A weapon base structure integrally formed with a carbon fiber boat hull and a design method thereof

Abstract

The present invention discloses a weapon base structure integrally formed with a carbon fiber hull, which comprises a weapon base pre-embedded on a carbon fiber hull deck, and the weapon base is placed in a groove of the carbon fiber hull deck; the weapon base is provided with a bolt hole. The present invention also provides a method for designing a weapon base structure integrally formed with a carbon fiber hull. The present invention solves the difficulty of installing the weapon base on the carbon fiber hull by pre-embedding the weapon base in the carbon fiber hull.

Description

Technical Field

[0001] The present invention belongs to the field of hull structure design in ship engineering, and particularly relates to a weapon pedestal structure integrally formed with a carbon fiber hull and a design method thereof. Background Art

[0002] In order to effectively reduce the weight of the hull and enhance the stealth performance of the unmanned boat, the hull structure adopts carbon fiber composite materials. When weapons such as remote control machine guns work on the hull deck, self-weight static loads and impact loads are applied to the installation pedestal. Therefore, the weapon pedestal generally uses metal materials with high strength and stiffness, such as lightweight aluminum alloy plates, or carbon fiber laminates with a targeted ply design according to the forces on the weapon pedestal. Different from the metal hull, the pedestal cannot be directly installed on the carbon fiber hull by welding. Then how to install the weapon pedestal on the carbon fiber composite hull has become the focus of research. Summary of the Invention

[0003] The purpose of the present invention is to provide a weapon pedestal structure integrally formed with a carbon fiber hull and a design method thereof. The structure and design method solve the installation difficulty of the weapon pedestal on the carbon fiber hull by embedding the weapon pedestal in the carbon fiber hull.

[0004] The technical solution adopted by the present invention is as follows:

[0005] A weapon pedestal structure integrally formed with a carbon fiber hull, which includes a weapon pedestal embedded in the deck of the carbon fiber hull, and the weapon pedestal is placed at a groove on the deck of the carbon fiber hull; bolt holes are provided on the weapon pedestal for facilitating connection with the weapon.

[0006] According to the above scheme, a PVC sandwich layer is provided between the weapon pedestal and the deck of the carbon fiber hull, and the upper and lower surfaces of the PVC sandwich layer and the weapon pedestal are encapsulated with carbon fiber skins to improve the strength and stiffness of the weapon pedestal structure.

[0007] According to the above scheme, the bonding surface between the weapon pedestal and the PVC sandwich layer is bonded with structural adhesive; the weapon pedestal is an aluminum alloy / composite laminate pedestal.

[0008] According to the above scheme, the vertical walls of the groove and the annular decks at both ends of the vertical walls are thickened decks; the thickness of the thickened deck is 1.4 - 1.8 times the thickness of the deck of the carbon fiber hull; to improve the strength and stiffness of the weapon pedestal structure.

[0009] According to the above scheme, the thickness of the PVC sandwich layer is the same as the thickness of the deck of the carbon fiber hull.

[0010] According to the above scheme, the connection between the vertical wall and the annular deck is chamfered circularly (the connection corner area between the vertical wall and the annular deck is chamfered circularly) to reduce the stress concentration phenomenon in the corner area.

[0011] According to the above solution, the radius of the circular chamfer is 40 - 60 mm.

[0012] According to the above solution, a transverse bulkhead is provided under the weapon pedestal, and the lower end of the transverse bulkhead is connected to the keel; a vertical stiffener for the transverse bulkhead is arranged beside the transverse bulkhead, the upper end of the vertical stiffener for the transverse bulkhead is connected to the deck longitudinal girder, and the lower end of the vertical stiffener for the transverse bulkhead is connected to the keel; further increasing the strength and stiffness of the weapon pedestal area.

[0013] According to the above solution, the first bracket is triangular, one side of which is connected to the vertical stiffener of the transverse bulkhead, and the other side is connected to the deck longitudinal girder;

[0014] The second bracket is triangular, one side of which is connected to the vertical stiffener of the transverse bulkhead, and the other side is connected to the keel.

[0015] The present invention also provides a design method for a weapon pedestal structure integrally formed with a carbon fiber hull, and the method includes the following steps:

[0016] (1) Selection of materials for the pedestal embedded parts

[0017] According to the requirements of the performance parameters of the typical weapon installation on the unmanned boat in terms of strength, stiffness, impact / temperature, stress release, etc., and according to the structural characteristics of the carbon fiber hull, select a T700 carbon fiber reinforced PMI resin composite material plate or a high-strength aluminum alloy plate as the embedded weapon pedestal, and conduct targeted optimization design on the carbon fiber layup method of the composite material plate or the thickness of the high-strength aluminum alloy plate, as well as the hull structure form of the pedestal hull, etc., so as to meet the comprehensive requirements of multiple parameters such as strength, stiffness, cost, temperature, etc. of the pedestal and the hull for weapon launch;

[0018] (2) Analysis of the strength and stiffness of the integrated pedestal structure

[0019] 1) Finite element modeling

[0020] For the composite material weapon pedestal structure solution, conduct finite element modeling analysis according to the actual size of the pedestal, and the total number of nodes is not less than 46,000; use general finite element calculation software for mesh generation and finite element analysis, and conduct extended analysis on the special composite materials and strengthened models involved therein;

[0021] 2) Application of pedestal loads and boundary conditions

[0022] After the finite element model of the pedestal is established, it is necessary to apply pedestal loads such as wave loads, sway inertia forces, splash water pressures, and weapon launch impacts, and set corresponding displacement boundary conditions to lay a foundation for finite element calculation;

[0023] 3) Calculation and solution

[0024] Based on the finite element model and the set boundary conditions, carry out the dynamic analysis of the pedestal structure;

[0025] 4) Strength and stiffness evaluation of the integrated pedestal structure

[0026] Analyze the finite element calculation results, evaluate the stiffness and strength of the integrated pedestal structure. If the evaluation results show that the pedestal and its embedded parts meet the design requirements, complete the finite element analysis and calculation of this part; otherwise, re-iterate the model parameters and modify the design scheme;

[0027] (3) Integrated molding process design of the pedestal embedded parts

[0028] According to the design scheme of the weapon pedestal structure, design the integrated molding process of the weapon pedestal embedding. Comprehensively consider the influence of factors such as temperature, humidity, air pressure on the material and the release of structural stress; the upper and lower skins of the weapon pedestal embedded parts are formed by using T700 carbon fiber prepreg, the foam sandwich uses lightweight, high-strength and high-temperature-resistant PMI foam, and the foam core and the embedded parts are connected to the upper and lower skins by using structural adhesive film;

[0029] The specific molding process flow is divided into six steps: mold preparation, raw material cutting, product laying, product curing, product demolding and machining; the mold needs to be customized according to the molding structure characteristics, and the mold laying surface needs to be wiped with a special mold release agent in advance; before raw material cutting, a product laying cutting diagram needs to be made, and the made cutting diagram is imported into the automatic cutting machine; lay the prepreg in the mold according to the ply design angle; after laying, use the autoclave high-temperature curing molding process to complete the curing and molding of the embedded pedestal; then, according to the installation requirements of the weapon equipment, machine the installation holes of the cured product through machining.

[0030] The beneficial effects of the present invention are as follows:

[0031] By embedding the weapon pedestal in the carbon fiber hull deck (the carbon fiber hull deck and the weapon pedestal are manufactured by one-time molding), the problem that the weapon pedestal cannot be directly installed on the carbon fiber hull by welding is solved;

[0032] Adopt the sunken carbon fiber hull weapon pedestal structure design, which ensures that the weapon pedestal structure has good strength and stiffness and can better meet the requirements of weapon combat use;

[0033] The weapon equipment pedestal designed by this design method is integrally molded with the hull. The pedestal does not need to be connected to the carbon fiber hull by other means such as welding. Through the optimization design and mechanical analysis of the pedestal structure, it is ensured that it has good strength and stiffness and can better meet the requirements of weapon combat use. Description of the drawings

[0034] The present invention will be further described below in conjunction with the accompanying drawings and embodiments. In the drawings:

[0035] Figure 1 is a schematic plan view of the weapon base structure integrally formed with the carbon fiber hull;

[0036] Figure 2 is Figure 1 the sectional view taken along line A-A in

[0037] Figure 3 is Figure 2 the enlarged view of A1 in

[0038] In the figure: 1, weapon base; 2, thickened deck; 2.1, vertical wall; 2.2, annular deck; 3, transverse bulkhead; 4, carbon fiber hull deck; 5, deck longitudinal girder; 6, vertical stiffener of transverse bulkhead; 7.1, first bracket; 7.2, second bracket; 8, keel; 9, carbon fiber skin; 10, PVC sandwich layer; 11, groove; 12, bolt hole; 13, structural adhesive; 14, circular chamfer. Detailed implementation manners

[0039] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0040] A design method for a weapon base structure integrally formed with a carbon fiber hull, the method comprising the following steps:

[0041] (1) Material selection of the weapon base on the carbon fiber hull deck

[0042] According to the performance parameter requirements of the typical weapon installation on the unmanned boat for strength, stiffness, impact / temperature and stress release, as well as the carbon fiber hull structure characteristics, select the T700 carbon fiber reinforced PMI resin composite material plate or the high-strength aluminum alloy plate as the weapon base material on the carbon fiber hull deck; through mechanical analysis, optimize the ply lay-up method of the weapon base on the carbon fiber hull deck or the thickness of the high-strength aluminum alloy plate, as well as the hull structure form of the base hull, so as to meet the comprehensive requirements of the weapon launch for the strength, stiffness, cost and temperature parameters of the base and the hull;

[0043] (2) Strength and stiffness analysis of the integrated base structure

[0044] 1) Finite element modeling

[0045] For the structure of the weapon base on the carbon fiber hull deck, carry out finite element modeling analysis according to the actual size of the base, and the total number of nodes is not less than 46000;

[0046] 2) Apply the base load and boundary conditions

[0047] After establishing the finite element model of the base, apply the base load and set the corresponding displacement boundary conditions to lay the foundation for finite element calculation; the base load includes wave load, sway inertia force, splash water pressure, and weapon launch impact;

[0048] 3) Calculate and solve

[0049] Conduct dynamic analysis of the base structure according to the finite element model and the set boundary conditions;

[0050] 4) Evaluate the strength and stiffness of the integrated base structure

[0051] Analyze the finite element calculation results to evaluate the stiffness and strength of the integrated base structure. If the evaluation results show that the base and its embedded parts meet the design requirements, the finite element analysis and calculation of this part are completed; otherwise, iterate the model parameters and modify the design scheme;

[0052] (3) Design of the integrated forming process for the base embedded parts

[0053] Design the integrated forming process for the base embedded parts according to the structural design scheme, comprehensively considering the influence of factors such as temperature, humidity, air pressure on materials, and the release of structural stress.

[0054] In this method, use ABAQUS software to establish a finite element model. The main difficulty is that ABAQUS software cannot perform ply design for beam elements, and the predefined beam sections in ABAQUS software do not have the cross-section form of the hat-shaped rib, which is the stiffener used for the carbon fiber hull. Therefore, first use a two-dimensional deformable shell to establish the cross-section shape according to the actual size of the hat-shaped rib, then perform virtual cutting according to the number of ply layers, create a local coordinate system, assign materials and directions to each layer respectively according to the ply direction, select the WARP2D4 element for mesh division, create a Job and submit the analysis. The generated BSP file after the analysis includes the main characteristics of the cross-section. Write the BSP file into the INP file for the integrated forming base analysis for calculation.

[0055] For the finite element model of the carbon fiber hull plate and the embedded parts, use the shell elements provided by ABAUS software, and use three-dimensional solid elements for the foam core. Use Tie connections between the hat-shaped ribs, upper and lower skins, foam core materials, and base embedded parts. Secondly, since the force on the base during weapon launch is an impact load, it is necessary to use the dynamic calculation and analysis module to analyze the base, fit the weapon launch force into a function that changes with time and apply it to the base. After the calculation is completed, extract the calculation results of the base stress and strain changing with time to evaluate and analyze whether the structural design of the base and the hull meets the requirements.

[0056] See Figures 1 - 3, A weapon base structure integrally formed with a carbon fiber hull, which includes an aluminum alloy / composite laminate weapon base 1 embedded in the carbon fiber hull deck 4 (the weapon base 1 is embedded in the carbon fiber hull deck 4). To meet the requirements of the weapon firing range and reduce the weight and center of gravity of the hull, the weapon base 1 is placed at the groove 11 of the carbon fiber hull deck 4. The weapon base 1 is provided with bolt holes 12 for facilitating connection with the weapon. To improve the strength and stiffness of the weapon base structure, a PVC sandwich layer 10 is provided between the weapon base 1 and the carbon fiber hull deck 4, and structural adhesive 13 is used for bonding at the connection surface between the weapon base 1 and the PVC sandwich layer 10; the upper and lower surfaces of the PVC sandwich layer 10 and the weapon base 1 are encapsulated with carbon fiber skins 9.

[0057] To further ensure that the carbon fiber hull deck 4 has sufficient strength at the sinking turning point, the vertical wall 2.1 of the groove 11 and the annular decks 2.2 at both ends of the vertical wall 2.1 are thickened decks 2; to reduce the stress concentration level in the corner area formed by the local sinking of the carbon fiber hull deck 4, a circular chamfer 14 is provided at the connection between the vertical wall 2.1 and the annular deck 2.2, and the radius of the circular chamfer is 50 mm; the thickness of the thickened deck 2 is 1.6 times the thickness of the carbon fiber hull deck 4; the thickness of the PVC sandwich layer 10 is the same as the thickness of the carbon fiber hull deck 4.

[0058] To further improve the strength and stiffness of the weapon base structure, a transverse bulkhead 3 is provided under the weapon base 1, and the lower end of the transverse bulkhead 3 is connected to the keel 8; a vertical stiffener 6 for the transverse bulkhead is provided beside the transverse bulkhead 3, and the upper end of the vertical stiffener 6 for the transverse bulkhead is connected to the deck girder 5 (the deck girder 5 is an original structure of the hull), and the lower end of the vertical stiffener 6 for the transverse bulkhead is connected to the keel 8. The first bracket 7.1 is triangular, one side of which is connected to the vertical stiffener 6 for the transverse bulkhead, and the other side is connected to the deck girder 5; the second bracket 7.2 is triangular, one side of which is connected to the vertical stiffener 6 for the transverse bulkhead, and the other side is connected to the keel 8.

[0059] It should be understood that for those of ordinary skill in the art, improvements or transformations can be made according to the above description, and all such improvements and transformations should fall within the protection scope of the appended claims of the present invention.

Claims

1. A design method for a weapon base structure integrally formed with a carbon fiber boat body, characterized in that: The weapon base structure integrally formed with the carbon fiber hull comprises a weapon base pre-buried on the carbon fiber hull deck, and the weapon base is placed in a groove of the carbon fiber hull deck; a bolt hole is provided on the weapon base; a PVC sandwich layer is provided between the weapon base and the carbon fiber hull deck, and the upper and lower surfaces of the PVC sandwich layer and the weapon base are encapsulated with carbon fiber skins; The method adopts the following steps: (1) Material selection for weapon base on carbon fiber hull deck According to the performance parameter requirements of strength, stiffness, impact, temperature, and stress release of typical weapons installed on unmanned boats, as well as the structural characteristics of the carbon fiber hull, T700 carbon fiber reinforced PMI resin composite material plates or high-strength aluminum alloy plates are selected as the weapon base materials on the carbon fiber hull deck; through mechanical analysis, the plying method of the weapon base on the carbon fiber hull deck or the thickness of the high-strength aluminum alloy plate, as well as the base hull structure are optimized and designed to meet the comprehensive requirements of the strength, stiffness, cost, and temperature parameters of the base and hull for weapon launch; (2) Analysis of the strength and stiffness of the integrated base structure 1) Finite element modeling For the structure of the weapon base on the carbon fiber hull deck, finite element modeling analysis was carried out according to the actual size of the base, with a total number of nodes not less than 46,000; 2) Apply base load and boundary conditions After the finite element model of the foundation is established, the foundation load is applied and the corresponding displacement boundary conditions are set to lay the foundation for finite element calculation; 3) Calculation and solution According to the finite element model and the set boundary conditions, the foundation structure dynamics analysis is carried out; 4) Integrated base structure strength and stiffness assessment Analyze the finite element calculation results and evaluate the rigidity and strength of the integrated base structure. If the evaluation results show that the base and its embedded parts meet the design requirements, complete the finite element analysis calculation of this part. Otherwise, re-iterate the model parameters and modify the design plan. (3) Integrated molding process design of base embedded parts According to the structural design plan, the integrated molding process of the embedded parts of the base is designed, and the influence of temperature, humidity, air pressure and structural stress release factors on the material are comprehensively considered.

2. The method for designing a weapon base structure integrally formed with a carbon fiber boat body according to claim 1, characterized in that: The base loads include wave loads, rocking inertia force, splash water pressure, and weapon launch impact.

3. The method for designing a weapon base structure integrally formed with a carbon fiber boat body according to claim 1, characterized in that: The vertical wall of the groove and the annular decks at both ends of the vertical wall are thickened decks.

4. The method for designing a weapon base structure integrally formed with a carbon fiber boat body according to claim 3, characterized in that: The thickness of the thickened deck is 1.4 to 1.8 times the thickness of the carbon fiber hull deck.

5. The method for designing a weapon base structure integrally formed with a carbon fiber boat body according to claim 3, characterized in that: The connection between the vertical wall and the annular deck is rounded and chamfered.

6. The method for designing a weapon base structure integrally formed with a carbon fiber boat body according to claim 5, characterized in that: The radius of the circular chamfer is 40-60 mm.

7. The method for designing a weapon base structure integrally formed with a carbon fiber boat body according to claim 1, characterized in that: A transverse bulkhead is provided under the weapon base, and the lower end of the transverse bulkhead is connected to the keel.

8. The method for designing a weapon base structure integrally formed with a carbon fiber boat body according to claim 7, characterized in that: A transverse bulkhead vertical stiffener is arranged beside the transverse bulkhead, the upper end of the transverse bulkhead vertical stiffener is connected to the deck longitudinal girder, and the lower end of the transverse bulkhead vertical stiffener is connected to the keel.

9. The method for designing a weapon base structure integrally formed with a carbon fiber boat body according to claim 8, characterized in that: The first bracket is triangular in shape, one side of which is connected to the vertical stiffener of the transverse bulkhead and the other side is connected to the longitudinal girder of the deck; The second bracket is triangular in shape, one side of which is connected to the vertical stiffener of the transverse bulkhead and the other side is connected to the keel.

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