System and method for simulating impact process of waves on straight wall structure

Abstract

The invention relates to a simulation system and method for the impact process of waves on a straight wall structure, and the system can obtain the wave height data of water flow fluctuation and the pressure data of a plurality of sampling points on a straight wall type building in real time through the arrangement of an acquisition device, and can achieve the simulation of the impact process of waves on the straight wall structure through the arrangement of a simulation device by employing the wave height data and the pressure data obtained by the acquisition device. And pressure intensity information of the straight wall type building at different heights when the straight wall type building is impacted by the regular waves is obtained through a smoothed particle fluid hydrodynamic simulation algorithm. The smoothed particle fluid hydrodynamic simulation algorithm can be used for carrying out numerical model verification on regular wave motion characteristics and carrying out numerical simulation on the impact of waves on the straight wall type building, and also can be used for calculating the rising duration curves of wave surfaces in front of a slope and on the slope and the pressure values of different heights on the straight wall type building when the regular waves impact; and the simulation effect is effective.

Description

Technical Field

[0001] The present invention relates to the technical field of computer modeling and systems, and more particularly, to a system and method for simulating the impact process of waves on a straight wall structure. Background Art

[0002] When designing marine structures, the impact of waves on them needs to be considered. Specifically, it is necessary to obtain the pressure value distribution at different heights when waves impact marine structures to find the position and action time of the maximum pressure, and calculate the wave force acting on the marine structure. As an important form of marine structures, straight-wall buildings are an important type of building in coastal engineering. The magnitude of the wave force directly affects the safety and cost of straight-wall buildings. Since the nearshore wave force (i.e., nearshore wave dynamics) varies greatly due to factors such as terrain, especially with wave breaking, it increases the difficulty of determining the wave force distribution on straight-wall buildings.

[0003] To address the above difficulties, in the prior art, a method of constructing a physical model of fluid impact on a straight wall was proposed to determine the wave force distribution on straight-wall buildings. However, due to differences in model assumptions in the construction of physical models and differences in the ideas of wave force data analysis, the resulting results vary greatly.

[0004] Regarding the limitations of physical models, the prior art also discloses the Smoothed Particle Hydrodynamics (SPH) modeling method, which can be applied to handle large deformations and free surface flows. However, this method is difficult to accurately simulate the complex shape of waves and their dynamic effects on straight-wall buildings, and there are also technical defects such as high computational costs. Summary of the Invention

[0005] The technical problem to be solved by the present invention is how to overcome the technical defects that the SPH modeling method in the prior art is difficult to accurately simulate the complex shape of waves and their dynamic effects on straight-wall buildings and has high computational costs. To overcome the above defects of the prior art, the present invention provides a system and method for simulating the impact process of waves on a straight wall structure, specifically including a system for simulating the impact process of waves on a straight wall structure and a method for simulating the impact process of waves on a straight wall structure.

[0006] A system for simulating the impact process of waves on a straight wall structure provided by the present invention includes: A collection device configured to obtain in real time the wave height data of water flow fluctuations and the pressure data at a plurality of sampling points on a straight-wall building; The simulation device is electrically connected to the acquisition device and is configured to use the wave height data and pressure data obtained by the acquisition device to obtain pressure information at different heights of the straight-wall building when a regular wave impacts the straight-wall building through a smooth fluid particle fluid hydrodynamic simulation algorithm.

[0007] The disclosed system for simulating the impact of waves on vertical-wall structures addresses the technical problems of the present invention. By providing a collection device, wave height data of water flow fluctuations and pressure data at several sampling points on a vertical-wall structure can be acquired in real time. A simulation device is then provided to utilize the wave height and pressure data acquired by the collection device, and pressure information at different heights of the vertical-wall structure when a regular wave impacts the structure is obtained using a smooth fluid particle hydrodynamic simulation algorithm. Because the smooth fluid particle hydrodynamic simulation algorithm can numerically model the motion characteristics of regular waves and perform numerical simulations of wave impacts on vertical-wall structures, and can also calculate the wave surface elevation duration curves before and on the slope during regular wave impacts, as well as pressure values at different heights on the vertical-wall structure, the algorithm can accurately simulate the propagation of regular waves and their impact on the vertical-wall structure. This not only reduces computational complexity but also results in good agreement with experimental data, ensuring the validity of the simulation. The algorithm also further reveals key factors influencing impact pressure and provides effective design optimization recommendations.

[0008] In one possible embodiment, the acquisition device includes at least one wave height meter G1 arranged in front of the slope, at least one wave height meter G2 arranged on the slope, and several pressure sensors arranged on the straight-wall building, and all of the wave height meters G1, all of the wave height meters G2, and all of the pressure sensors are electrically connected to the simulation device; arranging wave height meters in different places can provide wave height data for calculating simulation and wave height data for verification, and arranging pressure sensors at multiple positions can collect pressure data at different positions, forming pressure time curves of these different positions, further improving the accuracy of obtaining pressure information at different heights of the wall-type building.

[0009] In one possible implementation, the simulation device is configured to perform the following steps: A1: Formulate the integral approximation rule of the field function based on the kernel function approximation method; A2: Rewrite the fluid control equation according to the integral approximation rule to obtain the discrete form of the control equation; A3: rewrite the density diffusion equation according to the integral approximation rule to obtain the density diffusion term, and combine the density diffusion term with the discrete form of the control equation to obtain the hydrodynamic equation of the smooth fluid particle fluid; A4: Obtain the time integral format of the smooth fluid particle fluid hydrodynamic equation by a time integral format construction method; A5: Introduce dynamic boundary conditions on the basis of the time integration format to obtain the definite solution form of the numerical differential equation; A6: Construct a numerical water tank based on the characteristic dimensions of the straight-wall building, and use a wave paddle to generate regular waves in the numerical water tank; A7: According to the regular waves generated in step A6, select the particle sizes of different fluid particles to obtain the time history curves of the wave surfaces of the regular waves with different particle sizes, and compare these time history curves with the wave height data obtained by the acquisition device respectively to select the optimal particle size for accuracy and calculation time; A8: Simulate the wave impact of the regular waves with the optimal particle size on the straight-wall building in the numerical water tank, and substitute the wave height data and pressure data obtained by the acquisition device into the definite solution form of the numerical differential equation to obtain the pressure information at different heights of the straight-wall building; This solution analyzes the wave impact process at different water depths by establishing a numerical wave tank based on the characteristic dimensions of the straight-wall building, using a wave paddle to generate regular waves to form the time history curve of the wave surface. The obtained pressure information at different heights of the straight-wall building can also be used to form the time history curve of the pressure change with time, so as to accurately obtain the force action information of the waves on the straight-wall building in real time.

[0010] In a possible implementation manner, the integral approximation rule includes: First, approximate the field function, the derivative of the field function, or the field function and its derivative by integral based on a smooth kernel function; the smooth kernel function is a fifth-order spline kernel function; Second, discretize the water flow into a series of orthogonally distributed fluid particles, and convert the integral approximation representation of the field function, the derivative of the field function, or the field function and its derivative of each fluid particle into a summation form by the numerical summation approximation method of adjacent fluid particles; The choice of the smooth kernel function has a great influence on the calculation results and must satisfy the following three properties: positive definiteness within the compact support domain; being in a standardized form within the compact support domain; monotonically decreasing as the distance between fluid particles increases; and the fifth-order spline kernel function just meets this requirement, thus being able to improve the calculation efficiency and accuracy.

[0011] In a possible implementation manner, the discrete form of the control equation includes: Momentum equation: , , , , ; Monaghan equation: , ; Continuity equation: ; In the formula, represents the viscous term determined by the fluid particle and the adjacent fluid particle ; is the acceleration of gravity; and represent the fluid particle; [[ID=2,9]]represents the density of the fluid particle; represents the fluid particle pressure; represents the position of the fluid particle; represents the flow velocity of the fluid particle; represents the fluid particle and the adjacent fluid particle determined by the smoothing kernel function; represents the smoothing length of the smoothing kernel function; represents the speed of sound; represents the mass of the fluid particle; represents the introduced correction coefficient; represents the smoothing kernel function for the derivative operation; represents the fluid particle and the adjacent fluid particle relative velocity; This scheme uses the artificial viscosity method to simulate the dynamic characteristics of the fluid in the addition of the viscous term. It has the characteristics of simple form and is widely used in simulating and calculating the fluid viscosity. It can not only ensure the improvement of calculation accuracy, but also relieve the calculation pressure.

[0012] In a possible implementation manner, the formula of the density diffusion term is as follows: , , In the formula, represents the proportionality coefficient; Represent fluid particles The distance vector from the fluid particles Projection along the x-axis; Due to the disordered distribution of fluid particles, the density scalar field undergoes high-frequency low-amplitude oscillations. Therefore, adding a density diffusion term to the continuity equation can reduce density fluctuations.

[0013] In a possible implementation, the time integration format is the Simpson numerical integration format; the numerical integration of the Simpson numerical integration format is reversible in time, has an integral form of second-order accuracy, and is a quantization method composed of a prediction stage and a correction stage, which can achieve the effects of high computational efficiency and accuracy.

[0014] In a possible implementation, the regular wave is a second-order Stokes wave; the simulated wave shape can propagate stably, with high accuracy and is easy to implement.

[0015] Another technical solution of the present invention is to provide a method for simulating the impact process of waves on a vertical wall structure, which includes the following steps: S1: Real-time obtain the wave height data of water flow fluctuations and the pressure data at several sampling points on the vertical wall structure through a collection device; S2: Use the wave height data and pressure data obtained by the collection device through a simulation device, and obtain the pressure information at different heights of the vertical wall structure when a regular wave impacts the vertical wall structure by using the smooth particle hydrodynamics (SPH) simulation algorithm.

[0016] The method disclosed by the present invention can first obtain the wave height data of water flow fluctuations and the pressure data at several sampling points on the vertical wall structure in real time through a collection device, and then use the wave height data and pressure data obtained by the collection device through a simulation device, and obtain the pressure information at different heights of the vertical wall structure when a regular wave impacts the vertical wall structure by using the smooth particle hydrodynamics (SPH) simulation algorithm. Since the smooth particle hydrodynamics (SPH) simulation algorithm can verify the numerical model of the motion characteristics of regular waves and perform numerical simulations of the impact of waves on vertical wall structures, and can also calculate the wave surface elevation duration curve in front of and on the slope and the pressure values at different heights on the vertical wall structure when a regular wave impacts, this algorithm can accurately simulate the propagation of regular waves and their impact on vertical wall structures, not only reducing the computational complexity, but also having good agreement with experimental data, making the simulation results effective. It can further reveal the key factors affecting the impact pressure and provide effective design optimization suggestions. Description of the Drawings

[0017] Figure 1 It is a schematic structural diagram of a system for simulating the impact process of waves on a vertical wall structure disclosed in an embodiment of the present application; Figure 2 It is the operation flow chart of the simulation device disclosed in the embodiments of the present application; Figure 3 It is the schematic diagram of the convergence verification numerical flume model disclosed in the embodiments of the present application; Figure 4 It is the comparison chart of the wave surface elevation process at different particle sizes at a distance of x = 2 m from the upstream boundary disclosed in the embodiments of the present application; Figure 5 It is the comparison chart of the wave surface elevation process at different particle sizes at a distance of x = 4 m from the upstream boundary disclosed in the embodiments of the present application; Figure 6 It is the schematic diagram of the numerical flume and the straight wall building model structure disclosed in the embodiments of the present application; Figure 7 It is a kind of impact pressure duration curve under the condition of water depth of 0.3 m disclosed in the embodiments of the present application; Figure 8 It is another kind of impact pressure duration curve under the condition of water depth of 0.3 m disclosed in the embodiments of the present application; Figure 9 It is the one under the condition of water depth of 0.3 m disclosed in the embodiments of the present application a impact pressure duration curve at the point; Figure 10 It is the one under the condition of water depth of 0.3 m disclosed in the embodiments of the present application b impact pressure duration curve at the point; Figure 11 It is the one under the condition of water depth of 0.3 m disclosed in the embodiments of the present application c impact pressure duration curve at the point; Figure 12 It is the one under the condition of water depth of 0.3 m disclosed in the embodiments of the present application d impact pressure duration curve at the point; Figure 13 It is a kind of impact pressure duration curve under the water depth of 0.325 m disclosed in the embodiments of the present application; Figure 14 It is another kind of impact pressure duration curve under the condition of water depth of 0.325 m disclosed in the embodiments of the present application; Figure 15 It is the one under the condition of water depth of 0.325 m disclosed in the embodiments of the present application a impact pressure duration curve at the point; Figure 16 It is the one under the condition of water depth of 0.325 m disclosed in the embodiments of the present application b impact pressure duration curve at the point; Figure 17 The impact pressure duration curve at the point under the condition of water depth of 0.325 m disclosed in the embodiments of the present application; c ; Figure 18 The impact pressure duration curve at the point under the condition of water depth of 0.325 m disclosed in the embodiments of the present application; d ; Figure 19 The comparison diagram of the time variation curve of the pressure on the straight-wall structure and the test results under the condition of water depth of 0.3 m disclosed in the embodiments of the present application; Figure 20 The comparison diagram of the time variation curve of the pressure on the straight-wall structure and the test results under the condition of water depth of 0.325 m disclosed in the embodiments of the present application; Figure 21 The first impact process and the change of the velocity field disclosed in the embodiments of the present application; Figure 22 The second impact process and the change of the velocity field disclosed in the embodiments of the present application. Detailed implementation manners

[0018] First of all, those skilled in the art should understand that these implementation manners are only used to explain the technical principle of the embodiments of the present application, and are not intended to limit the protection scope of the embodiments of the present application. Those skilled in the art can make adjustments according to needs to adapt to specific application scenarios.

[0019] In the description of the embodiments of the present application, it should be noted that unless otherwise clearly specified and limited, the terms "electrically connected" and "electric connection relationship" should be understood in a broad sense, that is, a connection method with an electrical relationship. For example, it can be a circuit connection through a wire, or an electrical connection through a radio signal channel (channel), or a combination of both. In addition, the "electrically connected" and "electric connection relationship" can be established on the basis of a mechanical connection (such as a wire arranged in a connection key); it can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to specific situations. The communication connection means that the two connected parties have a signal transmission relationship, which can be electrically connected through devices such as cables, or can be achieved through a channel.

[0020] The present application will be further described in detail below with reference to the drawings and specific embodiments.

[0021] Refer to Figure 1 and Figure 2 , the embodiments of the present application disclose a simulation system for the impact process of waves on a straight-wall structure, and its structural schematic diagram is as Figure 1As shown, the system includes a collection device and a simulation device, and the simulation device is electrically connected to the collection device.

[0022] In this system, the collection device is configured to obtain in real time the wave height data of water flow fluctuations and the pressure data at a number of sampling points on a vertical wall structure. Refer to Figure 1 , in this embodiment, the collection device includes at least one wave height meter G1 arranged in front of the slope (in the ocean), at least one wave height meter G2 arranged on the slope, and a number of pressure sensors arranged on the vertical wall structure. All the wave height meters G1, all the wave height meters G2, and all the pressure sensors are electrically connected to the simulation device.

[0023] Refer to Figure 1 and Figure 2 , in this system, the simulation device is configured to use the wave height data and pressure data obtained by the collection device to obtain the pressure information at different heights of the vertical wall structure when a regular wave impacts the vertical wall structure through the smoothed particle hydrodynamics (SPH) simulation algorithm.

[0024] Refer to Figure 2 , in this embodiment, the simulation device is configured to perform the following steps: A1: Formulate an integral approximation rule for the field function based on the kernel function approximation method.

[0025] Step A1 is actually the application of the theoretical basis of the smoothed particle hydrodynamics (SPH) simulation algorithm model. In this embodiment, the integral approximation rule includes the following two processes: First, represent the field function, the derivative of the field function, or the field function and its derivative by an integral approximation based on a smoothed kernel function; the smoothed kernel function is a fifth-order spline kernel function. Specifically, for the field function , then represent the field function as: , where is the smoothed kernel function, is the position of the fluid particle, represents the smoothing length of the smoothed kernel function, and the region where the smoothed kernel function takes effect is specifically defined by its smoothing radius ; represents the position of an adjacent fluid particle.

[0026] The choice of the smoothed kernel function has a great influence on the model calculation results, and the smoothed kernel function must satisfy the following three properties: positive definiteness within a compact support domain; a standardized form within a compact support domain; and monotonic decrease as the distance between fluid particles increases.

[0027] In this embodiment, the smooth kernel function is the Wendland kernel function, that is, a fifth-order spline kernel function is adopted: , That is, let , where , , Since the Wendland kernel function has better smoothness and better matching for the interaction between waves and marine structures, the Wendland kernel function is often selected to establish a numerical model to simulate the interaction between structures and waves.

[0028] Secondly, the water flow is discretized into a series of fluid particles distributed orthogonally. By the numerical summation approximation method of adjacent fluid particles, the field function, the derivative of the field function, or the integral approximation of the field function and its derivative of each fluid particle is approximately represented in the form of summation. For the field function , its integral expression is discretized as: , , where and are the mass and density of the fluid particles and the adjacent fluid particles respectively, and represents the position vector of the fluid particle .

[0029] A2: Rewrite the fluid control equation according to the integral approximation rule to obtain the discrete form of the control equation.

[0030] Specifically in this embodiment, the field function represents the function on the right side of the equal sign in the fluid control equation and the density diffusion equation. Under the rule formulated in step A1, the simulation device processes the control equation into the following discrete form: Momentum equation: , , , , ; Monaghan equation: , ; Continuity equation: ; , where represents the fluid particle and the adjacent fluid particle Determined viscous term; is the acceleration due to gravity; represents a fluid particle density; represents the fluid particle pressure; represents the position of the fluid particle; represents the flow velocity of the fluid particle; represents the speed of sound; represents the introduction of a correction coefficient; represents the smooth kernel function for derivative operation; represents a fluid particle and adjacent fluid particles relative velocity.

[0031] Specifically, the general form of the momentum equation is: , wherein, represents the viscous term, is the acceleration due to gravity. In the simulation device, the artificial viscosity method is used to simulate the dynamic characteristics of the fluid. Due to its simple form, it is widely used in simulating and calculating the fluid viscosity. Under the rule rewrite of step A1, the discrete form of the momentum equation of the fluid particle can be expressed as: , , wherein and the physical meanings of are the density and pressure of the fluid particle respectively (in engineering, pressure is also called stress).

[0032] Viscous term The specific form is as follows: , wherein, and and and respectively represent the position and flow velocity of the fluid particle, , is the average speed of sound, and is the introduced correction coefficient to ensure normal viscous diffusion and appropriate dissipation. In this embodiment The value is 0.01, which makes it more effective when studying the interaction between waves and coastal structures.

[0033] It is then assumed that the fluid is weakly compressible, and the fluid pressure can be determined using the equation of state based on the density of the fluid particles to adjust the compressibility. Monaghan proposed the relationship between the pressure and density between fluid particles as follows: , In the formula , , is the initial density, is the speed of sound.

[0034] Finally, the smooth fluid particle hydrodynamic simulation algorithm requires that the mass of each fluid particle remain constant. Under the rules of step A1, the density change value is obtained through the continuity equation, and the discrete form of the continuity equation is obtained as follows: .

[0035] A3: Rewrite the density diffusion equation according to the integral approximation rule to obtain the density diffusion term, and combine the density diffusion term with the discrete form of the governing equation to obtain the hydrodynamic equation for the smooth fluid particle fluid.

[0036] In this step, the density diffusion term is calculated as follows: , , Where, represents the proportionality coefficient; Representing fluid particles With fluid particles The projection of the distance vector along the x-axis; Due to the disordered distribution of fluid particles, the density scalar field will experience high-frequency and low-amplitude oscillations. Adding a density diffusion term to the continuity equation can reduce density fluctuations.

[0037] A4: The time integral format of the hydrodynamic equations of smooth fluid and particle fluid is obtained by the time integral format construction method.

[0038] It is possible to write the hydrodynamic equation of smooth fluid particle fluid as follows: ; ; ; In this embodiment, the time integration format in this step is the Symplectic numerical integration format. Since the Symplectic numerical integration method is reversible in time and has an integral form with second-order accuracy under the condition of neglecting the viscous term, and it is a quantization method composed of a prediction stage and a correction stage, the Symplectic numerical integration format is adopted in this embodiment. The formulas for the density value and acceleration in the prediction stage are as follows: ; ; In the correction stage, is the correction term, and the equations required for the correction calculation of the velocity value and distribution coordinates of the fluid particles are as follows: ; ; For the explicit time integration scheme, the calculation time step is controlled by the Courant-Friedrichs-Lewy condition (abbreviated as the CFL condition), the pressure term condition, and the viscous diffusion term condition, and the variable time step is calculated according to the formula proposed by Solitary, specifically as follows: , , , is determined by the Courant number and the viscous control time step, and then is determined based on the pressure per unit mass; represents the Courant number.

[0039] A5: Introduce the dynamic boundary condition on the basis of the time integration format to obtain the definite solution form of the numerical differential equation.

[0040] The boundary condition adopted in this embodiment is the dynamic boundary condition (DBC). This boundary condition assumes that the discrete fluid particle motion equation is consistent with the motion equation of the boundary fluid particles in contact at the water tank boundary. The difference is that the fluid particles on the water tank boundary will not move freely under the action of force, but perform specific motions or remain stationary according to the set motion function (such as the motion of the wave-pushing plate and the floating body structure, etc.). In fact, when the non-boundary fluid particles approach the boundary fluid particles and the distance between them is less than , what is affected and changed is the density of the boundary fluid particles, resulting in a rapid increase in the pressure of the solid boundary fluid particles. At the same time, due to the existence of the pressure term in the fluid particle momentum control equation, the fluid particles will be repelled by the solid boundary fluid particles to prevent the fluid particles from entering or passing through the boundary. When the accuracy of the fluid particles is lower, the degree of repulsion of the boundary fluid particles on the non-fluid particles is greater. Improving the accuracy can reduce the disturbance of the repulsive force on the calculation results.

[0041] A6: Construct a numerical water tank based on the characteristic dimensions of the straight-wall building, and use a wave paddle to generate regular waves in the numerical water tank.

[0042] In this embodiment, the regular wave is a second-order Stokes wave because the wave shape simulated by Madsen's second-order wave generation theory can propagate stably, with high accuracy and simple implementation. For the second-order Stokes wave, the motion amplitude of its wave paddle and wave height The calculation formulas are: , , In the above formula is the conversion factor, is the still water depth, is the wave number.

[0043] According to Madsen's theory, the displacement expression of the second-order Stokes regular wave wave paddle is as follows: , In the formula, the first term is the position function of the first-order linear wave, and the second term is the additional term of the second-order position function. In this embodiment, the following limiting conditions are added: , This condition satisfies the second-order wave generation theory, is the wave angular frequency, is the wavelength, is the initial phase; represents the water depth.

[0044] A7: Conduct simulation and convergence analysis. That is, select the particle sizes of different fluid particles to obtain the time history curves of the regular wave surfaces with different particle sizes, and compare these time history curves with the wave height data obtained by the acquisition device respectively to select the optimal particle size for accuracy and calculation time.

[0045] Generate regular waves in the numerical wave tank according to the wave generation method in step A6. Select different particle sizes and measure the time history curves of the wave surface at different positions using wave gauge G1 or wave gauge G2. At the same time, a wave dissipation device can be added to avoid the influence of wave reflection on the results. Compare the obtained time history curves of the wave surface with the theoretical values, and compare the accuracy and calculation time of generating regular waves under different fluid particle radii. Balance efficiency and accuracy to select a suitable particle size.

[0046] See Figure 3 , in this embodiment, a numerical wave tank is established to simulate the propagation of regular waves and perform convergence analysis. The amplitude of the incident wave H= is 0.12 m and the wave period is T = 1.2 s. The fluid particle radii dp are 0.004 m, 0.005 m, and 0.006 m respectively. As Figure 3 shown, the wave pushing plate is 0.2 m away from the upstream boundary, and the numerical wave tank is subjected to wave dissipation treatment. In this numerical wave tank, the wave dissipation function is realized by arranging a damping zone (the wave dissipation zone in the figure) at the rear end of the numerical wave tank, avoiding calculation errors caused by reflected waves.

[0047] Subsequently, calculate the wave surface elevation process at different particle sizes at x = 2 m and x = 4 m away from the upstream boundary. The comparison with the theoretical values (the corresponding values of the second-order Stokes regular wave, and the second-order Stokes regular wave is simply referred to as the second-order Stokes wave in the figure) can be seen in Figure 4 and Figure 5 , Figure 4 is the comparison diagram of the wave surface elevation process at different particle sizes at x = 2 m away from the upstream boundary, Figure 5 is the comparison diagram of the wave surface elevation process at different particle sizes at x = 4 m away from the upstream boundary. It can be seen that the simulated wave surface time history under the three particle sizes is in good agreement with the theoretical values of the second-order Stokes regular wave, and the wave shape is stable with small errors. At the same time, it also shows that the method of the second-order Stokes regular wave is reliable and can be used to simulate the impact process of waves on structures. To balance accuracy and efficiency, the optimal particle size dp = 0.005 m is obtained.

[0048] A8: Simulate the wave impact of the regular wave with the optimal particle size on the vertical wall structure in the numerical wave tank, and substitute the wave height data and pressure data obtained by the acquisition device into the definite solution form of the numerical differential equation to obtain the pressure information at different heights of the vertical wall structure.

[0049] The following will further disclose a method for using the system for simulating the impact of waves on a straight-wall structure in this embodiment, including the following steps: S1: acquiring wave height data of water flow fluctuations and pressure data at several sampling points on the straight-wall building in real time through a collection device; S2: utilizing the wave height data and pressure data obtained by the collection device through a simulation device, and using a smooth fluid particle fluid hydrodynamic simulation algorithm to obtain pressure information at different heights of the straight-wall building when a regular wave impacts the straight-wall building.

[0050] The technical effects of the system for simulating the impact of waves on a straight wall structure in this embodiment will be further described in detail below.

[0051] See also Figure 6 , this embodiment establishes Figure 6 The model structure and parameters of the vertical-wall structure are shown. The slope's bottom edge is 3.62 m from the wave-making plate. The numerical flume uses two operating conditions: static water depths of d = 0.3 m and d = 0.325 m. The wave-making plate generates incident regular waves with a wave height of H = 0.1 m and a wave period of T = 1.3 s. Two wave height meters, G1 and G2, are located at x = 2.643 m and x = 3.943 m, respectively, from the initial position of the wave-making plate. Wave height meter G1 is located before the slope to verify the stability of the generated waves, while wave height meter G2 is located at a slope with a 1:3 split ratio to verify wave behavior near the vertical-wall structure. Figure 6 There is a row of vertically distributed and equally spaced pressure measuring points on the right end of the straight wall structure. These points are sampling points, where pressure sensors are placed. a The point pressure sensor is 0.055 m above the upper platform, from bottom to top. b, c 、 d The distance between the pressures at each measuring point is 0.055 m.

[0052] See also Figures 7 - 12 In this embodiment, the wave surface rise time history of the simulation device numerical simulation (the simulation device numerical simulation is referred to as SPH in the figure, the same below) at the wave height meter G1 and wave height meter G2 under the condition of a water depth of 0.3 m and the impact pressure duration curve of the numerical results of the simulation device simulation compared with the experimental data are calculated. The results are shown in the figure. Figures 7 - 12 As shown. Among them, Figure 7 The shock pressure duration curve is a comparison between the wave surface rise time history of the simulation device at the wave height meter G1 under the condition of 0.3 m water depth and the experimental data measured by the wave height meter G1. Figure 8 The shock pressure duration curve is a comparison between the wave surface rise time history of the numerical simulation of the simulation device at the wave height meter G2 under the condition of a water depth of 0.3 m and the experimental data measured by the wave height meter G2. Figure 9Under the condition of water depth of 0.3 m a The impact pressure duration curve comparing the numerical results simulated by the simulation device at the point with the measurement test data of the pressure sensor passing through this point Figure 10 Under the condition of water depth of 0.3 m b The impact pressure duration curve comparing the numerical results simulated by the simulation device at the point with the measurement test data of the pressure sensor passing through this point Figure 11 Under the condition of water depth of 0.3 m c The impact pressure duration curve comparing the numerical results simulated by the simulation device at the point with the measurement test data of the pressure sensor passing through this point Figure 12 Under the condition of water depth of 0.3 m d The impact pressure duration curve comparing the numerical results simulated by the simulation device at the point with the measurement test data of the pressure sensor passing through this point. Through simulation, it is found that the pressure value on the straight-wall structure shows fluctuating changes. According to the results of the impact pressure duration curve of the regular wave, the reasons for the pressure change are analyzed. It is found that it is affected by wave impact and water body inertia force, and the pressure reaches the maximum value in a short time and then decreases, increases again and finally decreases. That is, the first wave impact and the subsequent inertia effect lead to a rapid increase in pressure, followed by a decrease, and a secondary peak appears, forming a characteristic saddle-shaped pressure-time curve.

[0053] See Figures 13 - 18 , By changing the water depth to calculate the wave surface elevation and pressure change under the condition of 0.325 m, the obtained result diagram is as Figures 13 - 18 shown Figure 13 The impact pressure duration curve comparing the numerical simulation of the simulation device at the position of wave gauge G1 with the measurement experimental data of the wave gauge G1 for the wave surface elevation time history under the condition of water depth of 0.325 m Figure 14 The impact pressure duration curve comparing the numerical simulation of the simulation device at the position of wave gauge G2 with the measurement experimental data of the wave gauge G2 for the wave surface elevation time history under the condition of water depth of 0.325 m Figure 15 Under the condition of water depth of 0.325 m a The impact pressure duration curve comparing the numerical results simulated by the simulation device at the point with the measurement test data of the pressure sensor passing through this point Figure 16 Under the condition of water depth of 0.325 m b The impact pressure duration curve comparing the numerical results simulated by the simulation device at the point with the measurement test data of the pressure sensor passing through this point Figure 17 Under the condition of water depth of 0.325 m c The impact pressure duration curve comparing the numerical results simulated by the simulation device at the point with the measurement test data of the pressure sensor passing through this point Figure 18 Under the condition of water depth of 0.325 m dThe impact pressure duration curve obtained by comparing the numerical results simulated by the simulation device at a certain point with the measurement test data of the pressure sensor at that point further verifies the model accuracy of the simulation device and the calculation accuracy for different water depths.

[0054] See Figure 19 and Figure 20 In this embodiment, the time-varying curves of the pressure on the vertical-wall structure under two water depth conditions are calculated and compared with the test results. The results are as Figure 19 and Figure 20 shown. Figure 19 is the comparison diagram of the time-varying curve of the pressure on the vertical-wall structure and the test results under the water depth condition of 0.3 m. Figure 20 is the comparison diagram of the time-varying curve of the pressure on the vertical-wall structure and the test results under the water depth condition of 0.325 m. It can be seen from the figure that the overall shape of the pressure curve is in good agreement with the test results in most time periods, which indicates that the model of the simulation device has strong prediction ability under this condition. Generally speaking, the numerical simulation results of the simulation device can predict the test data well in some time periods.

[0055] In this embodiment, the wave development process and the wave surface change situation of the first two wave impacts in the simulation process of the simulation device are further visualized. The results are as Figure 21 and Figure 22 shown, where Figure 21 is the diagram of the first impact process and the change of the velocity field. Figure 22 is the second impact process and the change of the velocity field. By analyzing the breaking situation of the wave surface and the change of the velocity field, the relative angle between the wave crest surface and the vertical-wall structure and the relative height between the wave crest and the water surface at the wall are the main factors affecting the duration process of the wave impact pressure. Therefore, choosing a suitable position and height of the vertical wall in engineering will effectively reduce the damage of the impact to the structure. The smooth particle hydrodynamics simulation algorithm model used highlights its potential to accurately simulate the impact of waves on the structure, thus providing a reliable tool for engineering analysis and design optimization in marine and coastal environments and a powerful way to improve the design of coastal structures against wave impacts.

[0056] Among them, Figure 21 in (a) is the diagram of the change of the wave velocity field at 4.66 s after the first wave impact. Figure 21 in (b) is the diagram of the change of the wave velocity field at 4.72 s after the first wave impact. Figure 21 in (c) is the diagram of the change of the wave velocity field at 4.84 s after the first wave impact. Figure 21 in (d) is the diagram of the change of the wave velocity field at 5.14 s after the first wave impact. Figure 21 in (e) is the diagram of the change of the wave velocity field at 5.28 s after the first wave impact.Figure 21 In (f), it is the change diagram of the wave velocity field at 5.46 s after the first wave impact.

[0057] Immediately afterwards, Figure 22 In (a), it is the change diagram of the wave velocity field at 5.86 s after the second wave impact, Figure 22 In (b), it is the change diagram of the wave velocity field at 6.00 s after the second wave impact, Figure 22 In (c), it is the change diagram of the wave velocity field at 6.12 s after the second wave impact, Figure 22 In (d), it is the change diagram of the wave velocity field at 6.30 s after the second wave impact, Figure 22 In (e), it is the change diagram of the wave velocity field at 6.48 s after the second wave impact, Figure 22 In (f), it is the change diagram of the wave velocity field at 6.78 s after the first wave impact.

[0058] To sum up, for the wave impact process simulation system of a vertical wall structure disclosed in this embodiment, in view of the technical problems of the present invention, by setting up a collection device, the wave height data of water flow fluctuations and the pressure data at several sampling points on the vertical wall building can be obtained in real time. By setting up a simulation device to utilize the wave height data and pressure data obtained by the collection device, the pressure information at different heights of the vertical wall building when a regular wave impacts the vertical wall building can be obtained through the smoothed particle hydrodynamics (SPH) simulation algorithm. Since the SPH simulation algorithm can perform numerical model verification on the motion characteristics of regular waves and conduct numerical simulation of the wave impact on the vertical wall building, and can also calculate the wave surface elevation duration curve in front of and on the slope and the pressure values at different heights on the vertical wall building when a regular wave impacts, this algorithm can accurately simulate the propagation of regular waves and their impact on the vertical wall building, not only reducing the computational complexity, but also having good agreement with the experimental data, making the simulation effect effective. It can further reveal the key factors affecting the impact pressure and provide effective design optimization suggestions.

[0059] In the description of the embodiments of the present application, it should be noted that in the description of the present application, terms such as "inside" and "outside" indicating the direction or positional relationship are based on the direction or positional relationship shown in the drawings. This is only for convenience of description and does not indicate or imply that the device or component must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present application.

[0060] In the description of the present application, the descriptions with reference to terms such as "one embodiment", "some embodiments", "in this embodiment", "specific example", or "some examples" mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0061] As described above, the above is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed in the present application should be covered by the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A simulation system for the impact process of waves on a vertical wall structure, characterized in that include: The acquisition device is configured to obtain real-time wave height data of water flow fluctuations and pressure data at several sampling points on the vertical wall structure; The simulation device is electrically connected to the acquisition device and is configured to use the wave height data and pressure data obtained by the acquisition device to obtain pressure information at different heights of the straight-wall building when a regular wave impacts the straight-wall building through a smooth fluid particle fluid hydrodynamic simulation algorithm.

2. The impact process simulation system of a wave against a vertical wall structure according to claim 1, wherein The acquisition device includes at least one wave height meter G1 arranged in front of the slope, at least one wave height meter G2 arranged on the slope, and several pressure sensors arranged on the straight-wall building. All of the wave height meters G1, the wave height meters G2 and all of the pressure sensors are electrically connected to the simulation device.

3. The wave impact process simulation system for a straight wall structure according to claim 1 or 2, characterized in that The simulation device is configured to perform the following steps: A1: Formulate the integral approximation rule of the field function based on the kernel function approximation method; A2: Rewrite the fluid control equation according to the integral approximation rule to obtain the discrete form of the control equation; A3: rewrite the density diffusion equation according to the integral approximation rule to obtain the density diffusion term, and combine the density diffusion term with the discrete form of the control equation to obtain the hydrodynamic equation of the smooth fluid particle fluid; A4: Obtain the time integral format of the smooth fluid particle fluid hydrodynamic equation by a time integral format construction method; A5: Based on the time integration format, dynamic boundary conditions are introduced to obtain the definite form of the numerical differential equation; A6: constructing a numerical water tank based on the characteristic dimensions of the straight-walled building, and using a wave pusher plate to generate regular waves in the numerical water tank; A7: Based on the regular wave generated in step A6, different fluid particle sizes are selected to obtain time curves of the regular wave surface of different particle sizes, and these time curves are compared with the wave height data obtained by the acquisition device to select the optimal particle size in terms of accuracy and calculation time; A8: Simulate the wave impact of the regular wave with the optimal particle size on the straight-walled building in the numerical water tank, and substitute the wave height data and pressure data obtained by the acquisition device into the fixed-point form of the numerical differential equation to obtain the pressure information at different heights of the straight-walled building.

4. The impact process simulation system of a wave against a straight wall structure according to claim 3, characterized in that, The integral approximation rule includes: First, the field function, the derivative of the field function, or the field function and its derivative are approximated by an integral based on a smooth kernel function; the smooth kernel function is a quintic spline kernel function; Secondly, the water flow is discretized into a series of orthogonally distributed fluid particles, and the field function, the derivative of the field function, or the integral approximate representation of the field function and its derivative of each fluid particle is converted into a summation form through the numerical summation approximate representation method of adjacent fluid particles.

5. The impact process simulation system of a wave against a straight wall structure according to claim 4, characterized in that, The discrete form of the control equation includes: Momentum equation: , ， ， ， ； Monaghan equation: , ； Continuity equation: ; Where, representing fluid particles and adjacent fluid particles determining the viscous term; is the acceleration due to gravity; and represent fluid particles; represents the density of the fluid particles; represents the pressure of the fluid particles; represent the position of fluid particles; representing the flow velocity of fluid particles; representing a fluid particle and an adjacent fluid particle determined smooth kernel function; represents the smoothing length of the said smoothing kernel function; represents the speed of sound; represents the mass of the fluid particle; Represents the introduction of a correction factor; represent the derivative operation on the smooth kernel function ; Representative fluid particle Relative velocity with adjacent fluid particles ​ 6. The impact process simulation system of the wave on the straight wall structure according to claim 5, characterized in that, The density diffusion term is calculated as follows: ， ， Where, represent the proportionality coefficient; Representative fluid particle With the fluid particle Projection of the distance vector along the x-axis.

7. The impact process simulation system of a wave against a straight wall structure according to claim 6, characterized in that The time integration format is the Simpson numerical integration format.

8. The impact process simulation system of a wave against a vertical wall structure according to any one of claims 5-7, characterized in that, The regular wave is a second-order Stokes wave.

9. A method for simulating the impact process of waves on a vertical wall structure, characterized in that, A system for simulating a wave impact on a vertical wall structure according to any one of claims 1 to 8, comprising the following steps: S1: The wave height data of water flow fluctuations and the pressure data at several sampling points on the vertical wall building are obtained in real time through the acquisition device; S2: Using the wave height data and pressure data obtained by the acquisition device through the simulation device, the pressure information of different heights of the vertical wall type building when a regular wave impacts the vertical wall type building is obtained through the smoothed particle hydrodynamics simulation algorithm.

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