Shared mooring design method and system for floating aquaculture cage groups

Abstract

The present application belongs to the technical field of aquaculture cage groups, and specifically relates to a shared mooring design method and system for a floating aquaculture cage group, including a mooring array, a plurality of outer anchoring foundations, and a plurality of outer mooring cables; the advantage is that adjacent floating aquaculture cages use a "buoy-mooring cable-anchoring foundation" mooring method. Compared with the catenary mooring method, the "buoy-mooring cable-anchoring foundation" mooring method has a small mooring radius, a large horizontal restoring force, and a small vertical load, which can increase the cage deployment density and improve the utilization rate of the sea.

Description

Technical Field

[0001] The present application relates to a floating aquaculture cage group, and specifically to a shared mooring design method and system for a floating aquaculture cage group. Background Art

[0002] The large number of piles driven into the sea for fixed aquaculture cages will cause permanent damage to the sea area; after the self-elevating aquaculture cages have been piled for a long time at sea, it will be difficult to remove the piles, and they will face the same problems as fixed platforms or fences. Relatively speaking, bottom-seated aquaculture cages have less damage to the environment, and floating aquaculture cages have the least damage to the environment. However, in order to resist marine environmental loads such as wind, waves and currents, aquaculture cages need to be equipped with a mooring system to ensure the safety of floating aquaculture cages.

[0003] At present, with the improvement of the equipment level of aquaculture facilities, marine aquaculture is moving towards the deep sea. The deployment of floating aquaculture cage groups in open waters and the development of mooring systems suitable for floating aquaculture cage groups are the key to promoting the high-quality development of deep-sea aquaculture. For aquaculture areas of a specific area, if each cage adopts a single-point mooring, in order to avoid collisions between cages in the floating aquaculture cage group, the spacing between cages will inevitably increase, the number of cages will decrease, and the aquaculture output in the sea area will decrease. If each cage adopts multi-point mooring, it will also lead to an increase in the spacing between cages, a decrease in the number of cages, and a decrease in aquaculture output in the sea area. Therefore, in order to improve the efficiency of sea use and vigorously develop floating aquaculture cage groups, it is urgent to propose new mooring technologies suitable for floating aquaculture cage groups. Summary of the invention

[0004] Based on the above problems, the purpose of the present invention is to provide a shared mooring design method and system for a floating aquaculture cage group, and its technical solution is:

[0005] A shared mooring design method for a floating aquaculture cage group, comprising:

[0006] For internal mooring lines , get the internal mooring line The horizontal and vertical distances between the two end points, through the internal mooring line The catenary equation is used to calculate the internal mooring cable the tension at the fairlead and the horizontal component of tension;

[0007] For the internal anchor foundation, the net load on the internal anchor foundation is calculated based on the force on the float, and the parameters of the internal anchor foundation are obtained based on the net load on the internal anchor foundation;

[0008] For the outer mooring cable, based on the balance law of a single cage force, calculate the horizontal component of the tension of the outer mooring cable at the chain guide hole, obtain the horizontal distance between the two end points of the outer mooring cable, and calculate the tension of the outer mooring cable at the chain guide hole according to the catenary equation of the outer mooring cable;

[0009] For the outer anchor foundation, the net load on the outer anchor foundation is obtained, and then the parameters of the outer anchor foundation are obtained.

[0010] Preferably, internal mooring lines The parameter calculation steps are as follows:

[0011] Step 1: Input the internal mooring line The basic parameters, including the internal mooring lines The initial length , Internal mooring lines Weight in water , Internal mooring lines The elastic modulus , Internal mooring lines Cross-sectional area ;

[0012] Step 2: Get the internal mooring line The endpoint coordinates of the internal mooring line Horizontal distance ; Internal mooring lines The catenary equation is calculated as follows:

[0013] ;

[0014] Step 3: Calculate the internal mooring cable by using the catenary equation Horizontal component of tension at the fairlead .

[0015] Preferably, the steps for calculating the internal anchor foundation parameters are as follows:

[0016] Step 1: Input the buoyancy of the float ,gravity , Internal mooring lines The initial length , Internal mooring lines Weight in water ;

[0017] Step 2: The floating ball is in a balanced state, and the vertical force it is subjected to includes buoyancy. ,gravity and an internal mooring line Tension According to the force balance relationship, the internal mooring cable is calculated The tension at the connection with the float , the calculation formula is as follows:

[0018] ;

[0019] Step 3: Due to the internal mooring line The two ends are connected to the floating ball and the internal anchor foundation respectively, so the net load on the internal anchor foundation is Equal to the internal mooring line Tension Minus the internal mooring lines Weight in water, based on the net load on the internal anchor foundation , get the parameters of the internal anchor foundation, The calculation formula is as follows:

[0020] .

[0021] Preferably, the outer mooring line related parameters are calculated as follows:

[0022] Step 1: Input the basic parameters of the outer mooring cable, including the weight of the outer mooring cable in water. , elastic modulus of the outer mooring line , cross-sectional area of ​​the outer mooring line ;

[0023] Step 2: The buoy or floating aquaculture cage connected to the outer mooring cable is in a balanced state, and the horizontal force it receives includes the internal mooring cable connected to the buoy or floating aquaculture cage. The horizontal component of the tension at the chain eye and an outer mooring line The horizontal component of the tension at the chain guide hole is calculated according to the law of force balance: , the calculation formula is as follows:

[0024] ;

[0025] The third step is to obtain the coordinates of the outer mooring cable endpoints. , , get the horizontal distance from the outer mooring cable fairlead to the outer anchor foundation and vertical distance , the tension of the outer mooring cable at the chain guide hole The calculation formula is as follows:

[0026] ;

[0027] Length of outer mooring line in water The calculation formula is as follows:

[0028] .

[0029] A shared mooring system for a group of floating aquaculture cages, comprising a mooring array, a plurality of outer anchoring foundations, and a plurality of outer mooring cables; wherein:

[0030] The mooring array includes a floating aquaculture cage, a buoy, an internal anchoring foundation, an internal mooring cable, , Internal mooring lines The floating aquaculture cage is located on the sea surface and is provided with a number of chain guide holes, which are evenly distributed around the horizontal circumference of the floating aquaculture cage;

[0031] The buoy is arranged in the seawater, and is provided with the same number of chain guide holes as the chain guide holes of the floating aquaculture cage, and the chain guide holes are evenly distributed around the horizontal circumference of the buoy; the buoy is connected to the floating cage by the internal mooring cable. being tensionedly connected to the floating aquaculture cage;

[0032] The internal anchoring foundation is fixed on the seabed and is located directly below the buoy. The internal anchoring foundation is provided with a guide chain hole through which the internal mooring cable is passed. being tensionedly connected to the float;

[0033] The outer anchoring foundation is fixed on the seabed and is tensionedly connected to the mooring array via the outer mooring cable, which is in the form of a catenary.

[0034] Preferably, the buoy, the internal anchoring foundation, and the internal mooring cable , Internal mooring lines It is shared by two adjacent floating aquaculture cages.

[0035] Preferably, a plurality of the floating aquaculture cages are arranged in an equilateral triangle or square array, and the buoy is placed at the center of the equilateral triangle or square formed by the floating aquaculture cages.

[0036] Compared with the prior art, the beneficial effects are as follows:

[0037] 1. Adjacent floating aquaculture cages share buoys, mooring cables, and anchor foundations, which can reduce the number of anchor foundations used and reduce the installation and construction costs of the floating aquaculture cage group mooring system;

[0038] 2. Adjacent floating aquaculture cages use the mooring method of "buoy-mooring cable-anchor foundation". Compared with the catenary mooring method, the "buoy-mooring cable-anchor foundation" mooring method has a small mooring radius, large horizontal restoring force, and small vertical load, which can increase the density of cage deployment and improve the utilization rate of sea use. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 A top view of the shared mooring system structure of a group of three-point moored floating aquaculture cages. The circle is the buoy, the hexagon is the floating aquaculture cage, and the connecting line between the buoy and the floating aquaculture cage is the internal mooring cable. , the straight line with an arrow is the outer mooring cable, the square is the outer anchoring foundation, and the outer anchoring foundation is connected to the outer mooring cable.

[0040] Figure 2 Schematic diagram of the mooring structure of a single floating aquaculture cage with three-point mooring. The sphere is the buoy, the hexahedron is the floating aquaculture cage, the cube is the internal anchor foundation, and the connecting line between the buoy and the internal anchor foundation is the internal mooring cable .

[0041] Figure 3 This is a schematic diagram of a single buoy mooring structure with three-point mooring. The sphere is the buoy, the hexahedron is the floating aquaculture cage, and the cube is the internal anchoring foundation.

[0042] Figure 4 Schematic diagram of the mooring structure of a single floating aquaculture cage with three-point mooring and an outer anchor foundation. The sphere is the buoy, the hexahedron is the floating aquaculture cage, the cube is the internal anchor foundation, and the quadrangular prism is the outer anchor foundation.

[0043] Figure 5 This is a schematic diagram of the mooring structure of a single buoy and an outer anchor foundation for three-point mooring. The sphere is the buoy, the hexahedron is the floating aquaculture cage, the cube is the internal anchor foundation, and the quadrangular prism is the outer anchor foundation.

[0044] Figure 6 A top view of the shared mooring system structure of a four-point moored floating aquaculture cage group. The circle is the buoy, the hexagon is the floating aquaculture cage, and the connecting line between the buoy and the floating aquaculture cage is the internal mooring cable. , the straight line with an arrow is the outer mooring cable, the square is the outer anchoring foundation, and the outer anchoring foundation is connected to the outer mooring cable.

[0045] Figure 7 Schematic diagram of the mooring structure of a single floating aquaculture cage with four-point mooring. The sphere is the buoy, the hexahedron is the floating aquaculture cage, the cube is the internal anchor foundation, and the connecting line between the buoy and the internal anchor foundation is the internal mooring cable .

[0046] Figure 8 This is a schematic diagram of a single buoy mooring structure with four-point mooring. The sphere is the buoy, the hexahedron is the floating aquaculture cage, and the cube is the internal anchoring foundation.

[0047] Fig. 9 Schematic diagram of the mooring structure of a single floating aquaculture cage with four-point mooring and an outer anchor foundation. The sphere is the buoy, the hexahedron is the floating aquaculture cage, the cube is the internal anchor foundation, and the quadrangular prism is the outer anchor foundation.

[0048] Fig.10 This is a schematic diagram of the mooring structure of a single buoy and an outer anchor foundation for four-point mooring. The sphere is the buoy, the hexahedron is the floating aquaculture cage, the cube is the internal anchor foundation, and the quadrangular prism is the outer anchor foundation.

[0049] Fig.11 Internal mooring line With internal mooring line Schematic diagram of the floor plan.

[0050] Fig.12 This is a plan view of the outer mooring cable.

[0051] 1- Internal mooring line ; 2-Internal mooring line ; 3-Outer mooring line. DETAILED DESCRIPTION

[0052] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0053] Figure 11-Figure 12 As shown, a shared mooring design method for a floating aquaculture cage group comprises:

[0054] For internal mooring lines , get the internal mooring line The horizontal and vertical distances between the two end points, through the internal mooring line The catenary equation is used to calculate the internal mooring cable the tension at the fairlead and the horizontal component of tension;

[0055] For the internal anchor foundation, based on the force on the float, the net load on the internal anchor foundation is calculated, and based on the net load on the internal anchor foundation, the parameters of the internal anchor foundation are obtained;

[0056] For the outer mooring cable, based on the balance law of a single cage force, calculate the horizontal component of the tension of the outer mooring cable at the chain guide hole, obtain the horizontal distance and vertical distance between the two end points of the outer mooring cable, and calculate the tension of the outer mooring cable at the chain guide hole according to the catenary equation of the outer mooring cable;

[0057] For the outer anchor foundation, the net load on the outer anchor foundation is obtained, and then the parameters of the outer anchor foundation are obtained.

[0058] Internal mooring lines The parameter calculation steps are as follows:

[0059] Step 1: Input the internal mooring line The basic parameters, including the internal mooring lines The initial length , Internal mooring lines Weight in water , Internal mooring lines The elastic modulus , Internal mooring lines Cross-sectional area ;

[0060] Step 2: Obtain the internal mooring line End point coordinates, get the internal mooring line Horizontal distance and vertical distance ; Internal mooring lines The catenary equation is calculated as follows:

[0061] ;

[0062] ;

[0063] Step 3: Calculate the horizontal component of the mooring cable at the fairlead hole using the catenary equation. .

[0064] The calculation steps of internal anchor foundation parameters are as follows:

[0065] Step 1: Input the buoyancy of the float ,gravity , the internal mooring line The initial length , Internal mooring lines Weight in water ;

[0066] Step 2: The floating ball is in a balanced state, and the vertical force it is subjected to includes buoyancy. ,gravity and an internal mooring line Tension According to the force balance relationship, the internal mooring cable is calculated The tension at the connection with the float , the calculation formula is as follows:

[0067] ;

[0068] Step 3: Due to the internal mooring line The two ends are connected to the floating ball and the internal anchor foundation respectively, so the net load on the internal anchor foundation is Equal to the internal mooring line Tension Minus the internal mooring lines Weight in water, based on the net load on the internal anchor foundation , get the parameters of the internal anchor foundation, The calculation formula is as follows:

[0069] .

[0070] The relevant parameters of the outer mooring line are calculated as follows:

[0071] Step 1: Input the basic parameters of the outer mooring cable, including the weight of the outer mooring cable in water. , elastic modulus of the outer mooring line , cross-sectional area of ​​the outer mooring line ;

[0072] Step 2: The buoy or floating aquaculture cage connected to the outer mooring cable is in a balanced state, and the horizontal force it receives includes the internal mooring cable connected to the buoy or floating aquaculture cage. The horizontal component of the tension at the chain eye and an outer mooring line The horizontal component of the tension at the chain guide hole is calculated according to the law of force balance: , the calculation formula is as follows:

[0073] ;

[0074] The third step is to obtain the coordinates of the outer mooring cable endpoints. , , get the horizontal distance from the outer mooring cable fairlead to the outer anchor foundation and vertical distance , the tension of the outer mooring cable at the chain guide hole The calculation formula is as follows:

[0075] ;

[0076] Length of outer mooring line in water The calculation formula is as follows:

[0077] .

[0078] The deployment steps are as follows:

[0079] A1. Arrange a number of the floating aquaculture cages in an equilateral triangle or square array;

[0080] A2. Place a number of the floating balls at the center of the regular triangle or square formed by the floating aquaculture cages;

[0081] A3. Place a number of internal anchoring foundations directly below the buoy, and the internal anchoring foundations are connected to the buoy through the internal mooring cables. being tensionedly connected to the floating ball directly above;

[0082] A4, the buoy and the floating aquaculture cage located at the vertex of the regular triangle or square are connected by the internal mooring cable Tension connection;

[0083] A5. The outer anchoring foundation is fixed on the seabed and is tensionedly connected to the mooring array through the outer mooring cable, and the outer mooring cable is in the form of a catenary; the outer anchoring foundation and the buoy of the adjacent floating aquaculture cage are in the form of a regular triangle or a square.

[0084] A shared mooring system for a group of floating aquaculture cages, comprising a mooring array, a plurality of outer anchoring foundations, and a plurality of outer mooring cables; wherein:

[0085] The mooring array includes a floating aquaculture cage, a buoy, an internal anchoring foundation, an internal mooring cable, , Internal mooring lines The floating aquaculture cage is located on the sea surface and is provided with a number of chain guide holes, which are evenly distributed around the horizontal circumference of the floating aquaculture cage;

[0086] The buoy is arranged in the seawater, and is provided with the same number of chain guide holes as the chain guide holes of the floating aquaculture cage, and the chain guide holes are evenly distributed around the horizontal circumference of the buoy; the buoy is connected to the floating cage by the internal mooring cable. being tensionedly connected to the floating aquaculture cage;

[0087] The internal anchoring foundation is fixed on the seabed and is located directly below the buoy. The internal anchoring foundation is provided with a guide chain hole through which the internal mooring cable is passed. being tensionedly connected to the float;

[0088] The outer anchoring foundation is fixed on the seabed and is tensionedly connected to the mooring array via the outer mooring cable, which is in the form of a catenary.

[0089] Embodiment 1:

[0090] like Figure 1-Figure 5 As shown, this embodiment provides a shared mooring system suitable for a floating aquaculture cage group, which is composed of a mooring array, a plurality of outer anchoring foundations, and a plurality of outer mooring cables; wherein:

[0091] The mooring array consists of floating aquaculture cages, buoys, internal anchoring foundations, internal mooring cables, , Internal mooring lines The floating aquaculture cage and the buoy are located on the sea surface. A single floating aquaculture cage is provided with three guide chain holes evenly distributed along the horizontal circumference. A single buoy is provided with three guide chain holes evenly distributed along the horizontal circumference. The three buoys are arranged in the sea water with the single floating aquaculture cage as the center, and the angle between the center lines of adjacent buoys is 120°.

[0092] A single buoy is connected to three adjacent floating aquaculture cages by internal mooring cables. Tension connection, three adjacent floating aquaculture cages are evenly distributed on the horizontal circumference with a single buoy as the center;

[0093] The internal anchor foundation is fixed on the seabed, located directly below the buoy. The internal anchor foundation is provided with a guide chain hole through which the internal mooring cable Tension connection with the float;

[0094] The outer anchor foundation is fixed on the seabed and is tensionedly connected to the mooring array through an outer mooring cable, and the outer mooring cable is in the form of a catenary;

[0095] The angle between the outer anchor foundation and the center line of the float of the adjacent floating aquaculture cage is 120°.

[0096] Embodiment 2:

[0097] like Figure 6-Figure 10 As shown, this embodiment provides a shared mooring system suitable for a floating aquaculture cage group, which is composed of a mooring array, a plurality of outer anchoring foundations, and a plurality of outer mooring cables; wherein:

[0098] The mooring array consists of floating aquaculture cages, buoys, internal anchoring foundations, internal mooring cables, , Internal mooring lines The floating aquaculture cage and the buoy are located on the sea surface. A single floating aquaculture cage is provided with four guide chain holes evenly distributed along the horizontal circumference. A single buoy is provided with four guide chain holes evenly distributed along the horizontal circumference. The four buoys are arranged in the sea water with the single floating aquaculture cage as the center, and the angle between the center lines of adjacent buoys is 90°.

[0099] A single buoy is connected to four adjacent floating aquaculture cages by internal mooring cables. Tension connection, four adjacent floating aquaculture cages are evenly distributed on the horizontal circumference with a single buoy as the center;

[0100] The internal anchor foundation is fixed on the seabed, located directly below the buoy. The internal anchor foundation is provided with a guide chain hole through which the internal mooring cable Tension connection with the float;

[0101] The outer anchor foundation is fixed on the seabed and is tensionedly connected to the mooring array through an outer mooring cable, which is in the form of a catenary.

[0102] In the case of Example 1, the horizontal forces include the two internal mooring cables The horizontal component of the tension at the chain eye and an outer mooring line The horizontal component of the tension at the chain guide hole; if it is Example 2, the horizontal force received includes the three internal mooring cables The horizontal component of the tension at the chain eye and an outer mooring line The horizontal component of tension at the chain guide eye.

[0103] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and descriptions are only preferred examples of the present invention and are not intended to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A shared mooring design method for a floating aquaculture cage group, characterized in that: It includes a mooring array, a plurality of outer anchoring foundations, and a plurality of outer mooring cables; wherein: The mooring array is composed of a floating aquaculture cage, a buoy, an internal anchoring foundation, an internal mooring cable a, and an internal mooring cable b; the floating aquaculture cage is located on the sea surface and is provided with a number of chain guide holes, which are evenly distributed around the horizontal circumference of the floating aquaculture cage; For the internal mooring cable a, the horizontal distance between the two end points of the internal mooring cable a is obtained, and the tension of the internal mooring cable a at the fairlead and the horizontal component of the tension are calculated by using the catenary equation of the internal mooring cable a; For the internal anchor foundation, the net load received by the internal anchor foundation is calculated, and based on the net load received by the internal anchor foundation, the parameters of the internal anchor foundation are obtained; For the outer mooring cable, calculate the horizontal component of the tension of the outer mooring cable at the chain guide hole, obtain the horizontal distance between the two end points of the outer mooring cable, and calculate the tension of the outer mooring cable at the chain guide hole according to the catenary equation of the outer mooring cable; For the outer anchor foundation, the net load on the outer anchor foundation is obtained, and then the parameters of the outer anchor foundation are obtained; The calculation steps of the internal mooring line a parameter are as follows: Step 1: input the basic parameters of the internal mooring cable a, including the initial length s1 of the internal mooring cable a, the weight ω1 of the internal mooring cable a in water, the elastic modulus E1 of the internal mooring cable a, and the cross-sectional area A1 of the internal mooring cable a; Step 2: Obtain the endpoint coordinates of the internal mooring cable a to obtain the horizontal distance X of the internal mooring cable a; the catenary equation of the internal mooring cable a is calculated as follows: Step 3: Calculate the horizontal component F of the tension of the internal mooring cable a at the fairlead hole by using the catenary equation; The calculation steps of internal anchor foundation parameters are as follows: Step 1: Input the buoyancy F of the float f , Gravity G f , the initial length s2 of the internal mooring line b, the weight ω2 of the internal mooring line b in water; Step 2: The floating ball is in a balanced state, and the vertical force it is subjected to includes the buoyancy F f , Gravity G f and the tension T of an internal mooring line b a According to the force balance relationship, the tension T at the connection between the internal mooring cable b and the buoy is calculated. a ; T a =F f -G f ; Step 3: Since both ends of the internal mooring cable b are connected to the buoy and the internal anchor foundation respectively, the net load T b is equal to the tension T of the internal mooring line b a Subtract the weight of the internal mooring cable b in water, based on the net load T received by the internal anchor foundation b , get the parameters of the internal anchor foundation, T b The calculation formula is as follows: T b =T a -ω2s2; The relevant parameters of the outer mooring line are calculated as follows: The first step is to input the basic parameters of the outer mooring cable, including the weight ω3 of the outer mooring cable in water, the elastic modulus E3 of the outer mooring cable, and the cross-sectional area A3 of the outer mooring cable; Step 2: The buoy or floating aquaculture cage connected to the outer mooring cable is in a balanced state, and the horizontal force it receives includes the horizontal component of the tension of the inner mooring cable a connected to the buoy or floating aquaculture cage at the chain guide hole and the horizontal component of the tension of an outer mooring cable b at the chain guide hole. According to the law of force balance, calculate the horizontal component F of the tension of the outer mooring cable at the chain guide hole. t , the calculation formula is as follows: F t =F; Step 3: Obtain the coordinates of the outer mooring cable endpoints as (0, 0) and (l2, h2), respectively, and obtain the horizontal distance l2 and vertical distance h2 from the outer mooring cable fairlead to the outer anchor foundation, and the tension T of the outer mooring cable at the fairlead. t The calculation formula is as follows: Length of outer mooring line in water s * The calculation formula is as follows:

2. A shared mooring system for a group of floating aquaculture cages, using the shared mooring design method for a group of floating aquaculture cages as claimed in claim 1, characterized in that: The buoy is arranged in the seawater, and is provided with the same number of chain guide holes as the chain guide holes of the floating aquaculture cage, and the chain guide holes are evenly distributed around the horizontal circumference of the buoy; the buoy is tensionedly connected to the floating aquaculture cage through the internal mooring cable a; The internal anchoring foundation is fixed on the seabed and is located directly below the buoy. The internal anchoring foundation is provided with a chain guide hole and is tensionedly connected to the buoy through the internal mooring cable b. The outer anchoring foundation is fixed on the seabed and is tensionedly connected to the mooring array via the outer mooring cable, which is in the form of a catenary.

3. The shared mooring system for floating aquaculture cages according to claim 2, characterized in that: The buoy, the internal anchoring foundation, the internal mooring cable a and the internal mooring cable b are shared by two adjacent floating aquaculture cages.

4. The shared mooring system for floating aquaculture cages according to claim 2, characterized in that: A plurality of the floating aquaculture cages are arranged in an equilateral triangle or square array, and the buoy is arranged at the center of the equilateral triangle or square formed by the floating aquaculture cages.

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