Hydrodynamic sediment physical model experiment method for simulating variable tide level combined wave action

Abstract

The invention discloses a hydrodynamic sediment physical model experiment method for simulating variable tide level combined wave action. The method comprises the following steps: building a physical model experiment system comprising an experiment water tank, a tide level simulation system, a wave generation system and a measurement system; determining a model tide level process and a wave element sequence according to the prototype environment data; calibration of control parameters of the tide level simulation system is carried out in an empty water tank state, and calibration of control parameters of the wave generation system is carried out according to different water depths and wave elements; after a bottom bed model is laid, the two systems are operated synchronously, the water level changes dynamically, corresponding waves are generated, and variable tide level and wave combined action simulation is achieved; and hydrodynamic force and bed topographic data are collected through the measuring system for analysis. Accurate combined simulation of dynamic sea level change and wave action is achieved, the sea level simulation system is simple in structure, low in cost and easy to install and control, the simulation precision of the complex water and sediment movement process is improved, and an economical and reliable experimental means is provided for coast engineering research.

Description

Technical Field

[0001] This invention belongs to the field of experimental technology of physical models of marine engineering, port channels and coastal geomorphology, and particularly relates to an experimental method for simulating the hydrodynamic sediment physical model of combined wave action with tidal level changes. Background Technology

[0002] In coastal and estuarine areas, the hydrodynamic environment is complex, with the periodic rise and fall of tides and the action of waves superimposed to jointly shape the transport, scouring, and deposition of sediment. Physical model experiments are an important means of studying such complex processes, predicting engineering effects, and environmental evolution. Accurately simulating the hydrodynamic sediment movement patterns under the combined action of changing tides and waves is crucial for this research.

[0003] Traditional physical modeling experiments, when simulating the effects of tides and waves, typically employ a static approach to tidal level simulation. Most experiments use fixed water levels to simulate high tide, low tide, or mean tide, failing to realistically reproduce the continuous and dynamic changes in tidal levels. The dynamic characteristics caused by tidal changes, such as beach submersion and exposure, and the channeling effect, are difficult to capture. Furthermore, the impact of tidal changes on wave propagation characteristics (such as wave height, wavelength, and breakwater location) and their combined effect on bottom shear forces is not fully considered. Due to the lack of precise water level control systems in experimental flumes, and the complexity and cost of adding such systems, experiments aiming to study the interaction between tidal levels and waves often treat tidal changes as either stepwise variations or crudely divide them into rising phases – high / low water levels – falling phases (with constant rates during rising and falling phases). This loses the natural sinusoidal nature of tidal changes, leading to distortions in the relevant physical processes. In summary, traditional experimental methods fail to fully incorporate the combined effects of tidal levels and waves when considering the initiation, transport, and settling of sediment, resulting in low accuracy in simulating sediment movement patterns and failing to provide accurate data for engineering design and ecological protection.

[0004] Therefore, developing a physical model experimental method that can easily and efficiently simulate the combined effects of dynamic tidal level changes and waves, and accurately reproduce the corresponding hydrodynamic and sediment transport processes, has significant theoretical value and engineering application needs. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention proposes an experimental method for simulating the hydrodynamic sediment physical model of combined tidal level and wave action, thereby resolving the issues present in the existing technologies.

[0006] To achieve the above objectives, this invention provides an experimental method for simulating the hydrodynamic sediment physical model of combined tidal level and wave action, comprising: A physical model experimental system is constructed, which includes an experimental water tank, a tide simulation system, a wave generation system, and a measurement system. Based on the prototype environment data, determine the tidal process and corresponding wave element sequence of the model experiment; In an empty tank state, the control parameters of the tide level simulation system are calibrated according to the tide level process, and the control parameters of the wave generation system are calibrated according to the different water depths corresponding to the tide level process and the wave element sequence. After laying the substrate model in the experimental tank, the tidal simulation system and the wave generation system are run synchronously according to the calibrated control parameters, so that the water level in the experimental tank changes dynamically according to the tidal process, and waves corresponding to the dynamic water level in real time are generated to realize the simulation of the combined effect of tidal change and waves; the hydrodynamic and substrate topographic data during the experiment are collected by the measurement system and analyzed.

[0007] Optionally, the tide simulation system includes a water storage system, a water pump group connecting the water storage system and the experimental water tank, a flow control unit located on the connecting pipeline, and a water level monitoring device located in the experimental water tank.

[0008] Optionally, the water storage system is a nested double-layered open water tank, including an inner water tank and an outer water tank surrounding the inner water tank; the pump set includes a main pump connected to an external water source and the inner water tank, an auxiliary pump located in the inner water tank and connected to the experimental water tank, and a drain pump located in the experimental water tank and connected to the outer water tank; the height of the inner water tank wall is higher than the height of the outer water tank wall, and the inner water tank is always kept full during operation, so that water exceeding its capacity overflows into the outer water tank; the bottom of the outer water tank is provided with a drain hole.

[0009] Optionally, the wave generation system includes a pusher-type wave generator located at one end of the experimental water tank; the measurement system includes a wave height meter, a current meter, and a topographic acquisition device for collecting bottom topographic data located in the experimental water tank.

[0010] Optionally, a connecting platform is laid at the bottom of the experimental water tank, the connecting platform containing connecting pipes, and the substrate model is laid on the connecting platform; the water level monitoring device is located in the water body behind the substrate model.

[0011] Optionally, when determining the tidal process and corresponding wave element sequence of the model experiment based on the prototype environmental data, the hydrodynamic scale is determined according to the gravity similarity criterion, and the prototype tidal level and wave data are converted into the tidal process and wave element sequence of the model experiment; based on the sediment movement characteristics of the prototype sea area, one of the Shields criterion and the dimensionless settling velocity criterion is selected to determine the sediment movement scale, and the experimental sand is selected according to the sediment movement scale.

[0012] Optionally, calibrating the control parameters of the tide level simulation system includes: dividing the period of the tide level process into multiple continuous time segments, with the water level change within each time segment set to a linear change; repeatedly testing the required tide level change rate for each time segment by adjusting the flow control unit of the tide level simulation system to obtain the control parameters corresponding to that tide level change rate; and conducting a complete test and verification of the entire tide level cycle based on the control parameters corresponding to each time segment.

[0013] Optionally, calibrating the control parameters of the wave generation system includes: adjusting the parameters of the wave generation system according to different water depths and corresponding wave elements corresponding to the tidal process, performing repeated tests multiple times, obtaining wave generation control parameters corresponding to the corresponding water depths and wave elements, and recording the relationship between the wave generation parameters and the wave parameters.

[0014] Compared with the prior art, the present invention has the following advantages and technical effects: (1) High simulation accuracy: By precisely controlling the tide level simulation system and the wave generation system, it is possible to accurately simulate the complex combined effects of tide level and waves in the actual sea area. Combined with high-precision measuring instruments and data analysis methods, it greatly improves the simulation accuracy of hydrodynamic sediment movement laws and provides more reliable data support for engineering design and scientific research.

[0015] (2) Comprehensive simulation of combined effects: This experimental method can simulate the combined effects of waves and tides at different phases and intensities, fully considering the mutual influence and coupling relationship between the two, making the experimental results closer to the hydrodynamic sediment movement in the actual marine environment, and providing an effective experimental means for in-depth research on the hydrodynamic sediment interaction mechanism.

[0016] (3) Low cost and strong adaptability: The tidal change system in the experimental device is simple to set up, low cost and easy to install. It can realize high-precision tidal control function, which makes this experimental method highly adaptable. It can flexibly adjust the experimental parameters and model similarity scale according to different research purposes and actual needs, simulate hydrodynamic sediment movement under different sea areas and different engineering conditions, and provide an experimental platform for research in various fields such as water conservancy projects and coastal engineering. Attached Figure Description

[0017] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a flowchart illustrating the overall process of an embodiment of the present invention. Figure 2 This is a schematic diagram of the experimental system structure according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the tide level change curve and wave parameter change in an embodiment of the present invention; Figure 4 This is a schematic diagram illustrating the changes in the substrate according to an embodiment of the present invention; 1. Water tank; 2. Push-plate wave generator; 3. Tidal level simulation system; 4. Sandy coastline profile model; 5. Wave height meter - wave recorder; 6. Acoustic Doppler current meter; 7. Wave height meter - water level recorder; 8. High-speed camera; 3.1. Reservoir; 3.2. Double-layer water storage tank; 3.3. Water pump; 3.4. Flow meter; 3.5. Valves; 3.6. Connecting device. Detailed Implementation

[0018] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0019] Example 1 like Figure 1 As shown, this embodiment provides an experimental method for simulating the hydrodynamic sediment physical model of tidal level combined with wave action, including: Step S1: Experimental system construction; The physical model experimental system includes: (1) Experimental water tank: A rectangular water tank with a certain length, width and depth. A wave generator is set at one end of the water tank and a wave damping device is set at the other end to simulate the generation and propagation of waves and reduce the interference of wave reflection on the experiment. A low-height connecting platform is laid at the bottom, containing multiple PVC pipes to connect the water level changes before and after the bottom bed model (the connecting module of the tide level simulation system). The bottom bed model is laid on the platform according to the prototype landform and scaled down. The material is mud and sand that meet the requirements of specific gravity and particle size scale.

[0020] Furthermore, the connecting platform laid at the bottom covers the width of the water tank in width (parallel to the wave-making plate), is longer than the entire substrate model and its transport range in length (perpendicular to the wave-making plate), and has sufficient initial length (usually more than 2-3 times the wavelength) in the wave-facing direction (in front of the substrate model) to avoid the water flow entering and leaving the port changing the water flow structure and thus affecting the substrate changes. The port behind the substrate model needs to maintain a certain space with the wave-damping equipment to accommodate water pumps and other devices.

[0021] (2) Tide level simulation system: It consists of three modules: an upward and downward water level control system, and a connecting system at the bottom of the tank. These include a water storage system located at one end of the tank, a water pump, a water delivery pipe, a flow meter, valves, and a water level monitoring device. The upward and downward water pumps control the inflow and outflow of water into the tank, the water level monitor tracks water level changes, and the pump flow meter and valve openings control the rate of upward and downward water level movement, thus achieving continuous and precise rise and fall of the water level within the model and simulating dynamic tidal curve changes.

[0022] The water storage system consists of a nested double-layered open water tank with drainage holes placed outside the water tank and a laboratory reservoir. The double-layered water tank is used as a relay storage unit for water intake and drainage, while the laboratory reservoir is the source water supply unit and drainage collection unit. The water pumps are divided into main inlet pumps, auxiliary pumps, and drainage pumps. The main pumps have high power and a large head, and are responsible for introducing water from the reservoir into the inner tank of the double-layered water storage unit. The auxiliary pumps have low power and a small head, and are easy to control in terms of flow rate; they are placed in the inner tank and pump water directly into the water tank. The drainage pumps are placed directly in the water tank, located between the rear port of the connecting platform and the wave-damping device, and pump water out to the outer tank of the double-layered water tank system. The nested double-layered water tank system has an inner tank that is taller than the outer tank. The inner tank receives water pumped from the reservoir and is always kept at full capacity. Water exceeding its capacity overflows into the outer tank. At this point, the pump in the inner tank maintains a stable water level, ensuring consistent pumping efficiency. The outer tank has a drain hole at its bottom, connecting to the reservoir below the laboratory to drain water back into the reservoir. The water level sensor is located in the water body between the back of the substrate model and the wave-damping device. The water body here is stable because the substrate isolates waves, making it suitable as a water level observation point. The flow meter and valve are installed on the water delivery pipe connecting the inlet auxiliary pump and the water tank and the outlet pump and the water tank. The relationship between the flow meter and valve opening is determined in advance after the tidal level system is installed and verified by repeated tests. Before the test begins, the change in valve opening is confirmed according to the needs of tidal level changes. (3) Wave generation system: including a push plate type wave generator set at the other end of the water tank. By adjusting the stroke, frequency and phase parameters of the wave generator, waves with different wave heights, periods and directions are generated. The parameters of the wave generator are calibrated and optimized to ensure that the generated waves meet the experimental requirements.

[0023] (4) Measurement System: This includes wave height meters, flow velocity meters, turbidity meters or concentration meters (optional) arranged within the model, as well as terrain acquisition equipment such as laser scanners and cameras. Wave height meters, flow velocity meters, pressure sensors (optional), and sediment concentration meters (optional) are installed in the water tank to measure wave parameters, water flow velocity, water pressure (optional), and sediment concentration (optional) at different locations. A laser scanner is placed above the water tank or a camera is placed on the side of the water tank to measure the bottom topographic data. All instruments and equipment are calibrated and adjusted to ensure their measurement accuracy and reliability.

[0024] like Figure 2 As shown, this embodiment was implemented in a wave tank 30 meters long, 0.6 meters wide, and 1 meter high. A servo motor-driven pusher-type wave generator 2 was installed at one end of the tank 1, and a tide level simulation system 3 was installed at the other end, including a water storage system (reservoir 3.1, double-layered water tank 3.2), a water pump 3.3, a flow meter 3.4, valves 3.5, and a connecting device 3.6. A connecting platform (i.e., connecting device 3.6) was laid at the bottom of the tank 1, on which a sandy coastline profile model 4 was arranged according to a geometric scale. The model sand used was natural sand. Multiple wave height meters and two acoustic Doppler current meters (ADVs) 6 were arranged along the tank, with one wave height meter positioned behind the model for water level observation. During the experiment, a high-speed camera 8 was used to observe the topographic and liquid level changes throughout the experiment. Before the experiment, the instruments and equipment underwent multiple repeatability tests to ensure the stability and consistency of the measurement data.

[0025] Step S2: Determining and calibrating experimental parameters; Environmental parameter collection for the experimental prototype: Based on the tidal level data (determined by tide gauges, tide tables, etc.) and wave data (observed by buoys, radar, remote sensing, etc.) of the study area (prototype), data such as tidal range, tidal period, wave height, wave period, and wave direction are obtained; sediment samples are collected from the actual study area to determine parameters such as sediment particle size distribution, density, and bulk density.

[0026] Specifically, based on tidal data observed at the tide gauge station and wave data observed by buoys in the study area (prototype), the average tidal range in the study area during the study period was approximately 2.2 m, with a period of approximately 25 hours, a wave height of 4 m, and a wave period of 7.8 s. Sediment samples were collected from the actual study area, and the particle size distribution was determined using a sieve or laser particle size analyzer. The density of the sediment was determined using the hydrostatic bottle method, and the dry bulk density was determined using the ring sampler method. The measurements showed that the average particle size of the sediment used in the experiment was 0.08 mm, and the density was 2.53 g / cm³. 3 The dry bulk density is 1.51 g / cm³. 3 .

[0027] Model similarity design: Based on the hydrodynamic conditions, sediment properties, and topography of the actual engineering or research area (prototype), and combined with laboratory conditions (flue size, wave-generating equipment capacity, sediment materials, etc.), the scale of the experimental model is determined. Following the principle of similarity, the hydrodynamic scale and sediment movement scale of the experimental model are determined to ensure that the experimental model accurately reflects the hydrodynamic and sediment movement patterns of the prototype.

[0028] The hydrodynamic scale is usually determined based on the gravitational similarity criterion to make the Frod number of the experimental conditions equal to the Frod number of the prototype hydrodynamic conditions.

[0029] The sediment ratio is usually determined based on the sediment transport characteristics under hydrodynamic conditions in the prototype area. For beaches where bedload transport is dominant, the sediment ratio usually satisfies the Shields criterion, meaning that the Shields number formed by the hydrodynamic and sediment parameters under experimental conditions is equal to the Shields number of the prototype. For beaches where suspended sediment transport is dominant, the sediment ratio usually satisfies the dimensionless settling velocity criterion, meaning that the Gourry number (also known as the Dean number) formed by the hydrodynamic and sediment parameters under experimental conditions is equal to the Gourry number of the prototype.

[0030] For sediment transport experiments, it is recommended to use natural sand first at an appropriate scale, and not lightweight model sand, such as fly ash, because its specific gravity is lower than that of water while that of natural sand is higher than that of water and they have different physical properties, which may distort the characteristics of sediment movement.

[0031] Furthermore, hydrodynamic sediment experiments involve determining multiple scales, which require adjustments based on various conditions, such as compromises between the hydrodynamic scale and the sediment scale.

[0032] Specifically, based on the hydrodynamic conditions, sediment properties, and topography of the actual engineering or research area (prototype), and combined with laboratory conditions, the geometric scale is determined to be 1:25, the time scale to be 1:5, and the sediment transport scale to be 1:5. Following the principle of similarity, the hydrodynamic scale and sediment transport scale of the experimental model are determined to ensure that the experimental model accurately reflects the hydrodynamic and sediment transport patterns of the prototype. Based on the principle of similarity, various parameters of the experimental model are converted and designed to ensure that the experimental model accurately simulates the hydrodynamic and sediment transport patterns of the prototype. For example, the average water depth in the actual engineering area is 13.8 meters; according to the geometric scale, the corresponding water depth in the experimental tank should be 55 centimeters, with a tidal range of 0.08 meters, a tidal period of 5 hours, a wave height of 0.16 meters, and a wave period of 1.56 seconds. The main sediment transport type in the actual engineering area is suspended sediment transport, with a median sediment particle size of 0.8 mm; according to the sediment transport scale, the median sediment particle size in the experimental model is 0.19 mm.

[0033] Determination of tidal and wave parameters: Based on the tidal and wave data of the prototype sea area, the tidal process for the model experiment is determined. and the wave element sequence at the corresponding time (such as significant wave height) Spectral peak period , wave direction Based on the model's hydrodynamic scale, the model tidal process that needs to be reproduced in the model experiment is calculated. And the wave element sequence of the model.

[0034] Selection of experimental sand: Based on the sediment characteristic parameters of the prototype sea area, the parameters of the experimental sand are calculated based on the sediment similarity criterion, and the sediment with key parameters (such as median particle size, particle size sorting degree, etc.) that meet the requirements are selected.

[0035] Tidal level change rate determination: based on the model tidal level process The entire tidal cycle is divided into several equal-time segments, typically 12-18 segments. The water level in each segment maintains a linear change, with the level difference having minimal impact on wave generation. Before the formal experiment, the relationship between the water level change rate (flow rate) of each segment and the valve opening of the tidal system needs to be verified. Water level observation devices are installed at multiple locations within the empty tank. The rate of tidal change is altered by changing the valve opening to meet the needs of each tidal segment. The measurement of the relationship between the water level change rate and valve opening for each segment is repeated three times. After obtaining the valve opening corresponding to each tidal change segment within the entire tidal cycle, the valve openings of each segment are integrated, and the change in the entire tidal cycle is tested, repeated three times.

[0036] Furthermore, during the tidal level calibration process, water level monitoring devices are installed at multiple locations to determine whether water level changes at each location are synchronized. Typically, if the bottom connecting system has a sufficiently large diameter and is free of blockages, water level changes throughout the entire tank will be synchronized.

[0037] Specifically, multiple wave height meters / water level recorders (7) are arranged inside the empty water tank as water level observation devices, and flow meters (3.4) on the water supply pipe measure the inflow and outflow rates. Based on a tidal range of 0.08m and a tidal cycle of 5h, a sinusoidal model of tidal level changes is generated. The entire tidal level change cycle is divided into 16 equal-time segments, with the water level changing linearly in each segment. Based on calculations, the relationship between four sets of flow rate changes and the valve opening of the tidal level system needs to be calibrated and confirmed, specifically ±1.51 × 10⁻⁶. -4 ±1.07×10 -4 ±7.1×10 -5 ±2.7×10 -5m / s (+: water flows into the tank, water level rises; -: water flows out of the tank, water level falls), repeated 3 times. After confirming the valve opening corresponding to each tidal level change, the valve opening is changed by 3.5 degrees at each time point to meet the flow rate required for the next tidal level change. The tidal level change is tested throughout the entire cycle, repeated 3 times. The wave height gauges at different locations show that the water level changes at each location are synchronized, the bottom connection system is operating normally, and the experimental requirements are met.

[0038] Wave Calibration: Under the same wave parameters, water depth affects the setting of wave generator parameters. Therefore, the wave generator parameters need to be calibrated at different tidal levels during the experiment. Based on the previously defined tidal level variation segments and their corresponding wave parameters, the waves corresponding to each segment of the entire tidal cycle are calibrated. Wave observation equipment is set up at multiple locations within the empty tank. By changing the stroke, frequency, phase, and other parameters of the wave generator, the wave parameters within each tidal level segment are made to meet the experimental requirements. This process is repeated three times, and the relationship between the wave generator parameters and the wave parameters is recorded.

[0039] Specifically, wave height meters and wave recorders (5) were installed at multiple locations within the empty water tank to observe wave data. The experimental model had a wave height of 0.16 m and a period of 1.56 s. Since each tidal segment symmetrically repeats itself during actual tidal changes, wave parameters within eight tidal segments needed calibration. By changing the stroke, frequency, and phase parameters of the pusher-type wave generator (2), the wave parameters within each tidal segment were made to meet the experimental requirements of a wave height of 0.16 m and a period of 1.56 s. This process was repeated three times, and the relationship between the wave generator parameters and the wave parameters was recorded.

[0040] Step S3: Experiment run; Initial conditions were set: Using the selected experimental sand, a substrate model 4 with an initial slope of 1 / 12 was laid out on the connected platform according to the geometric scale. The initial tide level was set to 0.55m, and the initial wave parameters were set to wave height of 0.16m and period of 1.56s. The tide level system and wave generator were adjusted to bring the water tank to the set initial conditions.

[0041] Combined Effect Simulation: The tidal level simulation system and wave generation system are activated, and the combined effect of changing tidal levels and waves is simulated according to pre-set steps. During the experiment, the tidal level simulation system adjusts the valve opening at each node based on the actual tidal level changes to realize the rise and fall of the tidal level. The wave generation system adjusts the parameters of the pusher-type wave generator 2 in real time according to experimental requirements to generate waves with different wave heights, periods, and directions. Simultaneously, various measuring instruments installed in the water tank are used to monitor changes in parameters such as tidal level, waves, and water flow velocity in real time. Based on the real-time monitoring data, the parameters of the tidal tank and wave generator are dynamically adjusted to ensure the stability and accuracy of experimental conditions, such as... Figure 3The figure shows the tidal level and wave height variation sequences for two operating conditions. The upper part is the tidal level variation time series for the two operating conditions, and the lower part is the wave height variation time series for the two operating conditions.

[0042] Data Acquisition and Recording: Experimental data, including tide level, wave parameters, and water flow velocity, were collected at 0.1-second intervals using various measuring instruments installed in the water tank. Simultaneously, three high-speed cameras (8) recorded images of substrate changes and sediment movement at 10 frames per second. The cameras had resolutions of one 4096×4096 pixel camera and two 2048×2048 pixel cameras, clearly capturing details of sediment movement. The collected data and images were transmitted in real-time to a computer via a data acquisition card and stored in a dedicated database. A connection between image coordinates and world coordinates was established using a pre-set calibration board, and data analysis software was used for processing and preliminary analysis. During data acquisition, abnormal data was marked and recorded for subsequent analysis and processing.

[0043] Step S4: Specific methods for analyzing experimental results; Hydrodynamic characteristics analysis: Data analysis software was used to process and analyze the collected wave height, flow velocity, and other data. The distribution of wave height and flow velocity along the length of the channel was plotted, and the distribution characteristics of wave height and flow velocity were analyzed to study the changes in flow regime under different tidal levels and wave conditions. For example, by analyzing the wave height distribution curves at different times, it was found that during the rise of the tidal level, the wave-breaking zone may undergo a leapfrog migration as the water level rises. Research on Sediment Movement and Subsoil Change Patterns: This study analyzes the initiation, transport, and sedimentation processes of sediment using images recorded by high-speed cameras. Image processing software is used to analyze the images, identifying the trajectories and velocities of sediment particles, and investigating the relationship between sediment movement and hydrodynamic conditions. Observations of subsoil characteristics are conducted to study key geomorphic parameters, such as the elevation and location of sandbar crests, and their variation with tidal levels. For example, analysis of sediment movement images reveals that sediment movement begins when the water flow velocity reaches [X] cm / s. Analysis of sandbar crest location data establishes an empirical formula relating the response coefficient to environmental parameters, which is then substituted into a model to predict the response. Figure 4 The figure shows the actual response and predicted values ​​at the top of the sandbar.

[0044] Model Validation and Optimization: The experimental results are compared and analyzed with field observation data from actual engineering projects or research areas. The consistency of experimentally measured tide levels, wave parameters, and water flow velocities is compared with field observation data, and statistical analysis methods are used to calculate the errors between the two. Based on the comparison results, the experimental model is optimized and improved. For example, if a large deviation is found between the experimentally measured tide level and the field-observed tide level, the cause may be an unreasonable parameter setting in the tide level simulation system. The parameters of the tide level simulation system are adjusted and optimized, and the experiment is repeated until the experimental results show good consistency with the field observation data, thereby improving the accuracy and effectiveness of the experimental simulation.

[0045] The above embodiments demonstrate that the method of the present invention can reveal the complex water and sediment response mechanism under the combined action of tidal level and waves in greater detail.

[0046] The above are merely preferred embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An experimental method for simulating the hydrodynamic sediment physical model of combined tidal level and wave action, characterized in that, Includes the following steps: A physical model experimental system is constructed, which includes an experimental water tank, a tide simulation system, a wave generation system, and a measurement system. Based on the prototype environment data, determine the tidal process and corresponding wave element sequence of the model experiment; In an empty tank state, the control parameters of the tide level simulation system are calibrated according to the tide level process, and the control parameters of the wave generation system are calibrated according to the different water depths corresponding to the tide level process and the wave element sequence. After laying the substrate model in the experimental tank, the tidal simulation system and the wave generation system are run synchronously according to the calibrated control parameters, so that the water level in the experimental tank changes dynamically according to the tidal process, and waves corresponding to the dynamic water level in real time are generated to realize the simulation of the combined effect of tidal change and waves; the hydrodynamic and substrate topographic data during the experiment are collected by the measurement system and analyzed.

2. The experimental method for simulating the hydrodynamic sediment physical model of combined tidal level and wave action according to claim 1, characterized in that, The tide simulation system includes a water storage system, a water pump group connecting the water storage system and the experimental water tank, a flow control unit located on the connecting pipeline, and a water level monitoring device located in the experimental water tank.

3. The experimental method for simulating the hydrodynamic sediment physical model of combined tidal level and wave action according to claim 2, characterized in that, The water storage system is a nested double-layered open water tank, including an inner water tank and an outer water tank surrounding the inner water tank; the pump set includes a main pump connected to an external water source and the inner water tank, an auxiliary pump located in the inner water tank and connected to the experimental water tank, and a drain pump located in the experimental water tank and connected to the outer water tank; the height of the inner water tank wall is higher than that of the outer water tank wall, and the inner water tank is always kept full during operation, so that water exceeding its capacity overflows into the outer water tank; the bottom of the outer water tank is provided with a drain hole.

4. The experimental method for simulating the hydrodynamic sediment physical model of tidal level combined with wave action according to claim 1, characterized in that, The wave generation system includes a pusher-type wave generator located at one end of the experimental water tank; the measurement system includes a wave height meter, a current meter, and a topographic acquisition device for collecting bottom topographic data located in the experimental water tank.

5. The experimental method for simulating the hydrodynamic sediment physical model of combined tidal level and wave action according to claim 2, characterized in that, A connecting platform is laid at the bottom of the experimental water tank, the connecting platform containing connecting pipes, and the substrate model is laid on the connecting platform; the water level monitoring device is located in the water body behind the substrate model.

6. The experimental method for simulating the hydrodynamic sediment physical model of combined tidal level and wave action according to claim 1, characterized in that, When determining the tidal process and corresponding wave element sequence of the model experiment based on the prototype environmental data, the hydrodynamic scale is determined according to the gravity similarity criterion, and the prototype tidal and wave data are converted into the tidal process and wave element sequence of the model experiment. Based on the sediment movement characteristics of the prototype sea area, one of the Shields criterion and the dimensionless settling velocity criterion is selected to determine the sediment movement scale, and the experimental sand is selected according to the sediment movement scale.

7. The experimental method for simulating the hydrodynamic sediment physical model of tidal level combined with wave action according to claim 1, characterized in that, The calibration of the control parameters of the tide level simulation system includes: dividing the period of the tide level process into multiple continuous time segments, and setting the water level change in each time segment to a linear change; for the required tide level change rate for each time segment, repeatedly testing by adjusting the flow control unit of the tide level simulation system to obtain the control parameters corresponding to the tide level change rate; and conducting a complete test and verification of the entire tide level cycle based on the control parameters corresponding to each time segment.

8. The experimental method according to claim 1, characterized in that, The calibration of the control parameters of the wave generation system includes: adjusting the parameters of the wave generation system according to the different water depths and corresponding wave elements corresponding to the tidal process, performing repeated tests to obtain the wave generation control parameters corresponding to the corresponding water depths and wave elements, and recording the relationship between the wave generation parameters and the wave parameters.

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