A method and device for simulating a slamming wave based on time difference regulation

Abstract

The present application relates to the technical field of slamming wave simulation, and specifically discloses a slamming wave simulation method and device based on time difference regulation. The method first determines multiple groups of target regular waves with specific periods and amplitudes, measures the time difference of wave peaks from wave generation to a specified action point for each group of regular waves; then constructs a wave generation formula based on the time difference, directly generates a composite wave in a large wave tank through the wave generation formula, and simultaneously adopts a slow start and slow stop control to avoid wave start / stop distortion, thereby ensuring that the wave peaks of each group of regular waves in the composite wave are superimposed synchronously at the specified action point to form superimposed waves with a slamming effect. The present application is suitable for wave resistance performance testing of large marine engineering structures, and has high simulation accuracy, simple operation and strong repeatability.

Description

Technical Field

[0001] This invention relates to the field of slamming wave simulation technology, and in particular to a slamming wave simulation method and apparatus based on time difference control. Background Technology

[0002] In large-scale marine engineering, wave slamming is a core factor affecting structural safety. Slamming waves are often formed by the simultaneous superposition of multiple waves of different periods on the structure's surface, and their impact force is far greater than that of a single wave. Existing simulation methods suffer from problems such as insufficient tank size, poor wave parameter matching, failure to consider waveform stability during long-distance propagation, and insufficient fine-grained control over the wave's "start-stabilize-stop" phase, making it difficult to accurately simulate the slamming effect in the actual marine environment. Therefore, it is necessary to develop a more realistic simulation method that combines large tanks with waves of specific parameters.

[0003] To address this, a method and apparatus for simulating slamming waves based on time difference regulation is proposed. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a time-difference-based slamming wave simulation method, suitable for testing the stress performance of large structures (such as deep-sea platforms and ultra-long breakwaters) under extreme wave slamming, comprising the following steps:

[0005] S10. Select the target location of the simulated wave impacting the building as the designated point of action; at the designated point of action, select multiple sets of regular waves with different periods as the simulation objects; wherein, each set of regular waves includes a preset number of waves;

[0006] S20. Perform wave generation test on each group of regular waves separately, and record the time from the start of wave generation to the first time the wave crest in the group of regular waves reaches the designated point of action, which is recorded as the wave crest propagation time;

[0007] S30. Using the crest propagation time of one set of regular waves as a reference, calculate the crest propagation time difference between the other sets of regular waves and the reference set of regular waves;

[0008] S40. Determine the corrected start time of each group of regular waves based on the wave crest propagation time difference; according to the corrected start time, combined with the slow start coefficient and slow stop coefficient, obtain the corrected displacement expression of each group of regular waves; based on the corrected displacement expression, construct the instantaneous displacement formula of the composite wave.

[0009] S50. Take the derivative of the instantaneous displacement formula of the composite wave twice to obtain the velocity curve and acceleration curve. If both the velocity curve and acceleration curve are continuous, the wave generation process is judged to be smooth and without abrupt changes.

[0010] Each set of regular waves contains 10-50 waves, and the number of waves in each set is the same.

[0011] The corrected displacement expressions include: instantaneous displacement formulas for the start-up phase, the steady-state phase, and the stopping phase;

[0012] The instantaneous displacement formula for the gradual start-up phase is:

[0013] ;

[0014] In the formula, Let be the instantaneous displacement of the i-th group of regular waves at time t; Let be the period of the i-th wave group; The corrected start time of the i-th wave group is determined based on the time difference between the crest propagation of the regular wave and the reference group regular wave. The corrected start time of the reference group regular wave is 0. The easing coefficient corresponds to time t;

[0015] The amplitude reaches its maximum and then remains stable for a period of time. During the stable phase, the instantaneous displacement formula for the stable phase is:

[0016] ;

[0017] The instantaneous displacement formula for the easing phase is:

[0018] ;

[0019] In the formula, Let be the easing coefficient corresponding to time t.

[0020] The expression for the easing coefficient is:

[0021] ;

[0022] in, The midpoint of the easing time; =0.005, which is the start-up rate coefficient.

[0023] The expression for the easing factor is:

[0024] ;

[0025] in, =0.001 is the stopping rate coefficient. This is the reference time at the end of the stable phase.

[0026] The total instantaneous displacement of the composite wave during the gradual onset phase is the sum of the instantaneous displacements of each set of regular waves during the gradual onset phase, that is:

[0027] ;

[0028] in, Let i be the period of the i-th wave group. The corrected start time for the i-th wave group is based on the wave crest propagation time difference Δt. i Set the baseline group to 0, and the other groups to 0. =Δt i ;

[0029] Stable phase: The total instantaneous displacement of the composite wave is the sum of the instantaneous displacements of each set of regular waves during the stable phase, that is:

[0030] ;

[0031] Among them, the duration of the stable phase Determined by the number and period of waves, the amplitude of each group of waves remains at its maximum during this stage;

[0032] Descent phase: The instantaneous total displacement of the composite wave is the sum of the instantaneous displacements of each group of regular waves during the descent phase, that is:

[0033] ;

[0034] in, The instantaneous total displacement of the synthesized wave.

[0035] The velocity curve is the first derivative of the instantaneous total displacement of the composite wave with respect to time, expressed as:

[0036] ;

[0037] in, The first derivative of the instantaneous total displacement of the composite wave with respect to time is the velocity curve. Let be the first derivative of the instantaneous displacement of the i-th group of regular waves at time t with respect to time;

[0038] The velocity formula for a single wave group in the initial stage is:

[0039] ;

[0040] in, The start-up coefficient The first derivative with respect to time;

[0041] The stable phase is as follows:

[0042] ;

[0043] The easing phase is as follows:

[0044] ;

[0045] ;

[0046] in, Delay coefficient The first derivative with respect to time;

[0047] The acceleration curve is the second derivative of the instantaneous total displacement of the composite wave with respect to time, expressed as:

[0048] ;

[0049] in, This is the second derivative of the instantaneous total displacement of the composite wave with respect to time, i.e., the acceleration curve; Let be the second derivative of the instantaneous displacement of the i-th group of regular waves at time t with respect to time;

[0050] The acceleration formula for a single wave in the initial stage is:

[0051] ;

[0052] in, The start-up coefficient The second derivative with respect to time;

[0053] The stable phase is as follows:

[0054] ;

[0055] The easing phase is as follows:

[0056] ;

[0057] in, Delay coefficient The second derivative with respect to time.

[0058] The standard for continuity verification is that the left and right limit values ​​of the velocity curve are equal at the transition point from the gradual easing to the steady state and at the transition point from the steady state to the gradual stopping. The left and right limit values ​​of the acceleration curve are also equal.

[0059] An apparatus for implementing the method, comprising:

[0060] Wave tanks: used to provide space for wave generation and propagation;

[0061] Wave generating device: Installed at one end of the wave tank, it is used to generate periodic regular waves according to the wave generating formula, and can be operated according to the slow start and slow stop formula and the determined wave amplitude maintenance time.

[0062] Wave crest monitoring module: Installed at a designated point of action, it detects the time when the wave crest reaches that point;

[0063] Control module: Electrically connected to the wave generator and the wave crest monitoring module respectively, used to record the wave crest propagation time of each group of waves, calculate the time difference, adjust the start time of the wave generator and the instantaneous displacement of the waves according to the synthetic wave formula, and control the parameters of the slow start, wave amplitude maintenance and slow stop stages.

[0064] The embodiments of the present invention have the following technical effects:

[0065] Closely aligned with real-world scenarios: The use of a 456m long large water tank and waves with a period of 3.0-6.0s can simulate the superposition of waves after long-distance propagation, which is closer to the deep-sea / offshore engineering environment;

[0066] High simulation accuracy: By controlling the time difference of waves with 13 specific parameters, combined with three-stage control of slow start (rate 0.005), stabilization (400s), and slow stop (rate 0.001), it ensures that multiple wave peaks are synchronously superimposed without distortion, making the simulation of impact effects more accurate.

[0067] Highly scalable: It supports simulating slamming waves of different intensities by adjusting the period, amplitude, and number of waves, meeting the wave resistance testing needs of large marine structures (such as deep-sea platforms and ultra-long breakwaters). Attached Figure Description

[0068] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific 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 from these drawings without creative effort.

[0069] Figure 1 This is a flowchart of a slamming wave simulation method based on time difference control provided in an embodiment of the present invention;

[0070] Figure 2 This is a data logic diagram of a slamming wave simulation method based on time difference control provided in an embodiment of the present invention. Detailed Implementation

[0071] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention are described clearly and completely below. The described embodiments are only some embodiments of this invention, not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are also part of this invention.

[0072] Example 1:

[0073] This invention proposes a slamming wave simulation method based on time difference regulation, the process of which is as follows: Figure 1 As shown, its data logic is as follows: Figure 2 As shown, it specifically includes:

[0074] S10. Select the target location of the simulated wave impacting the building as the designated point of action; at the designated point of action, select multiple sets of regular waves with different periods as the simulation objects; wherein, each set of regular waves includes a preset number of waves.

[0075] Preferably, each group of regular waves contains 10-50 waves, and the number of waves in each group is the same.

[0076] S20. Perform wave generation test on each group of regular waves separately, and record the time from the start of wave generation to the first time the wave crest in that group of regular waves reaches the designated point of action, which is recorded as the wave crest propagation time.

[0077] S30. Using the crest propagation time of one set of regular waves as a reference, calculate the crest propagation time difference between the other sets of regular waves and the reference set of regular waves.

[0078] S40. Determine the corrected start time of each group of regular waves based on the wave crest propagation time difference; according to the corrected start time, combined with the slow start coefficient and slow stop coefficient, obtain the corrected displacement expression of each group of regular waves; based on the corrected displacement expression, construct the instantaneous displacement formula of the synthetic wave.

[0079] The corrected displacement expressions include: instantaneous displacement formulas for the start-up phase, the steady-state phase, and the stopping phase;

[0080] The instantaneous displacement formula for the gradual start-up phase is:

[0081] ;

[0082] In the formula, Let be the instantaneous displacement of the i-th group of regular waves at time t; Let be the period of the i-th wave group; The corrected start time of the i-th wave group is determined based on the time difference between the crest propagation of the regular wave and the reference group regular wave. The corrected start time of the reference group regular wave is 0. The easing coefficient corresponds to time t;

[0083] The amplitude reaches its maximum and then remains stable for a period of time. During the stable phase, the instantaneous displacement formula for the stable phase is:

[0084] ;

[0085] The instantaneous displacement formula for the easing phase is:

[0086] ;

[0087] In the formula, Let be the easing coefficient corresponding to time t.

[0088] The expression for the easing coefficient is:

[0089] ;

[0090] in, The midpoint of the easing time; =0.005, which is the start-up rate coefficient.

[0091] The expression for the easing factor is:

[0092] ;

[0093] in, =0.001 is the stopping rate coefficient. This is the reference time at the end of the stable phase.

[0094] The total instantaneous displacement of the composite wave during the gradual onset phase is the sum of the instantaneous displacements of each set of regular waves during the gradual onset phase, that is:

[0095] ;

[0096] in, Let i be the period of the i-th wave group. The corrected start time for the i-th wave group is based on the wave crest propagation time difference Δt. i Set the baseline group to 0, and the other groups to 0. =Δt i ; The total number of groups of regular waves;

[0097] Stable phase: The total instantaneous displacement of the composite wave is the sum of the instantaneous displacements of each set of regular waves during the stable phase, that is:

[0098] ;

[0099] Among them, the duration of the stable phase Determined by the number and period of waves, the amplitude of each group of waves remains at its maximum during this stage;

[0100] Descent phase: The instantaneous total displacement of the composite wave is the sum of the instantaneous displacements of each group of regular waves during the descent phase, that is:

[0101] ;

[0102] in, The instantaneous total displacement of the synthesized wave.

[0103] This invention significantly improves the quality of simulated waves through a three-stage control method. It effectively avoids waveform distortion caused by sudden start and stop of the wave generator and secondary reflection contamination in the water tank, ensuring that the final synthesized slamming waves are composed of clean, regularly shaped waves superimposed on each other.

[0104] S50. Take the derivative of the instantaneous displacement formula of the composite wave twice to obtain the velocity curve and acceleration curve. If both the velocity curve and acceleration curve are continuous, the wave generation process is judged to be smooth and without abrupt changes.

[0105] The velocity curve is the first derivative of the instantaneous total displacement of the composite wave with respect to time, expressed as:

[0106] ;

[0107] in, The first derivative of the instantaneous total displacement of the composite wave with respect to time is the velocity curve. Let be the first derivative of the instantaneous displacement of the i-th group of regular waves at time t with respect to time.

[0108] The velocity formula for a single wave group in the initial stage is:

[0109] ;

[0110] in, The first derivative of the easing coefficient with respect to time;

[0111] The stable phase is as follows:

[0112] ;

[0113] The easing phase is as follows:

[0114] ;

[0115] ;

[0116] in, This is the first derivative of the easing coefficient with respect to time.

[0117] The acceleration curve is the second derivative of the instantaneous total displacement of the composite wave with respect to time, expressed as:

[0118] ;

[0119] in, This is the second derivative of the instantaneous total displacement of the composite wave with respect to time, i.e., the acceleration curve; Let be the second derivative of the instantaneous displacement of the i-th group of regular waves at time t with respect to time;

[0120] The acceleration formula for a single wave in the initial stage is:

[0121] ;

[0122] in, This is the second derivative of the easing coefficient with respect to time;

[0123] The stable phase is as follows:

[0124] ;

[0125] The easing phase is as follows:

[0126] ;

[0127] in, This is the second derivative of the easing coefficient with respect to time.

[0128] The standard for continuity verification is that the left and right limit values ​​of the velocity curve are equal at the transition point from the gradual easing to the steady state and at the transition point from the steady state to the gradual stopping. The left and right limit values ​​of the acceleration curve are also equal.

[0129] Example 2:

[0130] This invention also proposes a time-difference-based slamming wave simulation device to implement a time-difference-based slamming wave simulation method. The device includes:

[0131] Wave tanks: used to provide space for wave generation and propagation;

[0132] Wave generating device: Installed at one end of the wave tank, it is used to generate periodic regular waves according to the wave generating formula, and can be operated according to the slow start and slow stop formula and the determined wave amplitude maintenance time.

[0133] Wave crest monitoring module: Installed at a designated point of action, it detects the time when the wave crest reaches that point;

[0134] Control module: Electrically connected to the wave generator and the wave crest monitoring module respectively, used to record the wave crest propagation time of each group of waves, calculate the time difference, adjust the start time of the wave generator and the instantaneous displacement of the waves according to the synthetic wave formula, and control the parameters of the slow start, wave amplitude maintenance and slow stop stages.

[0135] Based on the actual implementation process, a specific analysis of a slamming wave simulation method based on time difference control is conducted:

[0136] Step S10: Select the target location of the simulated wave impacting the building as the designated point of action; at the designated point of action, select multiple sets of regular waves with different periods as the simulation objects; wherein, each set of regular waves includes a preset number of waves.

[0137] Set up a large wave tank with dimensions of 456m (length) × 5m (width) × 12m (depth). Set up a designated point of action (simulating the key location of a large building being hit by a bang) 300m away from the wave-generating device inside the tank.

[0138] A wave height sensor (sampling frequency of 200Hz) is installed at this point to accurately capture the arrival time of the wave crest after long-distance propagation.

[0139] Multiple sets of regular wave parameters and wave generation formulas were selected. Thirteen sets of regular waves with different periods were selected, and the parameters of each set are shown in Table 1 (period T). i , amplitude A i , wave height H i =2A i );

[0140] Table 1. Example table of parameters for multiple sets of regular waves

[0141]

[0142] Step S20: Perform wave generation test on each group of regular waves separately, and record the time from the start of wave generation to the first time the wave crest in the group of regular waves reaches the designated point of action, which is recorded as the wave crest propagation time.

[0143] Individual wave generation tests were conducted on 13 groups of regular waves, and the wave crest propagation time was recorded. The wave generation device was activated to generate a single group of regular waves, and the time it took for the first wave crest of each group to reach the designated point of action was recorded using a wave height sensor at a distance of 300m. This time was denoted as _____. Example data is given below:

[0144] Group 1 (T=3.0000s): t1=85.6s;

[0145] Group 2 (T=3.2500s): t2=87.2s;

[0146] Group 3 (T=3.5000s): t3=88.9s;

[0147] ...(The remaining groups are recorded according to the wave velocity pattern, with the longer the period, the greater the wave velocity, and the transmission time increasing sequentially).

[0148] Group 13 (T=6.0000s): t13=98.5s.

[0149] Step S30: Using the crest propagation time of one set of regular waves as a reference, calculate the crest propagation time difference between the other sets of regular waves and the reference set of regular waves.

[0150] For example, using group 1 as the baseline, calculate the peak propagation time difference between the remaining groups and the baseline group:

[0151] ;

[0152] ;

[0153] ...the remaining groups ;

[0154] S40. Determine the corrected start time of each group of regular waves based on the wave crest propagation time difference; according to the corrected start time, combined with the slow start coefficient and slow stop coefficient, obtain the corrected displacement expression of each group of regular waves; based on the corrected displacement expression, construct the instantaneous displacement formula of the synthetic wave.

[0155] Multiple sets of regular wave parameters and wave generation formulas are selected. The instantaneous displacement of a single set of regular waves is achieved through coefficient correction in three stages: gradual start-up, stabilization, and gradual stop. The formulas and coefficient definitions for each stage are as follows:

[0156] To avoid the impact distortion during the initial wave initiation phase, the instantaneous displacement formula for this phase is:

[0157] ;

[0158] In the formula, Let be the instantaneous displacement of the i-th group of regular waves at time t; Let be the period of the i-th wave group; The corrected start time of the i-th wave group is determined based on the time difference between the crest propagation of the regular wave and the reference group regular wave. The corrected start time of the reference group regular wave is 0. The easing coefficient corresponds to time t;

[0159] The expression for the easing coefficient is:

[0160] ;

[0161] in, The midpoint of the slowdown time, =0.005, which is a rate coefficient unique to the gradual start-up phase, ensuring that the coefficient smoothly increases from approximately 0 to 1, adapting to the gradual energy change requirements when the wave starts.

[0162] This invention standardizes the start-up process through a precise mathematical model, and its core benefit is ensuring a "soft start" for wave generation. This not only generates a highly smooth, distortion-free initial waveform but also avoids significant mechanical impact on the wave-generating device, extending its lifespan, while simultaneously improving the stability and control accuracy of the entire simulation system.

[0163] Once the easing coefficient reaches 1, it enters the stable propagation phase, which lasts for [duration not specified]. =400s (determined based on the number and period of waves), the coefficient remains at 1 during this stage, and the instantaneous displacement formula is:

[0164] ;

[0165] This formula is specifically designed to describe the stable propagation process of wave amplitude, ensuring that the wave shape remains consistent during propagation.

[0166] The stabilization phase; after the stabilization phase ends, to avoid distortion caused by the sudden cessation of wave movement, the instantaneous displacement formula for the stabilization phase is:

[0167] ;

[0168] In the formula, Let be the easing coefficient corresponding to time t.

[0169] The expression for the easing factor is:

[0170] ;

[0171] in, This is the reference time at the end of the stable phase. =0.001 is the pausing rate coefficient, which is a rate coefficient unique to the pausing phase. It ensures that the coefficient smoothly decreases from 1 to 0, so as to achieve the gradual decay of wave energy.

[0172] in The process for obtaining the corrected start-up time, determined based on the peak propagation time difference, is as follows:

[0173] The control module calculates the wave crest propagation time difference Δt for each group. i (i=2,3,…,13), and this time difference is incorporated into the starting parameters of the instantaneous displacement formula of the synthesized wave to determine the starting time parameter t of each group of regular waves in the synthesis formula. 0i The initial time parameter t in the synthesis formula for the first group of regular waves. 01 =0s; the initial time parameter t in the synthesis formula for the second group of regular waves. 02 =Δt2=1.6s; The initial time parameter t in the synthesis formula for the third group of regular waves. 03 =Δt3=3.3s; ... (the starting time parameter t in the synthesis formula for the remaining groups) 0i =corresponding to Δt i ).

[0174] The above parameters will serve as the time offset of each group of regular waves in the composite wave formula, ensuring that the phase and propagation characteristics of each group of waves in the composite wave are matched.

[0175] This invention effectively avoids the generation of complex reflected waves in the wave tank due to sudden wave cessation by using a fading coefficient. These reflected waves could interfere with subsequent experiments or take a long time to subside. By smoothly attenuating wave energy, it ensures a clean conclusion to the experiment, shortens the waiting time between experiments, and improves the utilization efficiency of large wave tanks.

[0176] The wave-generating device generates waves based on the formula for the instantaneous total displacement of the composite wave, which integrates time difference parameters. The specific phased formulas are as follows:

[0177] Slow start phase: ;

[0178] Stable phase: ;

[0179] Pause phase: ;

[0180] Each group of regular waves achieves synchronous generation and propagation through a synthesis formula, because t in the formula 0i The time difference is controlled so that the first wave peak arrives and superimposes simultaneously at the designated point of action at 300m in the 456m long water tank, and the composite wave reaches the peak of slamming. Subsequent waves continue to propagate according to the synthesis formula, and each group of waves alternates and superimposes according to its own period to simulate multiple slamming effects, which fits the loading scenario of large structures in the actual marine environment.

[0181] This invention combines multiple independent, regular waves into a single, powerful superimposed wave through precise time difference control and linear superposition, achieving synchronous focusing of wave crest energy at a designated location. This method offers high simulation accuracy and strong controllability, accurately reproducing extreme sea conditions that pose the greatest threat to marine engineering structures, and thus possesses significant engineering application value.

[0182] S50. Take the derivative of the instantaneous displacement formula of the composite wave twice to obtain the velocity curve and acceleration curve. If both the velocity curve and acceleration curve are continuous, the wave generation process is judged to be smooth and without abrupt changes.

[0183] Verifying the smoothness of the wave generation process: To ensure that the synthesized wave has no abrupt changes and a smooth shape during the generation process, the motion state of the synthesized wave needs to be mathematically verified.

[0184] Speed ​​continuity verification:

[0185] Taking the first derivative of the formula for the instantaneous total displacement of the composite wave, we obtain the velocity curve:

[0186] ;

[0187] in, The first derivative of the instantaneous total displacement of the composite wave with respect to time is the velocity curve. Let be the first derivative of the instantaneous displacement of the i-th group of regular waves at time t with respect to time;

[0188] The velocity formulas for a single wave group at different stages are as follows:

[0189] Slow start phase:

[0190] ;

[0191] ;

[0192] Stable phase:

[0193] ;

[0194] Pause phase:

[0195] ;

[0196] ;

[0197] in, ;

[0198] Verification shows that the left and right limits of the velocity curve are equal at the transition points from slow start to steady state and from steady state to slow stop. Therefore, the speed is continuous.

[0199] This invention provides a clear mathematical standard for evaluating the smoothness of the wave-generating process by introducing velocity continuity verification. It ensures that the total displacement function, assembled from the three-stage displacement formulas, has good first-order differentiability at the connection point, guaranteeing smooth and shock-free movement of the wave-generating plate. This is not only a prerequisite for generating high-quality, distortion-free waveforms, but also the technical foundation for ensuring the safe and stable operation of expensive, large-scale wave-generating equipment.

[0200] Acceleration continuity verification:

[0201] Taking the first derivative of the velocity curve (i.e., the second derivative of the displacement) yields the acceleration curve:

[0202] ;

[0203] in, This is the second derivative of the instantaneous total displacement of the composite wave with respect to time, i.e., the acceleration curve; Let be the second derivative of the instantaneous displacement of the i-th group of regular waves at time t with respect to time.

[0204] The acceleration formulas for a single wave at different stages are as follows:

[0205] Slow start phase:

[0206] ;

[0207] in, ;

[0208] Stable phase: ;

[0209] Pause phase:

[0210] ;

[0211] in, ;

[0212] Verification shows that the left and right limits of the acceleration curve are equal at the transition points from the slow start to the steady state and from the steady state to the slow stop phase. Therefore, the acceleration is continuous.

[0213] This invention provides a more rigorous and comprehensive evaluation standard for the smoothness of the wave generation process by adding acceleration continuity verification. It ensures that the force driving the wave-generating plate changes smoothly, minimizing mechanical vibration and noise to the greatest extent possible, thereby generating a target waveform with extremely high purity. Simultaneously, this precise control of the driving force effectively reduces mechanical fatigue and wear of the equipment, playing a crucial role in ensuring the long-term stable operation of large-scale, precision wave generation systems.

[0214] 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 technical solutions of the embodiments of the present invention.

Claims

1. A method for simulating slamming waves based on time difference regulation, characterized in that, include: S10. Select the target location of the simulated wave impacting the building as the designated point of action; At the designated point of action, multiple sets of regular waves with different periods are selected as simulation objects; wherein each set of regular waves includes a preset number of waves; S20. Perform wave generation test on each group of regular waves separately, and record the time from the start of wave generation to the first time the wave crest in the group of regular waves reaches the designated point of action, which is recorded as the wave crest propagation time; S30. Using the crest propagation time of one set of regular waves as a reference, calculate the crest propagation time difference between the other sets of regular waves and the reference set of regular waves; S40. Determine the corrected start time of each group of regular waves based on the wave crest propagation time difference; according to the corrected start time, combined with the slow start coefficient and slow stop coefficient, obtain the corrected displacement expression of each group of regular waves; based on the corrected displacement expression, construct the instantaneous displacement formula of the composite wave. S50. Take the first derivative of the instantaneous displacement formula of the composite wave to obtain the velocity curve; take the second derivative of the instantaneous displacement formula of the composite wave to obtain the acceleration curve; if both the velocity curve and the acceleration curve are continuous, then the wave generation process is determined to be smooth and without abrupt changes. The corrected displacement expressions include: instantaneous displacement formulas for the start-up phase, the steady-state phase, and the stopping phase; The instantaneous displacement formula for the gradual start-up phase is: ； In the formula, Let be the instantaneous displacement of the i-th group of regular waves at time t; Let be the period of the i-th wave group; The corrected start time for the i-th wave group is based on the time difference Δt between the crest propagation of the regular wave and the reference group of regular waves. i It is determined that the correction start time for the baseline group's regular wave is 0, and for the remaining groups... =Δt i ; The easing coefficient corresponds to time t; The amplitude reaches its maximum and then remains stable for a period of time. During the stable phase, the instantaneous displacement formula for the stable phase is: ； The instantaneous displacement formula for the easing phase is: ； In the formula, The easing coefficient corresponds to time t; The expression for the easing coefficient is: ； in, The midpoint of the easing time; =0.005, which is the start-up rate coefficient; The expression for the easing factor is: ； in, =0.001 is the stopping rate coefficient. This is the reference time at the end of the stable phase.

2. The slamming wave simulation method based on time difference control according to claim 1, characterized in that, Each set of regular waves contains 10-50 waves, and the number of waves in each set is the same.

3. The slamming wave simulation method based on time difference control according to claim 1, characterized in that: The total instantaneous displacement of the composite wave during the gradual onset phase is the sum of the instantaneous displacements of each set of regular waves during the gradual onset phase, that is: ； in, Let i be the period of the i-th wave group. The corrected start time for the i-th wave group is based on the wave crest propagation time difference Δt. i Set the baseline group to 0, and the other groups to 0. =Δt i ; The total number of groups of regular waves; Stable phase: The total instantaneous displacement of the composite wave is the sum of the instantaneous displacements of each set of regular waves during the stable phase, that is: ； Among them, the duration of the stable phase Determined by the number and period of waves, the amplitude of each group of waves remains at its maximum during this stage; Descent phase: The instantaneous total displacement of the composite wave is the sum of the instantaneous displacements of each group of regular waves during the descent phase, that is: ； in, The instantaneous total displacement of the synthesized wave.

4. The slamming wave simulation method based on time difference control according to claim 3, characterized in that, The velocity curve is the first derivative of the instantaneous total displacement of the composite wave with respect to time, expressed as: ； in, The first derivative of the instantaneous total displacement of the composite wave with respect to time is the velocity curve. Let be the first derivative of the instantaneous displacement of the i-th group of regular waves at time t with respect to time; The velocity formula for a single wave group in the initial stage is: ； in, The lag coefficient The first derivative with respect to time; The stable phase is as follows: ； The easing phase is as follows: ； ； in, Delay coefficient The first derivative with respect to time; This indicates a cyclical index.

5. The slamming wave simulation method based on time difference control according to claim 4, characterized in that, The acceleration curve is the second derivative of the instantaneous total displacement of the composite wave with respect to time, expressed as: ； in, This is the second derivative of the instantaneous total displacement of the composite wave with respect to time, i.e., the acceleration curve; Let be the second derivative of the instantaneous displacement of the i-th group of regular waves at time t with respect to time; The acceleration formula for a single wave in the initial stage is: ； in, The lag coefficient The second derivative with respect to time; The stable phase is as follows: ； The easing phase is as follows: ； in, Delay coefficient The second derivative with respect to time.

6. The slamming wave simulation method based on time difference control according to claim 1, characterized in that, The criteria for judging a smooth wave-making process without abrupt changes are: at the transition point from the gradual rise to the steady state and at the transition point from the steady state to the gradual stop, the left and right limit values ​​of the velocity curve are equal, and the left and right limit values ​​of the acceleration curve are equal.

7. A slamming wave simulation device based on time difference regulation, characterized in that, A method for simulating slamming waves based on time difference control, as described in any one of claims 1-6, comprises: Wave tanks: used to provide space for wave generation and propagation; Wave generating device: Installed at one end of the wave tank, it is used to generate periodic regular waves according to the wave generating formula, and can be operated according to the slow start and slow stop formula and the determined wave amplitude maintenance time. Wave crest monitoring module: Installed at a designated point of action, it detects the time when the wave crest reaches that point; Control module: Electrically connected to the wave generator and the wave crest monitoring module respectively, used to record the wave crest propagation time of each group of waves, calculate the time difference, adjust the start time of the wave generator and the instantaneous displacement of the waves according to the synthetic wave formula, and control the parameters of the slow start, wave amplitude maintenance and slow stop stages.

Images