A comprehensive performance evaluation method for the design of an irregularly stored anchor chain space

Abstract

The present invention relates to the technical field of ship devices, and particularly relates to a comprehensive performance evaluation method for the design of an irregular anchor chain storage space. The present invention establishes a dynamic / kinematic mathematical and mechanical model for the movement of a long chain into the cabin, embeds the model into the Adams solver of simulation software, and on this basis forms a digital twin model for the movement of the long chain into the cabin, thereby generating the results of the long chain into the cabin stacking test corresponding to the design scheme of the irregular chain storage space; then, for the result sets of different schemes, by statistically analyzing the anchor chain stacking forms under different numbers of anchor chains, a relational expression between the number of anchor chains and the relevant parameters of the anchor chain cabin in the irregular chain storage space is proposed in a quantitative regression manner, which can be used as a judgment basis for evaluating whether the irregular chain storage space meets the normal storage of the anchor chain, can accurately and efficiently evaluate the effective cabin volume of the irregular chain storage space, improve the initialization design accuracy of the irregular chain storage space of the anchor system, and provide a reference basis for verifying the design of the irregular chain storage space.

Description

Technical Field

[0001] The present invention relates to the technical field of ship devices, and particularly relates to a comprehensive performance evaluation method for the design of an irregular anchor chain storage space. Background Art

[0002] The anchor system is an important system to ensure the safe anchoring of a ship. Generally, it consists of an anchor handling machine for driving the movement of the anchor chain, an anchor chain locker for storing the anchor chain, and anchor system accessories such as chain rollers, chain stoppers, hawse pipes, and anchor lips for guiding or stopping the movement of the anchor and the anchor chain. As the cabin space for storing the anchor chain, the shape and size of the anchor chain locker should be designed to ensure that its effective volume is sufficient to store all the anchor chains designed to be put into the cabin. In order to pursue superior overall performance, the bow line design of modern large surface ships shows an increasingly slender trend, which results in insufficient cabin space in the bow anchor chain locker to be designed into regular figures, such as: cylindrical, rectangular or square.

[0003] In order to obtain sufficient effective cabin volume to store the anchor chain, the prior art generally uses the ship's outer plate, bulkhead and bottom structure to form an irregular shape similar to an inverted trapezoidal cross-section (as Figure 1 shown). Since there is a lack of evaluation standards and methods for the effective stacking volume of this irregular chain storage space at home and abroad, the shape and size of the formed irregular chain storage space are often not the optimal solutions. This has led to two results: one is that the design scheme of the irregular chain storage space does not meet the chain storage requirements, resulting in rework and modification during the actual ship construction stage; the other is that the design scheme of the irregular chain storage space has a large margin, causing waste of overall cabin space resources. Therefore, how to quantitatively evaluate whether the effective design cabin volume of the irregular chain storage space can meet the normal requirements for the anchor chain to enter the cabin has become an important research topic. Summary of the Invention

[0004] The technical problem to be solved by the present invention is: to propose a comprehensive performance evaluation method for the design of an irregular anchor chain storage space, which can accurately and efficiently evaluate the effective cabin volume of the irregular chain storage space, improve the initialization design accuracy of the irregular chain storage space of the anchor system, and quickly judge the effectiveness of the design of the irregular chain storage space of the anchor system.

[0005] To solve the above technical problem, the technical solution adopted by the present invention is:

[0006] A comprehensive performance evaluation method for the design of an irregular anchor chain storage space, comprising the following steps:

[0007] S1, determine the preliminary design scheme of the irregular chain storage space according to the chain storage space design scheme of the parent ship or the same type of ship;

[0008] S2, establish a dynamics / kinematics model for the movement of the long chain into the cabin;

[0009] S3. Based on the entities, constraints, and mechanical relationships determined by the preliminary design scheme, establish a multi-rigid-body system mechanical model for the long-chain entering the cabin motion;

[0010] S4. Based on the dynamic / kinematic model and the multi-rigid-body system mechanical model, determine the anchor chain constraints corresponding to the long-chain entering the cabin motion to generate a digital twin model of the long-chain entering the cabin motion;

[0011] S5. Conduct corresponding dynamic / kinematic simulations through the digital twin model, output the simulation stacking test results of the long-chain entering the cabin, and evaluate the current design scheme of the chain storage space according to the simulation stacking test results;

[0012] S6. Adopt multiple different design schemes for the chain storage space, repeat steps S2 - S5, and obtain multiple groups of simulation stacking test results of the long-chain entering the cabin;

[0013] S7. Conduct statistical analysis on multiple groups of simulation stacking test results of the long-chain entering the cabin to obtain the correlation law between the dynamic volume of the anchor chain stacking and the volume of the irregular chain storage space during the long-chain entering the cabin motion.

[0014] Furthermore, in step S1, the preliminary design scheme includes the shape, size, material parameters, and specific installation position of the irregular chain storage space.

[0015] Furthermore, in step S2, establishing the dynamic / kinematic model of the long-chain entering the cabin motion includes:

[0016] S21. Code the long-chain system composed of N connectors in ascending order of serial numbers, and establish the basic coordinate system nX n Y n Z n of the whole long-chain system and the local coordinate system kX k Y k Z k ;

[0017] S22. Obtain the structural mass matrix and structural stiffness matrix of the k-th connector through finite element analysis;

[0018] S23. Convert the structural mass matrix and structural stiffness matrix into the generalized mass M p (k) and the generalized stiffness matrix K p (k);

[0019] S24. Establish the structural dynamics equation of the k-th connector:

[0020]

[0021] where: q kFor the k-th connector in the local coordinate system kX k Y k Z k in the generalized coordinates, C P (k) is the damping coefficient matrix, Φ(k,k - 1) is the flexible multi-body system internal transformation matrix operator, f(k - 1) is the generalized constraint force exerted by the (k - 1)-th connector, f(k) is the generalized constraint force exerted by the (k + 1)-th connector, and G is the gravity matrix;

[0022] S25, let k = 1, 2, …, N, and recursively obtain the structural dynamics equation of the entire long-chain system.

[0023] Furthermore, in step S3, the multi-rigid body system mechanical model of the long-chain entering the cabin movement includes:

[0024]

[0025] where: δ = q0 - q; λ = step(q, q0 - d, 1, q0, 0)

[0026] In the formula: F_impact is the damping force between two rigid bodies in the long-chain system; q0 is the initial distance between two rigid bodies about to contact; q is the actual distance between two rigid bodies; d q / d t is the relative velocity between two rigid bodies; k is the stiffness coefficient; e is the collision force exponent; c max is the maximum damping coefficient between two rigid bodies; d is the penetration depth between two rigid bodies.

[0027] Furthermore, in step S4, the generation of the digital twin model of the long-chain entering the cabin movement includes:

[0028] S41, establish a three-dimensional solid model of the entire long-chain system;

[0029] S42, according to the preliminary design scheme of the irregular chain storage space, establish a three-dimensional assembly model of the long-chain system installed in the irregular chain storage space;

[0030] S43, based on the dynamics / kinematics model and the multi-rigid body system mechanical model, use the Matlab recursive function to determine the relevant constraints between the anchor chain components during the long-chain entering the cabin movement;

[0031] S44, based on the three-dimensional assembly model and the relevant constraints between the anchor chain components during the long-chain entering the cabin movement, construct a digital twin model of the long-chain entering the cabin movement.

[0032] Furthermore, the relevant constraints between the anchor chain components include: the rotational constraint of adjacent anchor chains and the collision constraint between any two anchor chains.

[0033] Further, in step S5, the corresponding dynamics / kinematics simulation is carried out, specifically including:

[0034] S51, embedding the digital twin model of the long-chain entering the cabin movement into the simulation software solver;

[0035] S52, setting the solution scheme for the long-chain entering the cabin movement in the simulation software solver;

[0036] S53, outputting the simulation stacking test results of the long-chain entering the cabin.

[0037] Further, the setting of the solution scheme for the long-chain entering the cabin movement specifically includes: setting of the driving parameters of the anchor chain movement, setting of the rolling friction parameters of the chain guide roller, setting of the swivel link parameters, setting of the shackle and anchor rod link parameters, setting of the anchor rod and anchor claw link parameters, setting of the swivel and anchor rod link parameters, setting of the contact parameters of the manual components of the anchor system, and setting of the contact parameters of the automatic components of the anchor system.

[0038] Further, the simulation stacking test results of the long-chain entering the cabin include a simulation data set of the number n of anchor chains, the stacking height h of the anchor chains, the volume V of the stacked anchor chains, and the approximate circular diameter D after the anchor chains are stacked during the stacking process of the anchor chains.

[0039] Further, the statistical analysis of the simulation stacking test results of multiple groups of long-chains entering the cabin is specifically to perform a regression analysis on the simulation data set, obtain the mutual relationship between the parameters and establish a correlation equation between the parameters, and then summarize the correlation law between the dynamic volume of the anchor chain stacking and the volume of the irregular chain storage space during the long-chain entering the cabin movement.

[0040] The present invention has the following main advantages compared with the prior art:

[0041] By establishing the dynamic / kinematic mathematical and mechanical models of the long-chain entering the cabin movement, embedding the model into the simulation software Adams solver, and forming a digital twin model of the long-chain entering the cabin movement on this basis, the present invention generates the simulation stacking test results of the long-chain entering the cabin corresponding to the design scheme of the irregular chain storage space; then, for the result sets of different schemes, by statistically analyzing the stacking forms of the anchor chains under different numbers of anchor chains and using the quantitative regression method, the relationship formula between the number of anchor chains and the relevant parameters of the anchor chain cabin under the irregular chain storage space is proposed, which can be used as the judgment basis for evaluating whether the irregular chain storage space meets the normal storage of the anchor chain, can accurately and efficiently evaluate the effective cabin volume of the irregular chain storage space, improve the initialization design accuracy of the irregular chain storage space of the anchor system, can quickly judge the effectiveness of the design of the irregular chain storage space of the anchor system, and provide a reference basis for verifying the design of the irregular chain storage space. Description of the Drawings

[0042] Figure 1Schematic diagram of the irregular storage space (similar to an inverted trapezoid) for the anchor chain of the present invention;

[0043] Figure 2 Flowchart of the design evaluation method for the irregular chain storage space of the anchor system of the present invention;

[0044] Figure 3 Schematic diagram for judging the contact state of the anchor chain of the present invention;

[0045] Figure 4 Flowchart of the solution algorithm for the dynamic / kinematic mathematical model of the long chain entering the cabin of the present invention;

[0046] Figure 5 Schematic diagram of the steps for generating the digital twin model of the long chain entering the cabin of the present invention;

[0047] Figure 6 Schematic diagram of the regression curve between the number of anchor chains n and the stacking height h of the present invention;

[0048] Figure 7 Schematic diagram of the regression curve between the number of anchor chains n and the stacking volume V of the present invention;

[0049] Figure 8 Schematic diagram of the regression curve between the number of anchor chains n and the approximate diameter D of the bottom circle of the stack of the present invention;

[0050] Figure 9 Partial assembly schematic diagram of the long chain entering the cabin of the present invention;

[0051] Figures 10 to 17 Schematic diagrams of the states of the first section, 300, 600, 900, 1200, 1500, 1800, and 2100 anchor chains entering the cabin of the present invention respectively. Detailed implementation manners

[0052] 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 with reference to 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. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0053] It should be noted that according to the needs of implementation, the various steps / components described in this application can be split into more steps / components, or two or more steps / components or partial operations of steps / components can be combined into new steps / components to achieve the objectives of the present invention.

[0054] Embodiment 1. This embodiment provides a comprehensive performance evaluation method for the design of an irregular storage space for anchor chains, as Figure 2As shown in the figure, first, the preliminary design of the irregular chain storage space of the anchor system is carried out through the parent ship or the same type of ship scheme. A dynamic / kinematic model of the long-chain entering the cabin movement is established. According to the entities, constraints, and mechanical relationships determined by the preliminary scheme, a multi-rigid-body system mechanical model is formed. The digital twin model of the long-chain entering the cabin movement is quickly generated using the intelligent setting algorithm, and the corresponding dynamic / kinematic simulation is carried out. The irregular chain storage space scheme that meets the requirements is output through optimization iteration, and an effective empirical formula for the irregular chain storage space is summarized during this process to guide the initial scheme design of subsequent ships.

[0055] (1) Establish the dynamic / kinematic mathematical and mechanical models of the long-chain entering the cabin movement

[0056] The movement process of the anchor chain is abstracted into a multi-rigid-body dynamics model composed of large-range relative motion objects, and a stylized dynamic mathematical model applicable to any topology is established using basic mechanical principles. The long-chain multi-rigid-body system is divided into: components, constraints, forces, and custom parts. Six first-order dynamic equations (describing the relationship between force and acceleration) and six first-order kinematic equations (describing the relationship between position and velocity) are established for each component. Several algebraic constraint equations (the number of equations is the same as the number of degrees of freedom it restricts) are listed for each constraint, and various force characteristics are provided. On this basis, a dynamic equation for the long-chain movement described by generalized coordinates is derived.

[0057] First, the open-chain system of the long-chain entering the cabin is encoded in the order of increasing serial numbers, and the corresponding basic coordinate system nX n Y n Z n and the local coordinate system kX k Y k Z k are established. And the origin of the coordinate is located on the hinge axis, and the Z-axis coincides with the hinge axis.

[0058] In a multi-body system composed of N connectors, any flexible body encoded as k is taken out and analyzed using standard finite element analysis software. Assume that the k-th flexible body is composed of n s (k) rigid nodes connected to each other. The j-th node on the k-th flexible body is represented by j k , and the coordinate system fixed to the k-th flexible body is represented by kX k Y k Z k . In this coordinate system, the structural mass matrix and the structural stiffness matrix of the k-th flexible body can be obtained through finite element analysis. Then, a second-order differential equation is established from the structural mass matrix and the structural stiffness matrix:

[0059]

[0060] Where: q k is the generalized coordinate in the coordinate system kX k Y k Z k consolidated on the k-th flexible body. Solving the eigenvalues of this differential equation, the modal vector matrix P(k) = col{P j (k)} of the k-th flexible body is obtained. Where P j (k) represents the modal vector of the j-th node, expressed as:

[0061] P j (k) = [P ij (k), L, P mj (k)] (2)

[0062] Since the structure mass matrix and the structure stiffness matrix are coupling matrices in the coordinate system kX k Y k Z k , it is necessary to transform them into the generalized mass and generalized stiffness matrices in the modal vector:

[0063]

[0064] In the formula, B(k) is the transformation matrix that transforms the nodal coordinate velocities of all nodes on the k-th flexible body into velocities in the coordinate system kX k Y k Z k .

[0065] Taking any flexible body k from the flexible multi-body chain of the long chain for force analysis, it is subjected to the action of the generalized constraint force f(k - 1) of the outer k - 1-th flexible body and the action of the generalized constraint force f(k) of the inner k + 1-th flexible body. At the same time, it is also subjected to its own gravity. Therefore, the structural dynamics equation of the flexible body k is:

[0066]

[0067] Where: C P (k) is the damping coefficient matrix, φ(k, k - 1) is the transformation matrix operator in the flexible multi-body system, and G is the gravity matrix corresponding to the generalized coordinates. Taking values for k in the formula, k = 1, 2,..., N, the structural dynamics equation of the multi-body system can be deduced:

[0068]

[0069] where: M is the generalized mass matrix operator of the system; C is the generalized damping matrix operator of the system; T is the generalized force vector. Since the equation is obtained by recursively deriving the structural dynamics equations of all connecting bodies in the local coordinates of the system to the base coordinates, modal analysis of the entire system can be performed in the base coordinates to obtain the corresponding system modal vectors, and the Ritz method is used to calculate the low-order natural frequencies.

[0070] From the analysis of the structural dynamics equation of the flexible body k, it can be seen that if f(k) is regarded as an R m -dimensional state vector, φ(k,k - 1) is regarded as an R m×m -dimensional state transition matrix, and the combination of other terms is regarded as the product of the dynamic noise driving matrix Γ(k) ∈ R m×r and the white noise W(k) ∈ Rr. This dynamic equation becomes the standard form of the Kalman filter. With the help of the Kalman filter and the Bryson-Frazier smoother, the continuous-time state space expression of the flexible multi-body system is transformed into a discrete-time state space expression. The vibration characteristics at the connecting hinges can be determined at each step of the recursion. This fundamentally improves the computational efficiency O(n) and the accuracy of the computational results of the structural dynamics analysis.

[0071] Based on the fact that during the movement of the anchor chain, whether in contact or collision, the principles of conservation of momentum and conservation of angular momentum are satisfied, the Lagrangian theory is used to optimize the integral calculation method of the existing solver. The impact function model is used to calculate the magnitude of the contact force. The impact function model is a non-linear spring-damping model, which involves many parameters and has a large amount of calculation. However, since the velocity is continuous, the collision force can be calculated, and to a certain extent, the contact and collision process can be simulated more realistically. Therefore, the impact function method is mostly used in contact and collision simulation. The contact force calculated by the impact function method consists of two parts, one is the elastic force and the other is the damping force, where the damping force is generated by the relative velocity, and the functional formula is as follows:

[0072]

[0073] where: δ = q0 - q; λ = step(q, q0 - d, 1, q0, 0)

[0074] where: q0 - the initial distance between two rigid bodies about to come into contact; q - the actual distance between the two rigid bodies; d q / d t - the relative velocity between the two rigid bodies; k - the stiffness coefficient; e - the collision force exponent; c max - the maximum damping coefficient; d - the penetration depth, which determines when the damping force reaches its maximum.

[0075] In order to keep the damping force continuous during the rigid body collision process, a piecewise function is adopted in the formula, and its form is step(x, x0, h o , x1, h1).

[0076]

[0077] Where: a = h1 - h0; Δ = (x - x0) / (x1 - x0).

[0078] In order to describe and judge the contact state of the rigid body system during the collision process, it is assumed that there are n p contact points I p where contact is likely to occur. Check how many of these contact points with a higher probability of contact at each moment of motion meet the conditions for a collision, that is, there is indeed contact. Then the n s contact points where a collision occurs form a set I s . For the points in set I s , the closest distance between it and a certain rigid body must be zero, that is, the normal relative distance g N = 0, and it is necessary to perform collision state judgment calculations. For the n s contact points in I that satisfy the normal relative velocity k , they are represented as set I k . The points in I k need to calculate the contact collision force. When it is continuous contact, if it means the termination of the contact state. The termination of the contact can be determined by the normal relative acceleration or the normal contact force λ N . See the contact state judgment diagram in Figure 3 , and see the algorithm description flowchart in Figure 4 .

[0079] (2) Establish a digital twin model for the long-chain into the cabin movement

[0080] Using the established dynamic / kinematic mechanical model of the long-chain into the cabin movement, complete the algorithm embedding based on the commercial simulation design software Adams solver, and on this basis, construct a digital twin model of the long-chain into the cabin movement. The specific steps are shown in Figure 5 .

[0081] First, establish the 3D solid models of the corresponding components according to the working data of each entity component in the long-chain into the cabin movement, ensuring that the sizes of each model are correct and the center of gravity positions are accurate. Then, based on the preliminary scheme of the irregular chain storage space, assemble the solid models of the long-chain into the cabin movement into an assembly model with accurate relative position relationships. Next, construct the digital twin model of the long-chain into the cabin movement by setting the kinematic / dynamic constraints of each solid component model, where the automatic contact setting between the anchor chain components is realized through a Matlab recursive function. Set the solution scheme for the long-chain into the cabin movement through the Adams solver of the commercial simulation software based on the dynamic / kinematic mechanical model already embedded in the long-chain into the cabin movement, specifically including parameters such as stiffness, material damping, penetration depth, Coulomb friction, static and dynamic friction velocities, and coefficients. Finally, output the results of the long-chain into the cabin stacking test through the solution operation to evaluate the rationality and effectiveness of the design of the irregular chain storage space.

[0082] (3) Summarize the relationship law between the dynamic volume of the anchor chain stacking and the volume of the irregular chain storage space in the long-chain into the cabin movement

[0083] By continuously adjusting the scheme of the irregular chain storage space, multiple groups of results of the long-chain into the cabin stacking test can be output. For each group of results, use the segmented annotation technology to divide the entire long chain into several sets, analyze the parameters during the movement and stacking process of each set, and track the stacking shape of each group of anchor chains in real time. After each group of anchor chains is stacked, measure and calculate its stacking height, the approximate circular area after spreading, and the stacking volume. As the time of the anchor chain stacking movement changes, the number of stacked anchor chains will gradually increase. Therefore, a simulation data set of the number of anchor chains n, the stacking height h of the anchor chains, the volume V of the stacked anchor chains, and the approximate circular diameter D after the anchor chains are stacked can be obtained. Through the regression analysis of the data set, the mutual relationships between the parameters can be obtained and a correlation equation can be established. The established equation reflects the correlation law between the dynamic volume of the anchor chain stacking and the volume of the irregular chain storage space in the long-chain into the cabin movement.

[0084] Taking the data set formed in Example 3 for analysis, the relationship between the stacking height h and the number of anchor chains n satisfies the relational formula (see the relationship diagram between the number of anchor chains and the stacking height in Figure 6 ):

[0085] h = 10 0.795 ×n 0.957 , let k 11 = 10 0.795 , then h = k 11 ·n 0.957 (9)

[0086] The relationship between the stacking volume V and the number of anchor chains n satisfies the relational formula (see the relationship diagram between the number of anchor chains and the stacking volume in Figure 7 ):

[0087] V = 102 ×n 3.35 , let k 12 = 10 2 , then V = k 12 ×n 3.35 (10)

[0088] The relationship between the approximate circular bottom diameter D of the stack and the number of anchor chains n is satisfied (see the relationship diagram between the number of anchor chains and the approximate circular diameter at the bottom of the stack in Figure 8 ):

[0089] D = 10 0.843 ·n 1.16 , let k2 = 10 0.843 , then D = k2·n 1.16 (11)

[0090] See the trend diagram of the stacking height of the anchor chain changing with the number of anchor chains in Figure 9 , and see the trend diagram of the stacking volume changing with the height in Figure 9 .

[0091] Example 2. A comprehensive performance evaluation method for the design of an irregular anchor chain storage space provided in this example mainly includes:

[0092] (1) To accurately and effectively evaluate the effective cabin volume of the irregular anchor chain storage space, a dynamic / kinematic model that can truthfully reflect the movement of the long chain into the cabin is constructed. There are a large number of complex discontinuous dynamic processes such as collisions and clearances in the analysis of the anchor chain movement, so a working condition with infinitely many possible contact collisions is formed. This problem of the dynamic / kinematic model with variable topology brings many difficulties to the model establishment, such as: the establishment of dynamic model elements such as collisions and clearances, the judgment of contact points, the realization of system topology switching conditions, etc. At present, the dynamic models built into conventional dynamic simulation software cannot effectively solve discontinuous dynamic processes. The more moving components there are in the calculation, the more likely the equations are to be ill-conditioned and it is difficult to obtain an effective solution. Therefore, accurately constructing the dynamic / kinematic mathematical model of the long chain entering the cabin is the basis for effectively evaluating the effective cabin volume of the irregular anchor chain storage space.

[0093] (2) After establishing the dynamic / kinematic mathematical model of the long-chain entering the cabin movement, a digital twin model of the long-chain entering the cabin movement is established based on this. The biggest difference between this digital twin model and other multi-rigid body models is that the number of moving components involved in this model is relatively large. Usually, the length of the anchor chain of a large surface ship can reach 350m, and the corresponding number of anchor chains exceeds 1500. The corresponding anchor chain constraints include the rotational constraints of adjacent anchor chains and the collision constraints between any two anchor chains. Therefore, the number of motion constraints involved in this model can reach the million level. Obviously, it cannot be completed by manual setting. It is necessary to develop a matching intelligent setting algorithm with the digital twin model to accurately establish the digital twin model of the long-chain entering the cabin movement, so as to avoid problems such as missing settings, incorrect settings, and repeated settings that may occur in the subsequent calculation process.

[0094] (3) Combining the simulation results of the digital twin model of the long-chain entering the cabin movement, summarize, refine, and generalize the empirical formula applicable to the effective volume of the irregular chain storage space of the anchor system, so as to improve the initialization design accuracy of the irregular chain storage space of the anchor system, and at the same time provide a means to quickly judge the effectiveness of the design of the irregular chain storage space of the anchor system.

[0095] Example 3. This example takes a large ship as an example. The bow shape of a large ship is special, and it is relatively difficult to arrange the irregular chain storage space, and there is a risk of insufficient anchor chain storage space. Using the method of this patent, the irregular chain storage space is designed, specifically as follows:

[0096] (1) Three-dimensional modeling and assembly of anchor system parts, establishing a digital twin model, such as Figure 9 .

[0097] (2) To facilitate observing the stacking effect after the anchor chain enters the cabin, first move the starting position of the anchor chain to the position shown in Figure 10 , so that the distance between the leftmost bottom anchor chain and the bottom deck of the anchor chain cabin is close. In this way, when the anchor chain moves, the anchor chain will soon hit the bottom deck of the anchor chain cabin and enter the stacking process. Respectively carry out simulation tests to solve the stacking process of 300, 600, 900, 1200, 1500, 1800, and 2100 anchor chains entering the cabin. As shown in Figures 11 to 17 .

[0098] (3) According to the test solution result set, conduct a detailed analysis of the process of the anchor chain entering the cabin. Now, starting from the first section at the bottom of the entire long chain, every ten sections of the anchor chain are divided into a group, and real-time tracking is carried out, and the relevant data are measured as shown in Table 1 below.

[0099] Table 1 Anchor chain stacking data table

[0100] N (number of anchor chains) 0 100 200 300 400 500 600 h (stacking height) / m 0 0.72 0.72 0.72 0.72 0.72 0.72 <![CDATA[V (bulk volume) / m 3 > 0 0.13 0.13 0.13 0.13 0.13 0.13 N (number of anchor chains) 700 800 900 1000 1100 1200 1300 h (stacking height) / mm 2.17 2.17 2.17 2.17 2.17 2.17 2.17 <![CDATA[V (bulk volume) / m 3 > 0.93 0.93 0.93 0.93 0.93 0.93 0.93 N (number of anchor chains) 1400 1500 1600 1700 1800 1900 200 h (stacking height) / mm 3.00 3.00 3.00 3.00 3.00 3.00 3.00 <![CDATA[V (bulk volume) / m 3 > 1.85 1.85 1.85 1.85 1.85 1.85 1.85

[0101] (4) According to the test solution set, the irregular chain storage space layout plan is modified through simulation iteration, and finally the precise design plan of the irregular chain storage space of this ship is determined. At the same time, in this process, the relationship law between the dynamic volume of the anchor chain accumulation and the volume of the irregular chain storage space is summarized and induced, specifically shown in formulas (9) to (11) in Embodiment 1.

[0102] Furthermore, the parts not detailed in this application are the same as the prior art or are implemented using the prior art.

[0103] In summary:

[0104] The present invention generates the long-chain into-the-cabin accumulation test results corresponding to the irregular chain storage space design plan by establishing the dynamic / kinematic mathematical and mechanical models of the long-chain into-the-cabin movement, embedding the models into the Adams solver of the simulation software, and forming a digital twin model of the long-chain into-the-cabin movement on this basis; then, for the result sets of different plans, by statistically analyzing the anchor chain accumulation forms under different numbers of anchor chains, a relational formula between the number of anchor chains and the relevant parameters of the anchor chain compartment under the irregular chain storage space is proposed in a quantitative regression manner, which can be used as a judgment basis for evaluating whether the irregular chain storage space meets the normal storage of the anchor chain, can accurately and efficiently evaluate the effective cabin volume of the irregular chain storage space, improve the initialization design accuracy of the irregular chain storage space of the anchor system, can quickly judge the effectiveness of the design of the irregular chain storage space of the anchor system, and provide a reference basis for verifying the design of the irregular chain storage space.

[0105] It is easy for those skilled in the art to understand that the above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A comprehensive performance evaluation method for the design of an irregular anchor chain storage space, characterized in that, It includes the following steps: S1. Determine the preliminary design scheme of the irregular chain storage space according to the chain storage space design scheme of the parent ship or the same type of ship; S2. Establish the dynamics / kinematics model of the long chain entering the cabin; The establishment of the dynamics / kinematics model of the long chain entering the cabin includes: S21, encode the long-chain system composed of N connectors in the increasing order of serial numbers, and establish the basic coordinate system nX of the whole long-chain system n Y n Z n and the local coordinate system kX of the k-th connector among them k Y k Z k ; S22. Obtain the structural mass matrix and structural stiffness matrix of the k-th connector through finite element analysis; S23, transform the structural mass matrix and the structural stiffness matrix into a generalized mass M p (k) and a generalized stiffness matrix K p (k); S24. Establish the structural dynamics equation of the k-th connector: where: q k is the generalized coordinate of the k-th connector in the local coordinate system kX k Y k Z k , C P (k) is the damping coefficient matrix, Φ(k,k - 1) is the transformation matrix operator of the flexible multi-body system in the body, f(k - 1) is the generalized constraint force applied by the (k - 1)-th connector, f(k) is the generalized constraint force applied by the (k + 1)-th connector, and G is the gravity matrix; S25. Let k = 1, 2,..., N, and recursively obtain the overall structural dynamics equation of the long chain system; S3. Establish the multi-rigid body system mechanics model of the long chain entering the cabin according to the entities, constraints and mechanical relationships determined by the preliminary design scheme; The multi-rigid body system mechanics model of the long chain entering the cabin includes: where: δ = q0 - q; λ = step(q, q0 - d, 1, q0, 0) Where: F_impact is the damping force between two rigid bodies in the long-chain system; q0 is the initial distance between two rigid bodies about to come into contact; q is the actual distance between the two rigid bodies; d q / d t is the relative velocity between the two rigid bodies; k is the stiffness coefficient; e is the collision force exponent; c max is the maximum damping coefficient between the two rigid bodies; d is the penetration depth of the two rigid bodies; S4. Based on the dynamics / kinematics model and the multi-rigid body system mechanics model, determine the anchor chain constraints corresponding to the long chain entering the cabin to generate the digital twin model of the long chain entering the cabin; S5. Carry out the corresponding dynamics / kinematics simulation through the digital twin model, output the simulation stacking test results of the long chain entering the cabin, and evaluate the current chain storage space design scheme according to the simulation stacking test results; S6. Adopt multiple different chain storage space design schemes, repeat steps S2 - S5, and obtain multiple groups of simulation stacking test results of the long chain entering the cabin; S7. Conduct statistical analysis on multiple groups of simulation stacking test results of the long chain entering the cabin to obtain the correlation law between the dynamic volume of the anchor chain stacking and the volume of the irregular chain storage space during the long chain entering the cabin movement.

2. The comprehensive performance evaluation method for the irregular storage chain locker space design according to claim 1, characterized in that In step S1, the preliminary design scheme includes the shape, size, material parameters and specific installation position of the irregular chain storage space.

3. The comprehensive performance evaluation method for the irregular storage chain locker space design according to claim 1, wherein In step S4, the generation of the digital twin model of the long chain entering the cabin includes: S41. Establish the three-dimensional solid model of the overall long chain system; S42. Establish the three-dimensional assembly model of the long chain system installed in the irregular chain storage space according to the preliminary design scheme of the irregular chain storage space; S43. Based on the dynamics / kinematics model and the multi-rigid body system mechanics model, use the Matlab recursive function to determine the relevant constraints between the anchor chain components during the long chain entering the cabin movement; S44. Based on the three-dimensional assembly model and the relevant constraints between the anchor chain components during the long chain entering the cabin movement, construct the digital twin model of the long chain entering the cabin.

4. The comprehensive performance evaluation method for the irregular storage chain locker space design according to claim 3, wherein The relevant constraints between the anchor chain components include: the rotational constraint of adjacent anchor chains and the collision constraint between any two anchor chains.

5. The comprehensive performance evaluation method for the irregular storage chain locker space design according to claim 3, characterized in that In step S5, the implementation of the corresponding dynamics / kinematics simulation specifically includes: S51. Embed the digital twin model of the long chain entering the cabin into the simulation software solver; S52. Set the solution scheme for the long chain entering the cabin movement in the simulation software solver; S53. Output the simulation stacking test results of the long chain entering the cabin.

6. The comprehensive performance evaluation method for the irregular storage chain locker space design according to claim 5, characterized in that The described solution for solving the long chain entering the cabin movement specifically includes: setting of the driving parameters of the anchor chain movement, setting of the rolling friction parameters of the chain guide roller, setting of the swivel link parameters, setting of the shackle and anchor rod link parameters, setting of the anchor rod and anchor claw link parameters, setting of the swivel and anchor rod link parameters, setting of the contact parameters of the manual components of the anchor system, and setting of the contact parameters of the automatic components of the anchor system.

7. An integrated performance evaluation method for the design of an irregular anchor chain storage space according to claim 5, characterized in that The results of the long chain entering the cabin simulation stacking test include a simulation data set of the number n of anchor chains, the stacking height h of the anchor chains, the volume V of the stacked anchor chains, and the approximate circular diameter D after the anchor chain stacking is completed during the anchor chain stacking process.

8. An integrated performance evaluation method for the spatial design of irregularly stored anchor chains according to claim 7, characterized in that The statistical analysis of the results of multiple groups of long chain entering the cabin simulation stacking tests specifically involves performing a regression analysis on the simulation data set to obtain the mutual relationship between the parameters and establish a correlation equation between the parameters, and then summarizing the correlation law between the dynamic volume of the anchor chain stacking and the volume of the irregular chain storage space during the long chain entering the cabin movement.

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