A method and system for simulating a composite tsunami surge wave based on dam-break water flow

Abstract

The application provides a dam-break flow-based composite tsunami surge wave simulation method and system, and relates to the technical field of coastal engineering and disaster prevention and mitigation physical model experiment. The method comprises the following steps: at least two gates are arranged in a fluid channel to divide the fluid channel into at least three independent water storage areas, and the initial water levels of the water storage areas are configured to be different; the characteristic wave velocity of the fluid wave in each water storage area is calibrated through pre-operation test; the opening delay time of the subsequent gate is determined based on the target composite position and the characteristic wave velocity; and the gates are controlled to open according to the preset opening time sequence and the opening delay time to generate a composite wave at the target composite position. The application realizes accurate superposition of multiple fluid waves at a predetermined position, and truly restores the complex wave form evolution mechanism under extreme transient hydrodynamic conditions.

Description

Technical Field

[0001] This application relates to the field of experimental technology of physical models for coastal engineering and disaster prevention and mitigation, specifically to a method and system for simulating composite tsunami surge waves based on dam-break water flow. Background Technology

[0002] In coastal engineering and disaster prevention and mitigation research, physical model experiments are crucial for revealing the mechanisms by which extreme waves affect shorelines. Existing wave-generating techniques typically use wave generators to produce isolated waves to approximate long-period waves such as tsunamis. However, isolated waves have short effective wavelengths and limited energy carrying capacity per wave, making it difficult to accurately reproduce the wall-of-water effect and long-duration inundation plateau phase of strong nearshore swells. While swells generated by dam-break flows more closely resemble real tsunamis in their transient high-energy characteristics, traditional single-break devices can only produce uniform swells of a single intensity. They cannot simulate the superimposed effects of multiple waves continuously impacting a real disaster, nor can they reproduce complex transient waveforms such as N-shaped waves with leading receding water characteristics. This lack of simulation capability makes it difficult for experiments to accurately reflect the evolution of shoreline topography under extreme hydrodynamic conditions, limiting the reliability of disaster prevention and mitigation designs. Summary of the Invention

[0003] To address the problem that existing technologies struggle to accurately simulate complex transient composite waveforms such as multi-wave superposition and leading receding water in physical models, this application proposes a composite tsunami surge simulation method and system based on dam-break flow, achieving high-fidelity reproduction of real extreme hydrodynamic characteristics.

[0004] The technical means employed in this invention are as follows: A method for simulating complex tsunami surge waves based on dam-break flow includes the following steps: At least two gates are set in the fluid channel to divide the fluid channel into at least three independent water storage areas, and each water storage area is configured with a different initial water level; The characteristic wave velocity of the fluid wave in each of the aforementioned water storage areas was calibrated through pre-run tests. Based on the target composite position and the characteristic wave velocity, determine the opening delay time of the subsequent gate among the at least two gates; The gates are opened according to a preset opening sequence and an opening delay time to generate composite waves at the target composite position.

[0005] Furthermore, the at least three independent water storage areas include a first water storage area, a second water storage area, and a third water storage area arranged sequentially along the extension direction of the fluid channel; The step of controlling the opening of each gate according to the preset opening sequence and the opening delay time includes: first opening the gate near the third water storage area to generate a leading wave, and then opening the gate near the first water storage area to generate a main wave peak, so that the main wave peak meets and superimposes with the leading wave at the target composite position.

[0006] Furthermore, the initial water levels for each of the aforementioned water storage areas are not entirely the same, including: Water is injected into the first water storage area to the first initial water level, water is injected into the second water storage area to the second initial water level, and water is injected into the third water storage area to the third initial water level; Wherein, the first initial water level is greater than the third initial water level, and the third initial water level is greater than the second initial water level, so as to generate an N-shaped wave with leading receding water characteristics in the fluid channel.

[0007] Furthermore, the characteristic wave velocity of the fluid wave in each of the aforementioned water storage areas is calibrated through pre-run tests, including: While keeping the initial water level boundaries of each of the aforementioned water storage areas unchanged, the gates of the areas to be calibrated are opened individually to release the initial surge wave; Record the opening signal time of the gate in the area to be calibrated, and the arrival time of the wavefront of the initial surge to the preset monitoring section. The characteristic wave velocity is calculated based on the spatial distance between the preset monitoring section and the gate of the area to be calibrated, and the time difference between the arrival time and the opening signal time.

[0008] Furthermore, the preset monitoring section includes a first monitoring section located at the gate of the area to be calibrated, and a second monitoring section located at the target composite position; wherein, the first monitoring section is used to calibrate the characteristic wave velocity of the main wave peak; The calculation of the characteristic wave velocity includes: The characteristic wave velocity of the initial surge wave is calculated based on the following formula. :

[0009] in, This indicates the spatial distance between the gate in the area to be calibrated and the second monitoring section. This indicates the arrival time of the initial surge wave's wavefront at the second monitoring section. This indicates the opening signal time of the gate to be calibrated.

[0010] Further, based on the target composite position and the characteristic wave velocity, the opening delay time of the subsequent gate among the at least two gates is determined, including: Calculate the first propagation time of the first fluid wave generated by the first gate that opens before the subsequent gate, which of the at least two gates, to the target composite position; Calculate the second propagation time of the second fluid wave generated by the subsequent gate to the target composite position; The difference between the first propagation time and the second propagation time is determined as the opening delay time of the subsequent gate; wherein the first propagation time is greater than the second propagation time.

[0011] Furthermore, the water storage area between the first opened gate and the subsequent gate in the at least three independent water storage areas is an intermediate transition area. When the composite wave has leading receding water characteristics, i.e., an N-shaped waveform with a drop in water level followed by a rise in wave crest, and the target composite position is located within the intermediate transition area, the opening delay time... Calculated using the following formula:

[0012] in, Indicates the length of the intermediate transition region. This indicates the distance the second fluid wave travels within the intermediate transition region. This represents the characteristic wave velocity of the first fluid wave within the intermediate transition region. This indicates the characteristic wave velocity of the second fluid wave within the intermediate transition region.

[0013] Furthermore, the method also includes: A water level monitoring array, a flow velocity monitoring array, and a global visual observation system are arranged in the fluid channel and on the target slope within the fluid channel. The instantaneous wave height and local flow velocity of the composite wave are collected in real time by the water level monitoring array and the flow velocity monitoring array, and the macroscopic physical evolution process of the composite wave is recorded by the global visual observation system.

[0014] Furthermore, the method also includes: After the composite wave reaches the boundary of the fluid channel, each of the gates is closed to prevent interference from reflected waves; After the water in the fluid channel has settled, erosion depth and topographic evolution profile data of the target slope are collected.

[0015] This invention also discloses a composite tsunami surge simulation system based on dam-break flow, comprising: A fluid channel, wherein a target slope is provided within the fluid channel; At least two gates are provided in the fluid channel to divide the fluid channel into at least three independent water storage areas; A monitoring array is arranged in the fluid channel and the target slope. A control module, communicatively connected to the at least two gates and the monitoring array, is configured to execute a composite tsunami surge simulation method based on dam-break flow as described in any of the preceding claims.

[0016] Compared with the prior art, the present invention has the following advantages: The method and system for simulating complex tsunami surge waves based on dam-break flow provided in this application divides the fluid channel into multiple independent water storage areas by setting at least two gates and configuring differentiated initial water levels, thus constructing the physical potential energy basis for generating complex complex waves. The opening delay time of subsequent gates is calculated by combining the actual characteristic wave velocity calibrated by pre-operation test, which effectively eliminates theoretical analysis errors and realizes microsecond-level precise superposition of multiple fluid waves at the target composite position.

[0017] Compared to traditional single dam failure or wavemaker simulation methods, this application can not only generate positive surge waves with long-duration high-energy plateau periods, but also flexibly simulate the superposition effect of multiple waves chasing each other in the same direction and N-shaped waves with leading receding characteristics. It realistically restores the complex waveform evolution mechanism under extreme transient hydrodynamic conditions, significantly improving the physical model experiment's ability to reproduce real disaster scenarios and its data support value.

[0018] Furthermore, this application divides the fluid channel into three independent storage zones using a dual-gate system. Each storage zone can be independently set with different initial water depths, thereby enabling flexible combinations and dynamic control of different Froude numbers within the same experimental system. Specifically, by adjusting the water depths of the upstream main reservoir area, the intermediate transition zone, and the downstream propagation zone, low-Froude number non-breaking swells can be generated in the deep water area, evolving into high-Froude number breaking swells as they approach the shallow water slope area, autonomously causing abrupt changes in wave morphology and intensity during propagation. This dynamic adjustment capability realistically reflects the physical process in the real ocean environment where tsunami waves propagate from the deep sea to the nearshore, causing a dramatic evolution in Froude number and a gradual transition in wave morphology from wavy swells to breaking swells due to the gradually decreasing water depth. This overcomes the inherent limitation of single dam-break systems, which can only generate uniform swells of constant intensity and cannot simulate the morphological evolution of waves during propagation, providing richer and more realistic experimental data support for coastal engineering and disaster prevention and mitigation. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a flowchart of a composite tsunami surge simulation method based on dam-break water flow according to an embodiment of this application; Figure 2 This is a schematic diagram of the single-gate dam failure simulation experimental device according to an embodiment of this application; Figure 3 This is a schematic diagram of the structure of the dual-gate dam failure simulation experimental device according to an embodiment of this application; Figure 4 It is a wave height time history diagram of an isolated wave waveform generated by a wave generator using traditional methods; Figure 5 These are time history curves of surge wave heights for single dam-break surges at different Froude numbers (Fr=1.1-1.5) according to embodiments of this application. Figure 6 This is a time-history curve of single dam-break surge wave height for different Froude numbers (Fr=1.6-2.0) according to embodiments of this application; Figure 7 This is a graph showing the time-varying wave height of a double dam failure under different Froude number conditions according to an embodiment of this application. Figure 8 This is a time-history curve of the simulated N-shaped wave height of a double-dam failure according to an embodiment of this application.

[0021] Among them, 1. Camera; 2. Ultrasonic wave height meter; 3. Point flow velocity meter; 4. CBG wave height meter; 5. Ludong wave height meter; 6. Profile flow velocity meter; 7. Gate. Detailed Implementation

[0022] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0023] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0024] Example 1 like Figure 1 As shown, this embodiment provides a method for simulating complex tsunami surge waves based on dam-break flow. This method constructs independent potential energy storage units through multi-stage gates and combines this with time-series control based on pre-tested and calibrated actual wave velocities, thereby accurately generating complex transient waveforms that conform to real physical laws at the target location. It should be understood that although this embodiment uses the simulation of tsunami waves and slope sediment erosion as an example, this method is also applicable to other coastal engineering or water conservancy disaster prevention and mitigation experimental scenarios that require simulating long-period, strongly nonlinear complex waves.

[0025] Specifically, the simulation method includes the following steps: Step S1: Set at least two gates in the fluid channel to divide the fluid channel into at least three independent water storage areas, and configure different initial water levels for each water storage area.

[0026] In this embodiment, as Figure 3 As shown, the fluid channel is a transparent glass tank with a target slope at its downstream end to simulate a natural bank slope. By setting a leading wave gate and a main wave crest gate, the fluid channel is sequentially divided into a first, second, and third water storage area along its extension direction. The first water storage area corresponds to the upstream main reservoir area, the second water storage area corresponds to the intermediate transition zone, and the third water storage area corresponds to the downstream propagation zone. This partitioned design allows each area to independently store different levels of potential energy, providing a physical basis for the subsequent generation of composite waves with specific morphological characteristics. The initial water level of each water storage area is configured differently according to the type of the target waveform. For example, when simulating a unidirectional chasing wave, a stepped decreasing water level is typically used; while when simulating an N-shaped wave, a water level distribution with high levels at both ends and low levels in the middle is configured.

[0027] Step S2: Calibrate the characteristic wave velocity of the fluid wave in each water storage area through pre-run tests.

[0028] Since dam-break flow is a typical unsteady flow, its wave velocity is significantly affected by water depth, bed friction, and boundary conditions, and calculations using purely theoretical formulas often have large deviations. Therefore, this embodiment uses a pre-operation test to obtain the measured wave velocity. Specifically, while keeping the initial water level boundaries of each reservoir area constant, the gates of the area to be calibrated are opened individually to release the initial surge wave. A monitoring array arranged in the fluid channel records the wavefront propagation time and distance, thereby calculating the true characteristic wave velocity under this condition.

[0029] Step S3: Based on the target composite position and characteristic wave velocity, determine the opening delay time of the subsequent gate in at least two gates.

[0030] The target confluence location refers to the pre-defined spatial point where two or more fluid waves superimpose and converge, typically located on a horizontal section before reaching the slope. Based on the characteristic wave velocities obtained from pre-tests, the control system calculates the propagation times required for the first fluid wave generated by opening the gate first and the second fluid wave generated by opening the subsequent gate to reach the target confluence location, and uses the time difference between the two as the opening delay time of the subsequent gate. This time compensation mechanism based on the principle of relative motion ensures that fluid waves released at different times can achieve synchronous and precise superposition at the predetermined spatial location.

[0031] Step S4: Control each gate to open according to the preset opening sequence and opening delay time to generate composite waves at the target composite position.

[0032] Based on the calculated delay time, the control system automatically triggers the actuators of the leading wave gate and the main wave crest gate. For example, the leading wave gate is instantaneously raised to generate a leading wave, and after a precisely calculated delay time, the main wave crest gate is instantaneously raised to generate the main wave crest. The two waves propagate in the fluid channel and meet at the target composite position, forming a composite wave with specific dynamic characteristics. This process is entirely controlled by programmed timing, ensuring the repeatability of the experiment and the stability of waveform generation.

[0033] As a preferred implementation, for the simulation of co-current pursuit composite waves, the above steps can be further refined as follows: In step S1, at least three independent water storage areas are arranged sequentially along the extension direction of the fluid channel: a first water storage area, a second water storage area, and a third water storage area. The first water storage area is located at the upstream end and is used to store the high-potential-energy water that generates the main wave peak; the second water storage area is located in the middle and serves as a transition section to regulate the water flow; the third water storage area includes the target slope and is the main observation area for wave evolution and impact. This three-section layout provides sufficient acceleration space and evolution distance for unidirectional pursuit.

[0034] In step S4, the gates are opened according to a preset opening sequence and opening delay time, including: first opening the leading wave gate near the third reservoir area to generate a leading wave, and then opening the main wave peak gate near the first reservoir area to generate a main wave peak, so that the main wave peak meets and superimposes with the leading wave at the target composite position. Specifically, after the leading wave gate is opened, the water in the intermediate transition zone is released downstream to form a leading wave; subsequently, the main wave peak gate is opened, and the high-energy water in the upstream main reservoir area is released to form the main wave peak. Since the wave velocity of the main wave peak is usually greater than that of the leading wave, and the release time is delayed, it can catch up with and superimpose on the leading wave at the target position, effectively simulating the energy accumulation effect generated by multiple waves of continuous impact in a real tsunami.

[0035] In step S2, the characteristic wave velocity of the fluid wave in each water storage area is calibrated through pre-run testing. This includes: while keeping the initial water level boundaries of each water storage area unchanged, opening the gate of the area to be calibrated individually to release the initial surge wave; recording the opening signal time of the gate in the area to be calibrated, and the arrival time of the wavefront of the initial surge wave at the preset monitoring section; and calculating the characteristic wave velocity based on the spatial distance between the preset monitoring section and the gate in the area to be calibrated, and the time difference between the arrival time and the opening signal time. For example, when calibrating the leading wave velocity, only the leading wave gate is opened, and the wavefront arrival signal is captured using a CBG wave height meter 4 or a Ludong wave height meter 5. This experimental calibration method fully considers the influence of non-ideal factors such as tank wall friction and gate opening speed on the wave velocity, making it more practical for engineering applications than theoretical calculations.

[0036] Furthermore, the preset monitoring sections include a first monitoring section located at the gate of the area to be calibrated, and a second monitoring section located at the target composite position; wherein, the first monitoring section is used to calibrate the characteristic wave velocity of the main wave peak; the characteristic wave velocity is calculated, including: calculating the characteristic wave velocity of the initial surge wave based on the following formula. :

[0037] in, This indicates the spatial distance between the gate in the area to be calibrated and the second monitoring section. This indicates the arrival time of the initial surge wave's wavefront at the second monitoring section. This represents the opening signal time of the gate to be calibrated. This formula establishes a direct mapping relationship between wave velocity and measured spatiotemporal parameters. In practical operation, The trigger signal is taken from the gate drive circuit. The data is taken from the moment of sudden water level jump on the wave height meter; both have millisecond-level accuracy, thus ensuring... This improves the accuracy of the calculations. A similar method can be used to segmentally calibrate the characteristic wave velocities of the main wave peak in different regions, establishing a complete wave velocity database.

[0038] In step S3, based on the target composite position and characteristic wave velocity, the opening delay time of the subsequent gate among at least two gates is determined, including: calculating the first propagation time of the first fluid wave generated by the first gate (which opens before the subsequent gate) to the target composite position; calculating the second propagation time of the second fluid wave generated by the subsequent gate to the target composite position; and determining the difference between the first and second propagation times as the opening delay time of the subsequent gate; wherein the first propagation time is greater than the second propagation time. This logic reflects the timing matching principle of fast waves arriving later and slow waves arriving earlier. Since the main wave peak, i.e., the second fluid wave, has a high speed but a long path or needs to wait for the leading wave to be in place, by accurately calculating the time difference, the arrival times of the two waves at the target point tend to be consistent, avoiding superposition misalignment or separation caused by wave velocity differences.

[0039] To comprehensively capture the dynamic characteristics of complex waves, this method also includes: deploying a water level monitoring array, a flow velocity monitoring array, and a global visual observation system on the fluid channel and the target slope within the fluid channel; real-time acquisition of the instantaneous wave height and local flow velocity of the complex waves through the water level and flow velocity monitoring arrays, and recording the macroscopic physical evolution process of the complex waves through the global visual observation system. Specifically, the water level monitoring array includes an ultrasonic wave height meter 2, a point flow velocity meter (Xiaoweilong II flow velocity meter) 3, a CBG wave height meter 4, a Ludong wave height meter 5, and a profile flow velocity meter 6. The global visual observation system includes a camera 1 mounted above the side of the flume. This multi-dimensional monitoring system can not only verify the accuracy of waveform generation but also reveal the fine flow field structure during wave breaking, climbing, and backflow.

[0040] Furthermore, the method includes: closing all gates after the composite wave reaches the boundary of the fluid channel to prevent interference from reflected waves; and collecting erosion depth and topographic evolution profile data of the target slope after the water in the fluid channel has settled. In the experiment, when the composite surge wave was observed to hit the target slope and return to the right boundary of the flue, the gates were closed in time. This effectively prevented the reflected waves from impacting the slope again, ensuring that the measured topographic evolution data only reflected the effect of the first impact, avoiding data contamination, and improving the purity and reliability of the experimental results.

[0041] As another parallel implementation method, for simulating N-shaped waves with leading receding water characteristics, the above steps can be adjusted as follows: In step S1, different initial water levels are configured for each reservoir area, including: injecting water into the first reservoir area to the first initial water level H1, injecting water into the second reservoir area to the second initial water level H2, and injecting water into the third reservoir area to the third initial water level h0; wherein the first initial water level is greater than the third initial water level, and the third initial water level is greater than the second initial water level, i.e., H1>h0>H2, to generate an N-shaped wave with leading receding water characteristics in the fluid channel. Under this configuration, when the leading wave gate near the third reservoir area opens, because the water level in the third reservoir area is higher than that in the second reservoir area, water flows back towards the middle, forming a receding water wave with a drop in water level downstream; subsequently, the main wave peak gate near the first reservoir area opens, and the high-level water upstream is released to form the main wave peak. This mechanism reproduces the macroscopic physical process of the rapid retreat and violent impact of seawater before a tsunami disaster from a fluid dynamics perspective, filling the technical gap that traditional unidirectional dam failure cannot simulate leading receding water.

[0042] Accordingly, in step S3, when the composite wave has leading receding water characteristics, that is, an N-shaped waveform with a drop in water level followed by a rise in wave crest, and the target composite position is located in the intermediate transition region, the delay time is activated. Calculated based on the following formula:

[0043] in, Indicates the length of the intermediate transition region. This indicates the distance the second fluid wave travels within the intermediate transition region. This represents the characteristic wave velocity of the first fluid wave within the intermediate transition region. This represents the characteristic wave velocity of the second fluid wave within the intermediate transition region. This formula is specifically developed for the mixed phase-to-phase / phase-to-phase motion mechanism of N-shaped waves. The first term in the formula... The second term represents the time required for the receding wave to propagate from the leading wave gate to the recombination point. This represents the time required for the main wave crest to propagate from the main wave crest gate to the rendezvous point. The difference between the two is the delay time required to ensure precise alignment of the receding wave trough and the main wave crest at the predetermined location. It is important to note that here... and Similarly, the results must be obtained through the aforementioned pre-run test calibration to ensure calculation accuracy.

[0044] The composite waves generated using the above method have demonstrated significant technical advantages, as verified by data. For example... Figures 5 to 8As shown, compared with the isolated waves generated by traditional wave generators, the dam-break surge wave generated in this embodiment can maintain a significant long-duration high-water-level plateau period after contacting the target slope and generating the initial flood peak. This realistically reproduces the extreme physical characteristics of a tsunami carrying a massive body of water and continuously rising and submerging the shoreline. Especially under the N-shaped wave condition, the waveform clearly shows the characteristics of a sudden drop in water level followed by a rapid rise, intuitively reproducing the phenomenon of seawater retreat before a tsunami disaster. These characteristics demonstrate the superiority of the method in this application in simulating complex transient hydrodynamic processes, providing a more realistic physical experimental means for coastal engineering disaster prevention and mitigation research.

[0045] Example 2 like Figure 2 and Figure 3 As shown, this embodiment provides a composite tsunami surge simulation system based on dam-break flow. This system, through deep coupling of hardware entities and control logic, provides a reliable physical execution platform for the simulation method described in Embodiment 1. Specifically, the system includes a fluid channel, a gate, a monitoring array, and a control module.

[0046] The fluid channel serves as the main container for the experiment, and its interior contains a target slope. In this embodiment, the fluid channel is constructed using a transparent glass tank to facilitate global visual observation. The target slope, located at the downstream end of the fluid channel, employs a replaceable sandy slope structure to simulate the response of natural coastlines or artificial slopes during terrain evolution. It should be understood that although specific slopes and materials are shown in the figure, in other embodiments, the target slope can be adjusted to a rigid slope, a vegetated slope, or a composite terrain, as long as it provides the physical boundaries for wave rise and erosion.

[0047] like Figure 3 As shown, in the embodiment where two gates are installed in the fluid channel, the fluid channel is divided into three independent water storage areas. Specifically, the main wave crest gate and the leading wave gate are arranged sequentially along the water flow direction, dividing the fluid channel into a first water storage area, a second water storage area, and a third water storage area. This multi-stage gate physical layout is the hardware foundation for achieving differentiated water level storage and graded release. Each gate is equipped with a high-precision servo drive mechanism, capable of achieving millisecond-level instantaneous lifting actions, thereby ensuring that the initial conditions for the generation of dam-break water flow meet the theoretical preset. It should be noted that by adjusting the installation position or number of gates, the length ratio of each water storage area can be flexibly changed to adapt to the wave simulation requirements of different wavelengths or periods.

[0048] The monitoring array is deployed along the fluid channel and the target slope. To comprehensively capture the dynamic characteristics of complex waves, the array employs a spatial combination of multiple sensor types. For example, an ultrasonic wave height meter is positioned at the toe of the target slope to acquire instantaneous water surface elevation in the wave-breaking zone at high frequency; multiple CBG wave height meters and Ludong wave height meters are deployed along the straight sections and transition zones of the fluid channel to record waveform evolution and attenuation characteristics during wave propagation; point velocity meters and profile velocity meters are also installed at key sections to acquire point velocity and vertical velocity distribution profiles near the seabed, respectively. Furthermore, the system includes cameras as a global visual observation tool, mounted above and to the side of the fluid channel to record the macroscopic flow field morphology. This multi-dimensional monitoring array design ensures that the system can simultaneously acquire wave height, velocity, and image data, providing comprehensive data support for subsequent verification of waveform generation accuracy and analysis of water-sediment interaction mechanisms.

[0049] The control module is communicatively connected to the gate and the monitoring array. It is configured to execute a composite tsunami surge simulation method based on dam-break flow, as described in Example 1. The control module is not a general-purpose computer device, but rather an automated control center integrating a dedicated instruction set and functional units. Specifically, the control module is internally configured to include a wave velocity calibration unit, a delay calculation unit, and a timing triggering unit. The wave velocity calibration unit receives water level jump signals collected by the monitoring array during pre-operation testing and automatically calculates the characteristic wave velocities of each area in conjunction with the gate opening signal. The delay calculation unit calculates the subsequent gate opening delay time in real time based on the calibrated wave velocity parameters and the target composite position. The timing triggering unit sends precise synchronous trigger pulses to the gate drive mechanism based on the calculation results. Through this modular configuration of functional units, the control module transforms the abstract simulation method into deterministic hardware execution actions, eliminating timing errors caused by manual operation and ensuring microsecond-level accuracy in the superposition of composite waves at predetermined spatial positions. It should be noted that although the system provided in this embodiment primarily simulates tsunami waves and slope sediment erosion, its hardware architecture and control logic have broad applicability. The system is also suitable for physical model experiments of various complex waves or transient water flows, such as storm surge, dam-break flood evolution, and estuarine saltwater wedge intrusion. By adjusting the initial water level configuration and control parameters, researchers can reproduce various extreme hydrodynamic processes on the same hardware platform, significantly improving the utilization rate of experimental equipment and the efficiency of scientific research output.

[0050] Example 3 This embodiment provides a method for simulating tsunami waves and slope erosion using single-dam-break water flow, specifically including the following detailed implementation steps: S1: Construct a real coastal physical experiment model.

[0051] like Figure 2As shown, an experimental environment was constructed in a large transparent glass tank, 40m long, 1.5m wide, and 2.0m high. At the downstream end of the tank, i.e., at the end of the wave propagation direction, a sandy slope with a length of 8m, a height of 0.8m, a slope of 1:10, and a median grain size of 0.36mm was set up to simulate a natural coastal beach or artificial shoreline.

[0052] S2: Layout of transient hydrodynamic and flow field monitoring system.

[0053] To accurately capture the transient hydrodynamic characteristics of the dam-break flow and its local flow field disturbances during impact with the slope, coordinated data monitoring instruments were deployed along the experimental flume and around the slope, specifically including: Wave height meters: CBG wave height meters are deployed at locations 2m and 4m away from the toe of the slope, ultrasonic wave height meters are deployed at the toe of the slope, and Ludong wave height meters are deployed at locations 6m, 10.3m and 13.3m away from the toe of the slope to monitor the wave height and morphology of the dam break water flow in real time, providing data support for subsequent waveform comparison.

[0054] Flow meter: The Xiaoweilong second-generation flow meter was placed at the toe of the slope, and the profile flow meter was placed 4m away from the toe of the slope. Real-time instantaneous flow velocity parameters of the dam-break water flow during the breaking, climbing, and backflow stages on the slope surface were collected.

[0055] Camera: A high-definition camera was installed at a position 39.5m from the end of the experimental water tank along its horizontal central axis and 2m vertically from the bottom of the tank. This camera could obtain a global field of view and record the entire physical process from the release of the dam-break flood peak, its rapid ascent along the sandy slope, to its final return flow away from the shore.

[0056] S3: Initialization settings for the dam break wave generation system.

[0057] At the upstream end of the tidal flume, the end without a ramp, a momentary lifting gate is installed as a dam-break initiation device, 17.6m from the flume boundary, dividing the flume into an upstream reservoir area and a downstream propagation zone. Water is injected into the reservoir area to a predetermined first impoundment level W1, and still water is injected into the second impoundment area to a depth W2. The magnitudes of W1 and W2 are adjusted according to a calculation formula based on different Froude numbers to simulate the initial arrival waves of tsunamis of varying intensities.

[0058] S4: Generate transient tsunami surge and perform impact experiment.

[0059] The dam gates were opened instantly, releasing water from the upstream reservoir area. This caused the water's potential energy to be converted into kinetic energy instantly, forming a dam-break flood peak with nonlinear characteristics. As the surge wave propagated towards the shore, it encountered a 1:10 sandy slope and underwent severe shallow-water deformation, forming a steep wavefront that simulated the wall of water formation during a tsunami approaching the shore. Subsequently, the water flow broke up and climbed on the sandy slope.

[0060] S5: Verification and data collection of the scouring evolution process.

[0061] After the water flow in the trough has completely stopped and the erosion of the terrain has stabilized, the erosion depth at each key observation point on the sandy slope is measured to obtain the final terrain evolution characteristics.

[0062] S6: Comparison of hydrodynamic data and verification of effects.

[0063] The wave height meter arranged as described above is used to collect water surface elevation data in real time at high frequency. For example... Figure 4 As shown, the most significant difference between the method of this invention and traditional wave generation methods lies in their hydrodynamic characteristics. Comparing transient wave height and duration, the wave height data of traditional isolated waves, when evolving along a slope, exhibits an extremely short, steep, single-peak shape. After the peak, the water level quickly drops back to the still water level, indicating that the energy carried by the wave in a single event is limited. However, the dam-break surge wave simulated in this embodiment, after generating an extremely high initial peak upon contact with the slope toe and subsequent breakup, does not immediately drop in wave height but rather remains on a water depth platform for a relatively long period.

[0064] In summary, the physical experimental data of this invention verify the scientific validity and superiority of using a single dam-break flow to simulate a real tsunami wave and its erosion and damage mechanism on sandy bank slopes. The single dam-break method for simulating tsunami waves can realistically reproduce the waveform characteristics of a continuously advancing tsunami, eliminating pulse distortion. It overcomes the limitation of traditional continuous isolated waves that rely on multiple superpositions to simulate tsunamis. Regardless of the absolute wave height, traditional isolated waves exhibit transient pulses that rapidly and symmetrically recede along the slope; while the single dam-break flow of this invention, after impacting the sandy slope and generating the initial flood peak, can maintain a significant, long-duration high-water-level plateau period, morphologically realistically reproducing the extreme physical characteristics of a tsunami carrying a massive body of water continuously rising and submerging along the bank slope.

[0065] Example 4 Although a single dam breach addresses the short duration of isolated waves, it is essentially still a single positive surge wave and cannot effectively reproduce the development process of a real tsunami disaster. This embodiment adds a gate to the single dam breach simulation wave generation method, enabling the simulation of different tsunami waveforms under more diverse conditions. The specific experimental steps are as follows: S1: Experimental system construction.

[0066] like Figure 3As shown, an experimental environment was constructed in a transparent glass tank measuring 40m long, 1.5m wide, and 2m high. At one end of the tank, a sandy slope with a gradient of 1:10, a length of 8m, a height of 0.8m, and a median particle size of 0.36mm was set up to simulate a natural coastal beach or artificial shoreline.

[0067] S2: Layout of transient hydrodynamic and flow field monitoring system.

[0068] To accurately capture the transient hydrodynamic characteristics of the dam-break flow and its local flow field disturbances during impact with the slope, coordinated data monitoring instruments were deployed along the experimental flume and around the slope, specifically including: Wave height meters: CBG wave height meters are deployed at locations 2m and 4m away from the toe of the slope, ultrasonic wave height meters are deployed at the toe of the slope, and Ludong wave height meters are deployed at locations 6m, 10.3m and 13.3m away from the toe of the slope to monitor the wave height and morphology of the dam break water flow in real time, providing data support for subsequent waveform comparison.

[0069] Flow meter: The Xiaoweilong second-generation flow meter was placed at the toe of the slope, and the profile flow meter was placed 4m away from the toe of the slope. Real-time instantaneous flow velocity parameters of the dam-break water flow during the breaking, climbing, and backflow stages on the slope surface were collected.

[0070] Camera: A high-definition camera is installed at a position 39.5m from the end of the experimental water tank along its horizontal central axis and 2m vertically from the bottom of the tank. This camera, due to its specific spatial placement, provides a global field of view and can completely record the entire simulation experiment.

[0071] S3: Initialization settings for the double-gate dam break wave generation system.

[0072] Two gates were installed at the upstream end of the flume, dividing it into three independent zones: the upstream main reservoir zone, the intermediate transition zone, and the downstream propagation zone. The downstream propagation zone included the experimental area with a sandy slope. Different Froude numbers were determined in the shallow and deep water zones according to the formula for calculating surge intensity. The hydrodynamics were dynamically adjusted to induce a low-Froude-number wave to spontaneously evolve into a breaking surge with an extremely high Froude number midway through its course.

[0073] S4: Simulates the generation of tsunami waves.

[0074] Wave generation is achieved through dual-gate timing control, and the opening delay time of the two gates is calculated using fluid dynamics theory. First, the location for generating the composite surge wave is determined, with the distance from the left gate being... Distance from the intermediate transition zone The time it takes for the frontguide wave to travel when the frontguide gate is opened is . The main wave peak motion time is + The delay time can then be calculated as follows: The characteristic wave velocities c1, c2, and c3 were calculated based on the preliminary experimental results. The preliminary experimental segmented tracking and system calibration process for the characteristic wave velocities is as follows: To obtain the nonlinear characteristic wave velocities c1, c2, and c3 under real varying water depth and moving boundary flow fields, and to support the accurate solution of the same-direction pursuit equation, this system underwent preliminary experimental calibration before the formal composite experiment. The specific calibration procedure is as follows: (1) Steps for unifying the monitoring array layout and time reference. For example... Figure 3 As shown, a high-frequency water level monitoring array was arranged along the experimental flume. The position of the right gate was set as the starting point X0 of the spatial monitoring section; the first monitoring section X1 was arranged at the left gate, i.e., at a distance Lm from the starting point; and the second monitoring section X2 was arranged at the predetermined wave crest composite point on the sandy slope, i.e., at a distance Ls from the left gate. Simultaneously, the instantaneous opening electrical signals of the left and right gates were connected to the control system as the absolute time zero point of the wavefront evolution. This control system mainly consists of a signal acquisition (CBG wave height meter) computer host and software calculation.

[0075] (2) Calculate the initial surge wave characteristic velocity c1. Set the initial static water level boundary in the water tank consistent with the formal experiment, that is, keep the initial water level of the first water storage area as H1, the initial water level of the second water storage area as H2, and the initial water level of the third water storage area as h0.

[0076] Keep the right gate closed and open the left gate instantaneously. The control system records the start signal time TA0 of the left gate opening; subsequently, the wave height meter located at the second monitoring section X2 captures the water level jump caused by the arrival of the initial surge wave front and records the arrival time TA1.

[0077] Based on the spatial distance and the measured time history difference, the system automatically calculates the initial surge characteristic velocity c1:

[0078] (3) Calculate the dynamic tracking characteristic wave velocity c2 and the coupling characteristic wave velocity c3 of the main wave peak. Restore the initial water level, that is, keep the initial water level of the first water storage area as H1, the initial water level of the second water storage area as H2, and the initial water level of the third water storage area as h0. Perform multi-gradient trial operation calibration of the characteristic velocity of the main wave peak under different tracking intervals, including interference of the front and rear surge waves. First, the main control unit opens the left gate to release the initial surge wave; then, set a series of gradient change test delay times, such as delaying by 1s, 1.5s, 2s... in sequence, and control the right gate to open to release the main wave peak.

[0079] In each test set, the host records absolute time points: the right gate opening signal time TB0; the time when the main wave peak crosses the first monitoring section X1 TB1; and the time when the main wave peak crosses the second monitoring section X2 TB2. The system calculates the characteristic wave velocity combinations of the main wave peak segment by segment and establishes a wave velocity database associated with the test delay time. The dynamic tracking characteristic wave velocity of the main wave peak in the intermediate transition zone is calculated using the following formula:

[0080] The coupling characteristic wave velocity of the main wave peak in the downstream experimental area is calculated using the following formula:

[0081] (4) Mapping database establishment and closed-loop calling steps. The control system binds the characteristic wave velocity parameter set obtained from the above calibration with the corresponding initial water level and stores it in the preset characteristic parameter mapping database. When performing the formal double-peak composite automated experiment, the system directly retrieves and extracts the empirical wave velocity value corresponding to the current working condition, substitutes it into the same-direction pursuit delay control equation, thereby completely eliminating analytical calculation errors and realizing the microsecond-level precise composite of double-peak superimposed tsunami waves at the predetermined spatial position.

[0082] The simulation experiment began with the leading wave gate near the slope being opened. Because the water level in the middle zone was higher than that in the slope zone, water from the middle zone was released towards the slope, forming the first upward-rising initial surge wave on the slope surface. Subsequently, the gate opening delay time was calculated based on the composite point, and the main wave peak gate on the right was opened accordingly. Water from the upstream main reservoir was released, forming a main dam-break flood peak carrying enormous kinetic energy. The main wave peak chased the initial surge wave, causing a secondary, superimposed, extreme onshore impact and damage to the sandy slope. In this experiment, after observing the composite surge wave formed after both gates were fully opened rushing up the slope and returning to the right boundary of the channel, both gates were closed to prevent the wave backflow and impact on the slope, thus avoiding data interference.

[0083] When setting up a dual-gate system, the potential energy difference is used to generate the waveform characteristics of a real tsunami wave, with a high water level on both sides and a low water level in the middle, creating a wave trough followed by a peak. The delayed gate opening time for the N-shaped wave is calculated based on the peak superposition delay time. Specifically: Assume the length of the transition zone between the two gates is To ensure the receding wave and the main wave crest meet at a predetermined location, the propagation times of both need to be determined. After the left gate opens, the characteristic wave velocity of the receding wave in the intermediate transition zone is c1. Assuming the main wave crest travels a distance of x, the receding wave travels a distance of Lm-x, and the time to reach the rendezvous point is... The tracking characteristic wave velocity of the main wave peak in the intermediate transition region is c2, its travel distance is x, and the required time is... Therefore, the formula for calculating the delay time can be derived as follows: c1 and c2 were also obtained through preliminary experiments, that is, by opening the left and right gates separately to calculate the time it takes for the receding wave and the main wave crest to pass through the two CBG wave height meters, and then the data was transmitted back to the computer and the software was used to calculate the formula to obtain the characteristic wave velocity.

[0084] The simulation experiment begins by restoring the initial water levels of each reservoir area, ensuring that the initial water level in the third reservoir area is lower than that in the first reservoir area but higher than that in the second reservoir area. The left gate is opened. Because the initial water level in the third reservoir area is higher than that in the second, water from the third reservoir area instantly flows back into the second reservoir area, causing a strong drop in water level and offshore bottom current on the sandy slope and its leading edge. This stage realistically simulates the leading wave trough phenomenon of rapid tidal retraction before a tsunami disaster, leading to initial seaward suspension and loss of sediment on the slope and at the bottom of the slope. Subsequently, based on the location of the composite point, the delay time formula is applied, and the right gate is opened according to the obtained delay time. Water from the first reservoir area is released, forming a dam-break flood peak with nonlinear characteristics. The N-type surge wave, characterized by a trough followed by a crest, becomes steeper at the wavefront as it propagates towards the shore, then violently breaks up and rapidly ascends on the 1:10 sandy slope, and after reaching its maximum height, it forms a strong offshore backflow due to gravity. This process fully reproduces the hydrodynamic mechanism of a real tsunami, which involves receding tide followed by rising tide, and the entire process of its impact on natural bank slopes.

[0085] S5: Acquisition of slope topographic evolution. After the water flow in the flume has completely stopped, readings are taken on the sandy slope to obtain the final erosion depth and overall profile evolution of the sandy slope surface.

[0086] S6: Hydrodynamic Data Comparison and Effect Verification. This embodiment derives a method for dynamically adjusting the composite point position and accurately calculating the composite time for simulating N-shaped tsunami waves. Initially, a long-duration, deep-amplitude sudden drop in water level was induced on the slope surface, visually reproducing the macroscopic physical phenomenon of the rapid retreat of seawater before a tsunami disaster from a hydrodynamic perspective. Secondly, this embodiment adds a gate to the single dam breach, thereby simulating unbroken wave-like swells in deep water areas and, simultaneously, simulating highly destructive breaking swells as they rush towards the shallow shore, effectively restoring the abrupt changes in morphology and intensity of tsunami waves caused by shallow water deformation. Furthermore, by adjusting parameters, the composite swell point position can be adjusted, thus simulating various types of tsunami composite swells.

[0087] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for simulating composite tsunami surge waves based on dam-break flow, characterized in that, Includes the following steps: At least two gates are set in the fluid channel to divide the fluid channel into at least three independent water storage areas, and different initial water levels are configured for each water storage area to form a dam-break water flow sequence with preset waveform characteristics; The characteristic wave velocity of the fluid wave in each of the aforementioned water storage areas was calibrated through pre-run tests. Based on the target composite position and the characteristic wave velocity, determine the opening delay time of the subsequent gate among the at least two gates; The gates are opened according to a preset opening sequence and an opening delay time to generate composite waves at the target composite position.

2. The method for simulating composite tsunami surge waves based on dam-break flow according to claim 1, characterized in that, The at least three independent water storage areas include a first water storage area, a second water storage area, and a third water storage area arranged sequentially along the extension direction of the fluid channel; The step of controlling the opening of each gate according to the preset opening sequence and the opening delay time includes: first opening the gate near the third water storage area to generate a leading wave, and then opening the gate near the first water storage area to generate a main wave peak, so that the main wave peak meets and superimposes with the leading wave at the target composite position.

3. The method for simulating composite tsunami surge waves based on dam-break flow according to claim 2, characterized in that, The initial water levels for each of the aforementioned water storage areas are not entirely the same, including: Water is injected into the first water storage area to the first initial water level, water is injected into the second water storage area to the second initial water level, and water is injected into the third water storage area to the third initial water level; Wherein, the first initial water level is greater than the third initial water level, and the third initial water level is greater than the second initial water level, so as to generate an N-shaped wave with leading receding water characteristics in the fluid channel.

4. The method for simulating composite tsunami surge waves based on dam-break flow according to claim 1, characterized in that, The characteristic wave velocity of the fluid wave in each of the aforementioned water storage areas was calibrated through pre-run tests, including: While keeping the initial water level boundaries of each of the aforementioned water storage areas unchanged, the gates of the areas to be calibrated are opened individually to release the initial surge wave; Record the opening signal time of the gate in the area to be calibrated, and the arrival time of the wavefront of the initial surge to the preset monitoring section. The characteristic wave velocity is calculated based on the spatial distance between the preset monitoring section and the gate of the area to be calibrated, and the time difference between the arrival time and the opening signal time.

5. The method for simulating composite tsunami surge waves based on dam-break flow according to claim 4, characterized in that, The preset monitoring section includes a first monitoring section located at the gate of the area to be calibrated, and a second monitoring section located at the target composite position; wherein, the first monitoring section is used to calibrate the characteristic wave velocity of the main wave peak; The calculation of the characteristic wave velocity includes: The characteristic wave velocity of the initial surge wave is calculated based on the following formula. : in, This indicates the spatial distance between the gate in the area to be calibrated and the second monitoring section. This indicates the arrival time of the initial surge wave's wavefront at the second monitoring section. This indicates the opening signal time of the gate to be calibrated.

6. The method for simulating composite tsunami surge waves based on dam-break flow according to claim 4, characterized in that, Based on the target composite location and the characteristic wave velocity, the opening delay time of the subsequent gate among the at least two gates is determined, including: Calculate the first propagation time of the first fluid wave generated by the first gate that opens before the subsequent gate, which of the at least two gates, to the target composite position; Calculate the second propagation time of the second fluid wave generated by the subsequent gate to the target composite position; The difference between the first propagation time and the second propagation time is determined as the opening delay time of the subsequent gate; wherein the first propagation time is greater than the second propagation time.

7. A method for simulating composite tsunami surge waves based on dam-break flow according to claim 6, characterized in that, The water storage area between the first opened gate and the subsequent gate in the at least three independent water storage areas is an intermediate transition area. When the composite wave has leading receding water characteristics, that is, an N-shaped waveform with a drop in water level followed by a rise in wave crest, and the target composite position is located within the intermediate transition area, the opening delay time... Calculated using the following formula: in, Indicates the length of the intermediate transition region. This indicates the distance the second fluid wave travels within the intermediate transition region. This represents the characteristic wave velocity of the first fluid wave within the intermediate transition region. This indicates the characteristic wave velocity of the second fluid wave within the intermediate transition region.

8. The method for simulating composite tsunami surge waves based on dam-break flow according to claim 1, characterized in that, The method further includes: A water level monitoring array, a flow velocity monitoring array, and a global visual observation system are arranged in the fluid channel and on the target slope within the fluid channel. The instantaneous wave height and local flow velocity of the composite wave are collected in real time by the water level monitoring array and the flow velocity monitoring array, and the macroscopic physical evolution process of the composite wave is recorded by the global visual observation system.

9. A method for simulating composite tsunami surge waves based on dam-break flow according to claim 8, characterized in that, The method further includes: After the composite wave reaches the boundary of the fluid channel, each of the gates is closed to prevent interference from reflected waves; After the water in the fluid channel has settled, erosion depth and topographic evolution profile data of the target slope are collected.

10. A composite tsunami surge simulation system based on dam-break flow, characterized in that, include: A fluid channel, wherein a target slope is provided within the fluid channel; At least two gates are provided in the fluid channel to divide the fluid channel into at least three independent water storage areas; A monitoring array is arranged in the fluid channel and the target slope. A control module, communicatively connected to the at least two gates and the monitoring array, is configured to perform a composite tsunami surge simulation method based on dam-break flow as described in any one of claims 1 to 9.

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