Deep sea composite material pressure-resistant cylinder and reinforcement method

Abstract

The invention provides a deep sea composite material pressure-resistant cylinder and a reinforcement method. A cylinder body of the pressure-resistant cylinder is provided with paired annular reinforcement bodies I and crossed reinforcement bodies I; the annular rib body I is of a radial rigid supporting circular ring structure, and the crossed rib body I is of a two-inclined-ring structure crossed in the middle of the cylinder body. The crossed rib body I is located in the center of the pressure-resistant cylinder body, the annular rib bodies I are arranged on the two sides of the crossed rib body, the centers of the two annular rib bodies I are coaxial with the center of the crossed rib body I, and the distances from the two annular rib bodies I to the center of the crossed rib body I are equal. According to the deep sea composite material pressure-resistant cylinder and the reinforcement method, the problems that in the prior art, a pressure-resistant cylinder is large in design mass, low in bearing efficiency and the like are solved.

Description

Technical Field

[0001] The invention belongs to the technical field of underwater vehicles, and in particular relates to a deep-sea composite material pressure-resistant tube and a reinforcement method. Background Art

[0002] As a key technical equipment for marine scientific exploration and development, underwater vehicles have attracted widespread attention from countries around the world due to their unique advantages and broad application prospects. As the core part of the underwater vehicle structure, the pressure cylinder structure undertakes the arduous task of providing a safe watertight space and overall buoyancy reserve for the system equipment, and ensuring the normal operation of the main equipment. In traditional technical designs, the pressure cylinder is cylindrical, and its cylinder surface, as the main pressure-resistant structure, is required to have a certain compressive strength and stiffness. However, due to the small safety factor of the stiffness of the cylindrical pressure cylinder, it is prone to buckling or instability failure. In addition, composite materials have gradually become the material of choice for underwater vehicle pressure cylinders due to their excellent mechanical properties and outstanding marine corrosion resistance.

[0003] When working in the deep sea, traditional underwater vehicles usually choose to increase the thickness of the cylinder or set up multiple annular ribs to improve the overall structural rigidity of the pressure cylinder. However, these two methods will greatly increase the mass of the pressure cylinder itself, thereby increasing the energy consumption of the underwater vehicle when working, while reducing the amount of payload carried, and cannot further meet the development needs of underwater vehicle technology for deep-sea exploration. At the same time, composite materials are typical anisotropic materials, and their mechanical properties are completely different from those of metal materials. The reinforcement method of pressure cylinders made of traditional metal materials is not suitable for composite pressure cylinder structures. It is necessary to find other efficient and suitable reinforcement methods for composite pressure cylinders. Summary of the invention

[0004] In order to overcome the deficiencies in the prior art, the inventors have conducted intensive research and provided a deep-sea composite pressure tube and reinforcement method to solve the problems of large design mass and low load-bearing efficiency of the pressure tube in the prior art.

[0005] The technical solution provided by the present invention is as follows:

[0006] In a first aspect, a deep-sea composite pressure-resistant cylinder is provided, wherein the cylinder body of the pressure-resistant cylinder has a pair of annular ribs I and cross ribs I;

[0007] The annular ribs I are circular ring structures with radial rigid support, and the cross ribs I are two oblique ring structures crossing in the middle of the cylinder; the cross ribs I are located in the middle of the pressure-resistant cylinder, and the annular ribs I are arranged on both sides of the cross ribs, the centers of the two annular ribs I are coaxial with the center of the cross ribs I, and the center distances from the two annular ribs I to the cross ribs I are equal.

[0008] In a second aspect, a method for reinforcing a deep-sea composite pressure-resistant tube comprises: forming an annular reinforcement body I and a cross reinforcement body I on a tube body of the pressure-resistant tube;

[0009] The annular ribs I are circular ring structures with radial rigid support, and the cross ribs I are two oblique ring structures crossing in the middle of the cylinder; the cross ribs I are located in the middle of the pressure-resistant cylinder, and the annular ribs I are arranged on both sides of the cross ribs, the centers of the two annular ribs I are coaxial with the center of the cross ribs I, and the center distances from the two annular ribs I to the cross ribs I are equal.

[0010] A deep-sea composite material pressure-resistant cylinder and reinforcement method provided by the present invention have the following beneficial effects:

[0011] (1) The present invention provides a deep-sea composite pressure tube and a reinforcement method. The annular reinforcement body and the cross reinforcement body are used as rigid support parts. The mixed reinforcement design of the two has a synergistic effect. The annular reinforcement enhances the pressure resistance of the pressure tube. At the same time, the cross reinforcement provides stronger lateral and longitudinal support, which can effectively prevent the buckling of the underwater vehicle pressure tube.

[0012] (2) The present invention provides a deep-sea composite pressure-resistant tube and reinforcement method. The mixed reinforcement method can achieve precise control of the tube performance, reduce the risk of failure due to structural defects or unstable material properties, facilitate subsequent maintenance and repair work, reduce the cost and risk of deep-sea operations, improve the durability of the pressure-resistant tube, and extend the service life of the pressure-resistant tube;

[0013] (3) Compared with simply thickening the wall thickness of the pressure-resistant tube, the deep-sea composite pressure-resistant tube and reinforcement method provided by the present invention have a smaller increased structural mass and a higher structural utilization efficiency, thereby achieving the purpose of lightweight design. This enables the underwater vehicle to fully ensure its own structural safety while improving its own payload carrying capacity and endurance when working in deep water. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 A three-dimensional diagram of a deep-sea composite pressure-resistant cylinder according to the present invention;

[0015] Figure 2 It is a cross-sectional view of the deep-sea composite pressure-resistant cylinder of the present invention;

[0016] Figure 3 (a) is the buckling mode of the reinforced pressure tube;

[0017] Figure 3 (b) is the buckling mode section of the reinforced pressure tube;

[0018] Figure 3 (c) is the buckling mode of the unreinforced pressure tube;

[0019] Figure 3 (d) is the buckling mode section of the unreinforced pressure tube;

[0020] Figure 3 (e) is the stress cloud diagram of the outermost layer of the circumferential paving surface of the reinforced pressure tube;

[0021] Figure 3 (f) is the stress cloud diagram of the outermost layer of the axial ply surface of the reinforced pressure tube;

[0022] Figure 3 (g) is the stress cloud diagram of the outermost layer of the circumferential ply of the unreinforced pressure tube;

[0023] Figure 3 (h) is the stress cloud diagram of the outermost layer of the axial layer of the unreinforced pressure tube;

[0024] Figure 3 (i) is the strain contour diagram of the reinforced pressure tube;

[0025] Figure 3 (j) is the strain contour section of the reinforced pressure tube;

[0026] Figure 3 (k) is the strain contour diagram of the unreinforced pressure tube;

[0027] Figure 3 (l) is the strain contour section of the unreinforced pressure tube;

[0028] Figure 3 (m) is the buckling mode simulation of the thickened pressure tube with equal mass;

[0029] Figure 3 (n) is the buckling mode simulation of the thickened pressure tube with equal mass;

[0030] Figure 4 It is a cross-sectional view of a pressure tube with annular reinforcement II;

[0031] Figure 5 It is a cross-sectional view of the pressure tube with cross reinforcement II. DETAILED DESCRIPTION

[0032] The following detailed description of the present invention will make the features and advantages of the present invention more clear and explicit.

[0033] The word “exemplary” is used exclusively herein to mean “serving as an example, example, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.

[0034] In order to solve the problems that the shell thickness of the underwater vehicle pressure cylinder needs to be increased as the water depth increases, which leads to a significant increase in its own mass, resulting in a decrease in its own endurance and a reduction in the amount of effective load carried, etc., the present invention provides a deep-sea composite pressure cylinder.

[0035] like Figure 1 and Figure 2 As shown, the cylinder 1 of the pressure-resistant cylinder has a pair of annular ribs I 2 and cross ribs I 3; the annular ribs I 2 are circular ring structures with radial rigid support, and the cross ribs I 3 are two oblique ring structures crossing in the middle of the cylinder; the cross ribs I 3 are located in the middle of the cylinder 1 of the pressure-resistant cylinder, the annular ribs I 2 are arranged on both sides of the cross ribs I 3, the centers of the two annular ribs I are coaxial with the center of the cross ribs I, and the center distances from the two annular ribs I 2 to the cross ribs I 3 are equal, and the annular ribs I 2 and the cross ribs I 3 are used as integral reinforcement parts to provide rigid support for the composite pressure-resistant cylinder. This reinforcement method has the advantages of light weight, high rigidity, and high structural efficiency, and can effectively cope with high pressure conditions in the deep sea.

[0036] In a preferred embodiment, the annular rib body I 2 is arranged on the outer wall of the pressure-resistant cylinder body 1 to form an annular rib body protruding radially outward; the cross rib body I 3 is arranged on the inner wall of the pressure-resistant cylinder body 1 to form an oblique annular cross rib body protruding radially inward.

[0037] In a preferred embodiment, when the pressure-resistant cylinder has only two annular ribs I and one cross rib I on its body, the axial span of the cross rib I is 20% to 60% of the length of the pressure-resistant cylinder body; the length of the annular rib I from the end of the pressure-resistant cylinder is 20% to 40% of the length of the pressure-resistant cylinder body.

[0038] In a preferred embodiment, based on the strength and stiffness matching design, the annular rib body 1 and the cross rib body 1 are made of the same composite material as the pressure-resistant cylinder body, preferably using an integrated molding process, that is, the cylinder body 1 and the annular rib body 1 2 and the cross rib body 1 3 are molded simultaneously. The pressure-resistant cylinder body, the annular rib body 1 and the cross rib body 1 are all made of carbon fiber composite materials, which have the advantages of high specific strength, corrosion resistance, low density, etc.

[0039] When underwater vehicles work in the deep sea, they face great seawater pressure and seawater corrosion. The pressure-resistant tube reinforcement method in the present invention can effectively improve the ability of the pressure-resistant tube to resist deformation caused by deep-sea pressure, and effectively utilize limited space and less mass, effectively avoiding the problem of substantial increase in mass and energy consumption due to the need to thicken the tube in the deep sea, and this reinforcement method can effectively disperse the concentrated deformation and stress in the middle of the shell.

[0040] The pressure tube structure of the present invention is numerically simulated using ABAQUS finite element simulation software. The axial span of the cross reinforcement body I is 23% of the length of the pressure tube body; the length of the annular reinforcement body I from the end of the pressure tube is 34% of the length of the pressure tube body. Figure 3 (a) and Figure 3 (b) is the first-order buckling mode cloud diagram of the pressure tube structure using the reinforcement method of the present invention. The buckling characteristic value of the structure is 69.045MPa. Figure 3 (c) and Figure 3 (d) is the first-order buckling mode cloud diagram of the pressure tube without annular reinforcement and cross reinforcement, and its buckling characteristic value is 46.722MPa. The reinforcement method of the present invention effectively improves the critical buckling pressure of the pressure tube structure.

[0041] The stress and strain of the pressure tube structure of the present invention and the unreinforced pressure tube structure under specific working conditions are compared and analyzed as follows:

[0042] stress: Figure 3 (e) and Figure 3 (f) are respectively the stress distribution cloud diagrams of the outermost circumferential layer and the outermost axial layer of the reinforced pressure tube structure of the present invention, Figure 3 (g) and Figure 3 (h) are respectively the stress distribution cloud diagrams of the circumferential outermost layer and the axial outermost layer of the unreinforced pressure tube structure. From the stress results, the reinforced structure of the present invention effectively reduces the maximum stress of the composite material plywood layer of the pressure hull (in the legend of the stress cloud diagram, the maximum stress of the axial plywood layer is greater than 1200MPa due to the contact between the pressure tube and the end cover, which has nothing to do with the effect of the structure of this embodiment and can be ignored).

[0043] strain: Figure 3 (i) and Figure 3 (j) is a cloud diagram of radial deformation of the pressure-resistant cylinder structure of the present invention under specific working conditions. Figure 3 (k) and Figure 3 (l) is the radial deformation cloud diagram of the unreinforced pressure tube structure under specific working conditions. From the deformation results, due to the existence of the reinforced structure, the overall deformation position of the pressure tube is regulated, so that the deformation is mainly concentrated in the middle part, and the deformation in other positions is greatly reduced.

[0044] In order to highlight the effect of the present invention, a structure with the same mass as the present invention but only with increased cylinder thickness is used as a comparative case. Figure 3 (m) and Figure 3 (n) is the first-order buckling mode cloud diagram of the comparative case, and the buckling eigenvalue of the structure is 54.71MPa.

[0045] Figure 1 and Figure 2In the embodiment, the cylinder of the pressure-resistant cylinder has only two annular ribs I and one cross rib I. For an extra-long pressure-resistant cylinder, on the cylinder of the pressure-resistant cylinder, symmetrically distributed annular ribs II4 and cross ribs II 5 may be provided on the axially outer sides of the two annular ribs I; the annular ribs II 4 are provided on the outer wall of the cylinder of the pressure-resistant cylinder to form an annular rib that protrudes radially outward, and the cross ribs II 5 are provided on the inner wall of the cylinder of the pressure-resistant cylinder to form an oblique annular cross rib that protrudes radially inward.

[0046] Similarly, the annular ribs II 4 and the cross ribs II 5 are made of the same composite material as the pressure-resistant cylinder body, preferably using an integrated molding process, that is, the cylinder body 1 and the annular ribs II 4 and the cross ribs II 5 are molded at the same time.

[0047] The present invention provides a deep-sea composite pressure tube and reinforcement method. The annular reinforcement body and the cross reinforcement body are used as rigid support parts. The mixed reinforcement design of the two has a synergistic effect. The annular reinforcement enhances the pressure resistance of the pressure tube. At the same time, the cross reinforcement provides stronger lateral and longitudinal support, which can effectively prevent the buckling of the underwater vehicle pressure tube. Compared with the single thickening of the pressure tube wall, the increased structural mass is smaller, the utilization efficiency of the structure is higher, and the lightweight design purpose can be achieved. This allows the underwater vehicle to fully ensure its own structural safety when working in deep water, and to improve its own payload carrying capacity and endurance.

[0048] The present invention has been described in detail above in conjunction with specific implementations and exemplary examples, but these descriptions cannot be understood as limiting the present invention. Those skilled in the art understand that, without departing from the spirit and scope of the present invention, a variety of equivalent substitutions, modifications or improvements may be made to the technical solution of the present invention and its implementation methods, all of which fall within the scope of the present invention. The scope of protection of the present invention shall be subject to the attached claims.

[0049] The contents not described in detail in the specification of the present invention belong to the common knowledge of those skilled in the art.

Claims

1. A deep-sea composite pressure-resistant cylinder, characterized in that: The cylinder body of the pressure-resistant cylinder is provided with a pair of annular ribs I and cross ribs I; The annular ribs I are circular ring structures with radial rigid support, and the cross ribs I are two oblique ring structures crossing in the middle of the cylinder; the cross ribs I are located in the middle of the pressure-resistant cylinder, and the annular ribs I are arranged on both sides of the cross ribs, the centers of the two annular ribs I are coaxial with the center of the cross ribs I, and the center distances from the two annular ribs I to the cross ribs I are equal.

2. The deep-sea composite pressure-resistant cylinder according to claim 1, characterized in that: The annular rib body I is arranged on the outer wall of the pressure-resistant cylinder to form an annular rib body protruding radially outward.

3. The deep-sea composite pressure-resistant cylinder according to claim 1, characterized in that: The cross ribs I are arranged on the inner wall of the pressure-resistant cylinder to form an oblique annular cross rib that protrudes radially inward.

4. The deep-sea composite pressure-resistant cylinder according to claim 1, characterized in that: The annular rib body I and the cross rib body I are made of the same composite material as the pressure-resistant cylinder body. Preferably, the pressure-resistant cylinder body, the annular rib body I and the cross rib body I are simultaneously formed using an integrated molding process.

5. The deep-sea composite pressure-resistant cylinder according to claim 1, characterized in that: Axially outer sides of the two annular ribs I are also provided with symmetrically distributed annular ribs II and / or cross ribs II. The structure of the annular ribs II is the same as that of the annular ribs I, and the structure of the cross ribs II is the same as that of the cross ribs I.

6. A method for reinforcing a deep-sea composite pressure-resistant tube, characterized in that: include: Forming an annular reinforcement body I and a cross reinforcement body I on the cylinder body of the pressure-resistant cylinder; The annular ribs I are circular ring structures with radial rigid support, and the cross ribs I are two oblique ring structures crossing in the middle of the cylinder; the cross ribs I are located in the middle of the pressure-resistant cylinder, and the annular ribs I are arranged on both sides of the cross ribs, the centers of the two annular ribs I are coaxial with the center of the cross ribs I, and the center distances from the two annular ribs I to the cross ribs I are equal.

7. The reinforcement method of deep-sea composite pressure-resistant tube according to claim 6, characterized in that: Also includes: The annular rib body I is arranged on the outside of the pressure-resistant cylinder body to form an annular rib body protruding radially outward; the cross rib body I is arranged on the inside of the pressure-resistant cylinder body to form an oblique annular cross rib body protruding radially inward.

8. The reinforcement method of deep-sea composite pressure-resistant tube according to claim 6, characterized in that: Also includes: Axially outside the two annular ribs I, symmetrically distributed annular ribs II and / or cross ribs II are also provided. The structure of the annular ribs II is the same as that of the annular ribs I, and the structure of the cross ribs II is the same as that of the cross ribs I.

9. The reinforcement method of deep-sea composite pressure-resistant tube according to claim 8, characterized in that: The annular rib body I, annular rib body II, cross rib body I and cross rib body II are made of the same composite material as the pressure-resistant cylinder body.

10. The reinforcement method of deep-sea composite pressure-resistant tube according to claim 8, characterized in that: The pressure-resistant cylinder body, annular rib body I, annular rib body II, cross rib body I and cross rib body II are simultaneously formed by an integrated forming process.

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