[0031] 1. Explosion bolt; 2. Upper frame for fairing docking; 3. Lower frame for fairing docking; 4. Gasket; 5. Sealing layer; 6. Explosion bolt box. Detailed implementation mode

[0032] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0033] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation to the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise stated, the meaning of "a plurality" is two or more.

[0034] In the description of the present invention, it should be noted that unless otherwise clearly defined and limited, the terms "installation", "connection", "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood through specific situations.

[0035] The present invention will be described in detail below with reference to the drawings and in combination with embodiments.

[0036] Embodiment 1

[0037] As Figure 1 shown, the research object includes an explosion bolt 1, an upper frame 2 for fairing docking, a lower frame 3 for fairing docking, a metal gasket 4, silicone rubber (the sealing layer 5 uses silicone rubber), and an explosion bolt box 6. The silicone rubber is bonded to the lower frame 3 for fairing docking. By tightening the explosion bolt 1, the deformation of each structure is coordinated to be in a static state, and the upper frame 2 for fairing docking and the lower frame 3 for fairing docking are warped, with a total deflection of V1. The design goal is to limit V1 within a specified range.

[0038] The dimensions of the explosive bolt 1 include the diameter D1 of the explosive bolt 1; the dimensions of the upper fairing docking frame 2 include the thickness H3 and the width W1; the dimensions of the lower fairing docking frame 3 include the thickness H3 and the width W1; the dimensions of the gasket 4 include the thickness H1, half of the length L1, and the width W1; the dimensions of the silicone rubber include the thickness H2, half of the length L2, and the width W1; the dimensions of the explosive bolt box 6 include the thickness H6 of the contact surface with the gasket, half of the length L3 of the contact surface with the gasket, the width W1, the side length L4, the side thickness H4, and the top surface thickness H5. The direction of the width is Figure 1 the direction of the vertical view, and the dimensions of each structure are the same in this direction. The length is Figure 1 the longer dimension of each structure, and the thickness is Figure 1 the shorter dimension of each structure.

[0039] The product dimension L2 is more than 5 times that of L1. Therefore, the influence of the product dimension L2 on the bending moment value M1 at the contact point between the metal gasket 4 and the silicone rubber of the upper fairing docking frame 2 and the lower fairing docking frame 3 is very small and can be ignored.

[0040] The correlation between L2 and M1 belongs to the secondary influencing factor of the structural mutual extrusion. By ignoring the correlation between L2 and M1, the complex deformation coordination problem is simplified. The overall complex research object is divided at the contact point between the metal gasket 4 and the silicone rubber. It is assumed that the bending moment value M1 is only generated by the mutual extrusion of the structures in the area from the explosive bolt 1 to the contact point. The bending moment value M1 at the contact point acts alone on the docking upper frame and the docking lower frame that are in contact with the silicone rubber, causing the docking frame to deflect and deform. Such an assumption distinguishes the main influencing factors and the secondary influencing factors in the structural mutual extrusion and deformation coordination, grasps the design key points, and reduces the design cycle and cost.

[0041] According to the 11 parameters of L1, L3, L4, H1, H2, H3, H4, H5, H6, W1, and D1, an 11-dimensional matrix can be established, and different parameter combinations correspond to different bending moment values M1. When the overall structure scheme of a fairing is determined, 9 parameters of L3, L4, H1, H3, H4, H5, H6, W1, and D1 can be determined. Therefore, for a specific fairing sealing scheme, only a two-dimensional matrix with parameters L1 and H2 as variables needs to be established through small-scale tests to establish the corresponding relationship between L1, H2, and the bending moment value M1.

[0042] Using the same parameters as the fairing product, namely L3, L4, H1, H3, H4, H5, H6, W1, D1, produce a small-scale test piece. The half-length L2 of the silicone rubber of the test piece is more than 5 times the half-length L1 of the gasket; the elastic modulus E is the equivalent mechanical parameter of the composite fairing docking frame. Simplify the docking frame into an isotropic material, and calculate the in-plane stiffness E of the orthotropic material by the laminate theory as the material parameter of the isotropic material. The composite layup of the test piece and the composite fairing docking frame is the same, and the parameter E is the same; change L1 by modifying the assembly relationship, and select different thicknesses of H2, and measure the maximum deflection V1 after assembly; calculate the bending moment value M1 through the maximum deflection V1, the half-length L2 of the silicone rubber of the test piece, the docking frame width W1 and the docking frame thickness H3 on the test piece. The calculation formula is as follows:

[0043] I = W1 × H3 3 / 12

[0044] M1 = V1 × E × I / L2 2

[0045] The parameters of the test piece consistent with the fairing product include L3 = 50mm, L4 = 100mm, H1 = 2mm, H3 = 5mm, H4 = 5mm, H5 = 5mm, H6 = 5mm, W1 = 50mm, D1 = 16mm, and E = 100GPa. The data obtained from the small-scale test are shown in Table 1.

[0046] Table 1 Small-scale test data

[0047]

[0048] After completing the small-scale test, carry out product design. According to the flatness of the upper and lower docking frames of the actual product, calculate the thickness H2 of the silicone rubber using formula (1). dH1 is the measured flatness of the upper docking frame 2 of the fairing, and dH1 is measured according to the forming effect of the composite fairing; dH2 is the measured flatness of the lower docking frame 3 of the fairing, and dH2 is measured according to the forming effect of the composite fairing; ΔH2 is the pre-compression amount, and it is specified that ΔH2 = 0.4; H1 is the assembly gap of the fairing and is also the gasket thickness.

[0049] Calculate H2:

[0050] Example 1: The measured flatness dH1 of the upper docking frame of the fairing is 0.3, the measured flatness dH2 of the lower docking frame of the fairing is 0.3, and H2 = H1 + ΔH2 + (dH1 + dH2) = 3mm.

[0051] Example 2: The measured flatness dH1 of the upper docking frame of the fairing is 0.4, the measured flatness dH2 of the lower docking frame of the fairing is 0.4, and H2 = H1 + ΔH2 + (dH1 + dH2) = 3.2mm.

[0052] According to the design requirements of the fairing, determine the deflection limit value V1, and calculate the bending moment value M1 at the contact points of the upper frame 2 and the lower frame 3 of the fairing docking with the metal gasket 4 and the silicone rubber. The moment of inertia I is the cross-sectional geometric parameter of the composite fairing docking frame, which is consistent with the moment of inertia I of the test piece.

[0053] Calculate M1:

[0054] Example 1: The design requirement of the fairing is that the deflection limit value V1 is less than 0.2 mm. The width dimension W1 of the composite fairing docking frame is 50 mm, the thickness dimension H3 of the composite fairing docking frame is 5 mm, the equivalent elastic modulus of the composite material is 100 GPa, and L2 = 600 mm. Calculate the bending moment value M1 = 28.94 MPa according to the following formula.

[0055] M1 = V1 × E × I / L2 2

[0056] Example 2: The design requirement of the fairing is that the deflection limit value V1 is less than 0.2 mm. The width dimension W1 of the composite fairing docking frame is 50 mm, the thickness dimension H3 of the composite fairing docking frame is 5 mm, the equivalent elastic modulus of the composite material is 100 GPa, and L2 = 700 mm. Calculate the bending moment value M1 = 21.26 MPa according to the following formula.

[0057] M1 = V1 × E × I / L2 2

[0058] Calculate L1:

[0059] Example 1: Substitute H2 = 3 mm and M1 = 28.94 MPa into Table 1. The design value of L1 is taken as 54 mm. All design schemes of the sealing structure are completed. The product sealing performance meets the requirements, and the size of the metal gasket is reduced to the limit. The product has a light weight and is the optimal design scheme.

[0060] Example 2: Substitute H2 = 3.2 mm and M1 = 21.26 MPa into Table 1. The design value of L1 is taken as 57 mm. All design schemes of the sealing structure are completed. The product sealing performance meets the requirements, and the size of the metal gasket is reduced to the limit. The product has a light weight and is the optimal design scheme.

[0061] Example 2

[0062] As Figure 2As shown in the figure, the research object includes explosive bolts 1, fairing docking upper frame 2, fairing docking lower frame 3, metal gasket 4, silicone rubber, explosive bolt box 6, and the silicone rubber is bonded to fairing docking lower frame 3. By tightening explosive bolts 1, the deformation of each structure is coordinated and static, causing the fairing docking upper frame 2 and fairing docking lower frame 3 to warp, with a total deflection of V1. The design goal is to limit V1 to a specified range.

[0063] The dimensions of the explosive bolt 1 include the diameter D1 of the explosive bolt 1; the dimensions of the fairing docking upper frame 2 include the thickness H3 and the width W1; the dimensions of the fairing docking lower frame 3 include the thickness H3 and the width W1; the dimensions of the gasket 4 include the thickness H1, the width W1, the length L11 of the gasket on the bolt axis side between the middle bolt and the left bolt, and the length L12 of the gasket on the bolt axis side between the middle bolt and the right bolt; the dimensions of the silicone rubber include the thickness H2, the width W1, the half length L21 of the left silicone rubber, and the half length L22 of the right silicone rubber; the dimensions of the explosive bolt box 6 include the thickness H6 of the contact surface with the gasket, the half length L3 of the contact surface with the gasket, the width W1, the side length L4, the side thickness H4, and the top thickness H5. The width direction is Figure 2 In the direction perpendicular to the view, the dimensions of each structure are the same in this direction, and the length is Figure 2 The longer dimension of each structure, the thickness is Figure 2 The shorter dimension of each structure.

[0064] The product dimensions L21 and L22 are both more than five times larger than L1. Therefore, the product dimension L21 has little effect on the bending moment value M11 at the contact point between the metal gasket 4 and the left silicone rubber where the fairing is docked. The product dimension L22 has little effect on the bending moment value M12 at the contact point between the metal gasket 4 and the right silicone rubber where the fairing is docked. The relationship between L21, L22 and M11, M12 is a secondary influencing factor of structural mutual extrusion. By ignoring the relationship between L21, L22 and M11, M12, the complex deformation coordination problem is simplified. The entire complex research object is divided at the contact point between the metal gasket 4 and the silicone rubber. It is assumed that the bending moments M11 and M12 are only generated by the mutual extrusion of the structure in the area between the explosive bolt 1 and the contact point. The bending moments M11 and M12 at the contact point then act separately on the left and right sections of the docking frame where the silicone rubber is attached, causing the docking frame to flex and deform. Such an assumption distinguishes the main and secondary influencing factors in the mutual extrusion and deformation coordination of structures, grasps the key points of design, and reduces the design cycle and cost.

[0065] Study the left and right parts of the structure separately. In each part of the structure, according to 11 parameters including L1, L3, L4, H1, H2, H3, H4, H5, H6, W1, and D1, an 11-dimensional matrix can be established, and the corresponding bending moment value M1 is different for different parameter combinations. When the overall structure scheme of a fairing is determined, 9 parameters including L3, L4, H1, H3, H4, H5, H6, W1, and D1 can be determined. Therefore, for a specific fairing sealing scheme, only a two-dimensional matrix with parameters L1 and H2 as variables needs to be established through small-scale tests, and the corresponding relationship between L1, H2, and the bending moment value M1 is established.

[0066] Use the same parameters as the fairing product, L3, L4, H1, H3, H4, H5, H6, W1, and D1, to produce small-scale test pieces. The half-length L2 of the silicone rubber of the test piece is more than 5 times the half-length L1 of the gasket; the elastic modulus E is the equivalent mechanical parameter of the composite fairing docking frame. The docking frame is simplified to an isotropic material, and the in-plane stiffness E of the orthotropic material is calculated by the laminate theory as the material parameter of the isotropic material. The composite layup of the test piece and the composite fairing docking frame is the same, and the parameter E is the same; change L1 by modifying the assembly relationship, and select different thicknesses of H2, and measure the maximum deflection V1 after assembly; calculate the bending moment value M1 through the maximum deflection V1, the half-length L2 of the silicone rubber of the test piece, the docking frame width W1, and the docking frame thickness H3 on the test piece. The calculation formula is as follows:

[0067] I = W1 × H3 3 / 12

[0068] M1 = V1 × E × I / L2 2

[0069] The parameters of the test piece consistent with the fairing product include L3 = 50mm, L4 = 80mm, H1 = 2mm, H3 = 5mm, H4 = 8mm, H5 = 8mm, H6 = 5mm, W1 = 50mm, D1 = 14mm, and E = 90GPa. The data obtained through small-scale tests are shown in Table 2.

[0070] Table 2 Small-scale test data

[0071]

[0072] After completing the small-scale test, carry out product design. According to the flatness of the upper and lower docking frames of the actual product, calculate the thickness H2 of the silicone rubber using formula (1). dH1 is the measured flatness of the upper docking frame 2 of the fairing, and dH1 is measured according to the forming effect of the composite fairing; dH2 is the measured flatness of the lower docking frame 3 of the fairing, and dH2 is measured according to the forming effect of the composite fairing; ΔH2 is the pre-compression amount, and it is specified that ΔH2 = 0.4; H1 is the fairing assembly gap and also the gasket thickness.

[0073] Calculate H2:

[0074] The measured flatness of the upper frame of the fairing docking is dH1 = 0.4, the measured flatness of the lower frame of the fairing docking is dH2 = 0.3, and H2 = H1 + ΔH2 + (dH1 + dH2) = 3.1 mm.

[0075] According to the design requirements of the fairing, determine the deflection limit value V1, and calculate the bending moment values M1 at the contact points of the upper frame 2 and lower frame 3 of the fairing docking with the metal gasket 4 and silicone rubber according to formula (2). The moment of inertia I is the cross-sectional geometric parameter of the composite fairing docking frame, which is consistent with the moment of inertia I of the test piece. Calculate M1:

[0076] Example 1: The design requirement for the fairing is that the deflection limit value V1 is less than 0.2 mm. The width dimension W1 of the composite fairing docking frame is 50 mm, the thickness dimension H3 of the composite fairing docking frame is 5 mm, the equivalent elastic modulus E of the composite material is 90 GPa, L21 = 600 mm, and L22 = 650 mm. Calculate the bending moment values M11 = 26.04 MPa and M12 = 22.19 MPa according to the following formula.

[0077] M1 = V1 × E × I / L2 2

[0078] Calculate L1:

[0079] Example 1: Substitute H2 = 3.1 mm, M11 = 26.04 MPa, and M12 = 22.19 MPa into Table 2. L11 = 56 mm, L12 = 57 mm. All the design schemes of the sealing structure are completed. The product sealing performance meets the requirements, and the size of the metal gasket is reduced to the limit. The product is lighter in weight and is the optimal design scheme.

[0080] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A sealing structure for the butt joint frame of a composite fairing, characterized in that: It includes a fairing docking upper frame, a fairing docking lower frame, a sealing layer, and a number of explosion bolts. The sealing layer is located in the gap between the fairing docking upper frame and the fairing docking lower frame. The fairing docking upper frame and the fairing docking lower frame are connected by the explosion bolts. An explosion bolt box is arranged around the explosion bolts. Gaskets are arranged below the explosion bolt boxes. The gaskets are located in the gap between the fairing docking upper frame and the fairing docking lower frame; The design method of the composite fairing docking frame sealing structure includes the following steps: (1) Conduct small-scale experiments of different sizes to establish a database of L1, H2, and M1; (2) Calculate H2 according to the actual flatness of the docking frame; (3) Calculate the value of M1 according to the limited deflection V1 and the known L2; (4) Substitute the obtained values of H2 and M1 into the database to obtain the corresponding L1; The H2 in step (2) is calculated by the following formula: H2 = H1 + ΔH2 + (dH1 + dH2) (1); The M1 in step (3) is calculated by the following formula: M1 = V1 × E × I / L2 2 (2); The L1 is half of the gasket length or the length on one side of the axis of the explosion bolt. The L2 is half of the sealing layer length. The H2 is the sealing layer thickness. The M1 is the bending moment value at the contact points of the fairing docking upper frame and lower frame with the gasket and the sealing layer. The V1 is the sum of the deflections of the fairing docking upper frame and lower frame; The dH1 is the actual flatness of the fairing docking upper frame. The dH2 is the actual flatness of the fairing docking lower frame. The ΔH2 is the pre-compression amount. The H1 is the gasket thickness; The V1 is the deflection limit value, which is determined by the fairing design requirements. The elastic modulus E is the equivalent mechanical parameter of the composite fairing docking frame. The docking frame is simplified to an isotropic material. The in-plane stiffness E of the orthotropic material is calculated by the laminate theory and used as the material parameter of the isotropic material. The moment of inertia I is the cross-sectional geometric parameter of the composite fairing docking frame.

2. The composite fairing docking frame sealing structure according to claim 1, characterized in that: The gasket is made of metal. The material of the sealing layer is silicone rubber.

3. The composite fairing docking frame sealing structure according to claim 1, wherein: The length of the sealing layer is more than five times the width of the gasket.

4. The design method of the composite fairing docking frame sealing structure according to claim 1, characterized in that: The L2 in step (3) is more than five times the L1.

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