An analysis method and system for strongly nonlinear waves

Abstract

The application provides a strong nonlinear wave analysis method and system, comprising the following steps: obtaining time history data of a strong nonlinear wave to be analyzed; inverting wave generation on the time history data of the strong nonlinear wave, and obtaining four waves with different phases according to the wave generation result; separating high-order terms of the four waves with different phases, and generating high-order terms of the waves according to the separation result; analyzing the high-order terms of the waves according to characteristic parameters, and determining the influence of the characteristic parameters on the high-order terms of the waves according to the analysis result; the application has the following beneficial effects: the high-order terms of the waves can be generated by separating the high-order terms of the four waves with different phases obtained from the time history data of the strong nonlinear wave, the influence of wave height and wave steepness on the high-order terms of the waves can be compared, the influence of the wave height and the wave steepness on the strong nonlinear wave can be obtained, and data reference for the influence of the characteristic parameters of the strong nonlinear wave on the strong nonlinear wave is provided.

Description

Technical Field

[0001] This invention relates to the field of strong nonlinear wave technology, and in particular to an analysis method and system for strong nonlinear waves. Background Technology

[0002] With the development and application of marine resources in recent years, the prediction of motion and loads on marine structures such as fixed platforms, floating platforms, and ships in waves has become particularly important. For example, the prediction of ship motion under wave loads can provide a data foundation for ship design and stability estimation; while the prediction of stress on structures under wave loads can identify areas prone to fatigue failure and provide optimization solutions for structural design. At the same time, as marine development gradually moves towards the deep sea, higher requirements are placed on the durability and stability of structures in the ocean. This has led to research on structures in waves that is no longer limited to regular waves and small-amplitude waves. The waves are not only more complex, but also more varied in the deep sea. In recent years, more and more scholars and engineers have discovered the existence of abnormal waves and extreme waves. These waves exhibit significant nonlinear phenomena, with high and steep waves that appear randomly but can accumulate enormous energy in an instant. If not studied and prevented, they can not only cause great motion responses in marine structures, but also cause great damage to the structure of marine buildings, and even lead to accidents. Therefore, studying the characteristic parameters in strong nonlinear waves is of great significance for studying the interaction between strong nonlinear waves and structures. However, at present, there is little research on the influence of characteristic parameters on strong nonlinear waves.

[0003] Most waves in strongly nonlinear waves are strong instantaneous events. The traditional fast Fourier transform method is not suitable as a method for studying hydrodynamic parameters in strongly nonlinear waves. Previous phase separation methods have been used to study the interaction between waves and structures, that is, to separate the nonlinear terms of the forces and motions of the structure. However, the case of the influence of wave characteristic parameters on wave nonlinearity is limited to regular waves. At present, there are few research methods related to strongly nonlinear waves. Summary of the Invention

[0004] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide an analysis method and system for strong nonlinear waves, which solves the problem of the lack of research on the influence of characteristic parameters on strong nonlinear waves in the prior art.

[0005] To achieve the above and other related objectives, the present invention provides the following technical solution:

[0006] A method for analyzing strong nonlinear waves includes the following steps: acquiring time history data of the strong nonlinear wave to be analyzed; performing wave generation inversion on the time history data of the strong nonlinear wave, and obtaining four waves with different phases based on the wave generation results; separating higher-order terms of the four waves with different phases, and generating higher-order terms of the waves based on the separation results, wherein the higher-order terms of the waves include first-order, second-order, third-order, and fourth-order terms of the waves; analyzing the higher-order terms of the waves based on characteristic parameters, and determining the influence of the characteristic parameters on the higher-order terms of the waves based on the analysis results, wherein the characteristic parameters include wave height and wave steepness.

[0007] An embodiment of the present invention also provides an analysis system for strong nonlinear waves, comprising: an acquisition module for acquiring time history data of the strong nonlinear wave to be analyzed; an inversion wave generation module for performing inversion wave generation on the time history data of the strong nonlinear wave, and obtaining four waves with different phases based on the wave generation results; a higher-order term separation module for separating higher-order terms of the four waves with different phases, and generating higher-order terms of the waves based on the separation results, wherein the higher-order terms of the waves include first-order, second-order, third-order, and fourth-order terms of the waves; and an analysis module for analyzing the higher-order terms of the waves based on characteristic parameters, and determining the influence of the characteristic parameters on the higher-order terms of the waves based on the analysis results, wherein the characteristic parameters include wave height and wave steepness.

[0008] Embodiments of the present invention also provide a server, comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to perform the analysis method for strong nonlinear waves as described above.

[0009] Embodiments of the present invention also provide a computer-readable storage medium storing a computer program that, when executed by a processor, implements the analysis method for strong nonlinear waves as described above.

[0010] In one embodiment of the present invention, the step of inverting and generating waves from the time history data of a strong nonlinear wave to obtain four waves with different phases based on the wave generation results includes: performing component decomposition on the time history data of the strong nonlinear wave, determining the components of the original wave corresponding to the strong nonlinear wave based on the decomposition results, wherein the components of the original wave include frequency, amplitude, and phase; keeping the frequency and amplitude unchanged while transforming the phase, and determining the components of the wave after the phase change based on the transformation results.

[0011] The phase is transformed by 90°, 180°, and 270°. Wave generation is performed on the components of the original wave and the components of the wave after phase change. Based on the wave generation results, four waves with different phases are generated, namely 0°, 90°, 180°, and 270°. This technical solution obtains the components of the original wave corresponding to the strong nonlinear wave by performing component decomposition on the time history data of the strong nonlinear wave. Then, the phase is transformed by 90°, 180°, and 270°, and wave generation is performed on the components of the original wave and the components of the wave after phase change, thereby generating four waves with different phases.

[0012] In one embodiment of the present invention, the inverse fast Fourier transform method is used to decompose the time history data of a strong nonlinear wave into components, and the components of the original wave corresponding to the strong nonlinear wave are determined based on the decomposition results.

[0013] In one embodiment of the present invention, a higher-order spectral method is used to generate waves from the components of the original wave and the components of the wave after phase change, and four waves with different phases are generated based on the wave generation results. The higher-order spectral method is a numerical pool method.

[0014] In one embodiment of the present invention, the step of separating higher-order terms of four waves with different phases and generating higher-order terms of the waves based on the separation results includes: generating higher-order terms of the waves according to the following formula: considering a set of inviscid and irrotational waves with wave height A and phase... Waves can be expanded using Stokes perturbations: Where f ij The coefficients of the Fourier series of η are represented by i, where i is the order of the amplitude and j is the order of the frequency.

[0015] Therefore, waves with four different phases can be processed using the following formula: (η 0 -H(η 90 )-η 180 +H(η 270 )) / 4=η 11 +η 31 ;(η 0 -η 90 +η 180 -η 270 ) / 4=η 22 +η 42 ;(η 0 +H(η 90 )-η 180 -H(η 270 )) / 4=η 33 ;(η 0 +η 90 +η 180 +η270 ) / 4=η 20 +η 40 +η 44 In this formula, the terms on the right-hand side, from top to bottom, represent the first, second, third, and fourth order terms of the wave in the time domain, η. 0 η 90 η 180 and η 270 These represent the original wave and the waves with phase adjustments of 90°, 180°, and 270°, respectively, with H() representing the Hilbert transform equation.

[0016] In one embodiment of the present invention, after separating the higher-order terms of the four waves with different phases and generating the higher-order terms of the waves based on the separation results, and before analyzing the higher-order terms of the waves based on the characteristic parameters and determining the influence of the characteristic parameters on the higher-order terms of the waves based on the analysis results, the method further includes: preprocessing the higher-order terms of the waves, wherein the preprocessing includes Fast Fourier Transform and dimensionless processing. This technical solution, by performing Fast Fourier Transform and dimensionless processing on the higher-order terms of the waves, can determine that the peak value of the wave amplitude will be focused at each frequency peak, which facilitates subsequent analysis of the higher-order terms of the waves based on the characteristic parameters.

[0017] As described above, the analysis method and system for strong nonlinear waves of the present invention have the following beneficial effects: The present invention generates waves by inverting the acquired time history data of the strong nonlinear wave to be analyzed, thereby obtaining waves with four different phases. Then, higher-order terms are separated from the four waves with different phases, thereby generating first-order, second-order, third-order, and fourth-order terms of the waves. Then, by comparing the influence of different wave heights and steepness on the higher-order terms of the waves, the influence of wave height and steepness on the strong nonlinear wave can be obtained, thus providing data reference for the influence of the characteristic parameters of the strong nonlinear wave on the strong nonlinear wave. Attached Figure Description

[0018] Figure 1 This is a flowchart of the analysis method for strong nonlinear waves in the first embodiment of the present invention;

[0019] Figure 2 This is a flowchart of the analysis method for strong nonlinear waves in the second embodiment of the present invention;

[0020] Figure 3 This is a schematic diagram of the analysis system for strong nonlinear waves in the third embodiment of the present invention;

[0021] Figure 4 This is a schematic diagram of an electronic device according to the fourth embodiment of the present invention;

[0022] Figure 5This is a detailed flowchart of the analysis method for strong nonlinear waves in this invention;

[0023] Figure 6 This is a schematic diagram of the strongly nonlinear primary wave simulated using the higher-order spectral method in this invention;

[0024] Figure 7 This is a schematic diagram of the strongly nonlinear primary wave directly provided in the laboratory in this invention;

[0025] Figure 8 This is a schematic diagram of the first-order components of waves with different wave heights after dimensionless processing in this invention.

[0026] Figure 9 This is a schematic diagram of the second-order components of waves with different wave heights after dimensionless processing in this invention.

[0027] Figure 10 This is a schematic diagram of the third-order components of waves with different wave heights after dimensionless processing in this invention.

[0028] Figure 11 This is a schematic diagram of the fourth-order components of waves with different wave heights after dimensionless processing in this invention.

[0029] Figure 12 This is a schematic diagram of the first-order components of waves with different wave steepness after dimensionless processing in this invention.

[0030] Figure 13 This is a schematic diagram of the second-order components of waves with different wave steepness after dimensionless processing in this invention.

[0031] Figure 14 This is a schematic diagram of the third-order components of waves with different steepness after dimensionless processing in this invention.

[0032] Figure 15 This is a schematic diagram of the fourth-order components of waves with different steepness after dimensionless processing in this invention. Detailed Implementation

[0033] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. It should be noted that, unless otherwise specified, the following embodiments and features described herein can be combined with each other.

[0034] The first embodiment of the present invention relates to a method for analyzing strongly nonlinear waves. The process is as follows: Figure 1 As shown, the details are as follows:

[0035] Step 101: Obtain the time history data of the strong nonlinear wave to be analyzed;

[0036] Step 102: Invert the time history data of the strong nonlinear wave to generate waves, and obtain four waves with different phases based on the wave generation results.

[0037] Specifically, firstly, the time history data of the strong nonlinear wave is decomposed into components. Based on the decomposition results, the components of the original wave corresponding to the strong nonlinear wave are determined, including frequency, amplitude, and phase. Then, while keeping the frequency and amplitude unchanged, the phase is transformed. Based on the transformation results, the components of the wave after phase change are determined, with phase transformations of 90°, 180°, and 270°. Finally, wave generation is performed on the components of the original wave and the components of the wave after phase change. Based on the wave generation results, four waves with different phases are generated, namely 0°, 90°, 180°, and 270°.

[0038] Step 103: Separate the higher-order terms of the four waves with different phases, and generate the higher-order terms of the waves based on the separation results.

[0039] Specifically, the higher-order terms of the wave include the first-order, second-order, third-order, and fourth-order terms, and are generated according to the following formula: Considering a set of inviscid and irrotational waves with wave height A and phase... Waves can be expanded using Stokes perturbations: Where f ij The coefficients of the Fourier series of η are represented by i, where i is the order of the amplitude and j is the order of the frequency.

[0040] Therefore, waves with four different phases can be processed using the following formula: (η 0 -H(η 90 )-η 180 +H(η 270 )) / 4=η 11 +η 31 ;(η 0 -η 90 +η 180 -η 270 ) / 4=η 22 +η 42 ;(η 0 +H(η 90 )-η 180 -H(η 270 )) / 4=η 33 ;(η 0 +η 90 +η 180 +η 270 ) / 4=η 20 +η 40 +η 44In this formula, the terms on the right-hand side, from top to bottom, represent the first, second, third, and fourth order terms of the wave in the time domain, η. 0 η 90 η 180 and η 270 These represent the original wave and the waves with phase adjustments of 90°, 180°, and 270°, respectively, with H() representing the Hilbert transform equation.

[0041] Step 104: Analyze the higher-order terms of the wave based on the characteristic parameters, and determine the influence of the characteristic parameters on the higher-order terms of the wave based on the analysis results.

[0042] Specifically, the characteristic parameters include wave height and wave steepness.

[0043] In practical applications, the specific implementation process of the embodiments is described in detail below. It should be noted that the original wave used directly in the laboratory is a strong nonlinear wave. In the laboratory, it is not necessary to decompose the time history curve of the strong nonlinear wave, and the specific values ​​of wave height and wave steepness can be known from the original wave.

[0044] 1. Comparative Analysis of Higher-Order Term Separation in Focused Waves with Different Wave Heights: This embodiment is based on a standard mode focused wave. The wave conditions for this embodiment are shown in Table 1, where the wave height for the 12BT condition is greater than that for the 11BT condition.

[0045] Table 1 Focusing on the operating conditions of the beacon model

[0046]

[0047] This embodiment uses a higher-order spectral method to compare with experimental results, for example... Figure 6 and Figure 7 As shown, this example demonstrates that the higher-order spectral method used can accurately simulate strong nonlinear waves, ensuring the accuracy and reliability of the original wave results. Based on the higher-order term separation method of wave characteristic parameters used in this invention, the separated first-order (linear), second-order, third-order, and fourth-order terms were compared, as shown below. Figure 8 , Figure 9 , Figure 10 and Figure 11 As shown.

[0048] from Figure 8 As can be seen, after dimensionless processing, the first-order components of the waves cluster around f / fp = 1. The dimensionless amplitudes at the first order are consistent for waves with different wave heights, indicating that wave height has little impact on the first-order linear components of the waves. Figure 9 As can be seen from this, the second-order components of the wave are clustered around f / fp=2, indicating that the amplitude reflects the second-order nonlinear components of the wave. It can be seen that the greater the wave height, the greater the amplitude of the second-order components. Figure 10 and Figure 11 The third and fourth order components of the wave are shown respectively. The amplitude of 12BT at both the third and fourth order is greater than that of 11BT. Therefore, it can be seen that the higher the wave height, the stronger the nonlinearity of the wave, which is specifically manifested in the larger amplitudes of the second, third and fourth order components of the wave.

[0049] 2. Comparative Analysis of Higher-Order Term Separation for Stokes Fifth-Order Waves with Different Wave Steepness: This embodiment is based on Stokes fifth-order waves generated in a laboratory. The wave conditions for this embodiment are shown in Table 2, where the wave steepness of condition R1 is greater than that of condition R2.

[0050] Table 2 Stokes Fifth-Order Wave Condition Table

[0051]

[0052] Based on the higher-order term separation method of wave characteristic parameters adopted in this invention, the separated first-order (linear), second-order, third-order, and fourth-order terms were compared, such as... Figure 12 , Figure 13 , Figure 14 and Figure 15 As shown.

[0053] from Figure 12 As can be seen, the first-order components of the wave are clustered around f / fp = 1; the steeper the wave, the larger the first-order components. Figure 13 As can be seen from this, the second-order components of the wave are clustered around f / fp=2, indicating that the amplitude reflects the second-order nonlinear components of the wave. The steeper the wave, the smaller the amplitude of the second-order components. Figure 14 and Figure 15 The third and fourth order components of the wave are shown respectively. The amplitude of R1 at both the third and fourth order is greater than that of R2. Therefore, the steeper the wave, the greater the linear and third and fourth order components of the wave, while the second order component decreases.

[0054] This implementation method can generate waves by inverting the acquired time history data of the strong nonlinear wave to be analyzed, thereby obtaining four waves with different phases. Then, higher-order terms are separated from the four waves with different phases, thereby generating first-order, second-order, third-order, and fourth-order terms of the waves. Then, by comparing the influence of different wave heights and steepness on the higher-order terms of the waves, the influence of wave height and steepness on the strong nonlinear wave can be obtained, thus providing data reference for the influence of the characteristic parameters of the strong nonlinear wave on the strong nonlinear wave.

[0055] The second embodiment of the present invention relates to an analysis method for strong nonlinear waves. The second embodiment is a detailed description of the first embodiment as a whole. The main detailed description is that in the second embodiment of the present invention, an implementation method is specified, which describes the specific process of inverting wave generation from the time history data of strong nonlinear waves and obtaining waves with four different phases based on the wave generation results.

[0056] Please refer to this implementation method. Figure 2 The process includes the following steps, which are explained below:

[0057] Step 201 is similar to step 101 in the first embodiment, and will not be described again here.

[0058] Step 202: Perform component decomposition on the time history data of the strong nonlinear wave, and determine the components of the original wave corresponding to the strong nonlinear wave based on the decomposition results.

[0059] Specifically, the components of the original wave include frequency, amplitude, and phase.

[0060] Furthermore, by using the inverse fast Fourier transform (IFFT) method to decompose the time history curve of an existing strongly nonlinear wave into its components, we can obtain the following: The strongly nonlinear wave can be represented by a continuous function x(t) in the time domain. After the IFFT, we get: Where X(f) is the amplitude after inverse fast Fourier transform, f is the frequency, j represents the imaginary part, and the angle between the imaginary and real parts is the phase. Thus, the components of the original wave are obtained through inverse fast Fourier transform.

[0061] Step 203: Keep the frequency and amplitude unchanged, transform the phase, and determine the components of the wave after the phase change based on the transformation result.

[0062] Specifically, the phase undergoes transformations of 90°, 180°, and 270°.

[0063] Step 204: Generate waves based on the components of the original wave and the components of the wave after phase change, and generate four waves with different phases based on the wave generation results.

[0064] Specifically, the four different phases are 0°, 90°, 180° and 270°. The higher-order spectral method is used to generate waves based on the components of the original wave and the components of the wave after the phase change. The higher-order spectral method adopts the numerical pool method.

[0065] Furthermore, the main calculation steps for wave generation using the numerical water tank method are as follows:

[0066] After obtaining the components of the original wave from the time-history curve of the strongly nonlinear wave through inverse fast Fourier transform, the wave generation result at this point differs in phase from the target wave. Where k i The wave number for each wave component, x f Location of the measurement point;

[0067] Step 1: Apply higher-order spectral methods to perform numerical water tank simulation wave generation: φ = φ tank +φ add , where φ tank The velocity potential within the original region with a free liquid surface, φ add To disregard the free surface, a new velocity potential considering the wave-generating plate is added. Therefore, within the computational domain, the newly added velocity potential φ... add It also satisfies the Laplace equation; based on the higher-order spectral method, a surface velocity potential is introduced: Φ s (x,y,t)=Φ[x,y,η(x,y,t),t], where z=η(x,y,t) represents the free surface, which is assumed to be continuous and single-valued, and the surface velocity potential Φ s The spatial derivatives of time and level are: The gradient operator in the formula represents the horizontal gradient; therefore, the kinematic and dynamic boundary conditions on the free surface can be represented by Φ. s η and Φ z express: Under specific boundary conditions, it can be and Φ s And η can be directly expressed, thus making the above two equations a closed system of equations describing the evolution. In this way, once the initial value Φ of the wavefront is given, s (x,y,0) and η(x,y,0) can be continuously calculated. This method is fast and simple and can quickly generate strong nonlinear waves.

[0068] The second step is to adjust the phase of each wave component and continue to use the above steps to generate waves, finally obtaining four waves with different phases, including the original wave.

[0069] Step 205 is similar to step 103 in the first embodiment, and will not be described again here.

[0070] Step 206: Preprocess the higher-order terms of the wave.

[0071] Specifically, the preprocessing includes Fast Fourier Transform and dimensionless transformation.

[0072] Furthermore, after regenerating the higher-order terms of the wave, corresponding to the four formulas in step 103, the right-hand side terms of the four formulas represent the first-order, second-order, third-order, and fourth-order terms of the wave in the time domain, respectively. Then, a fast Fourier transform is performed on these separated higher-order terms, η=∫f(t)e -iωt In other words, the component distribution of waves in the frequency domain can be obtained through Fast Fourier Transform. At the same time, for comparison, the horizontal axis (frequency) and the vertical axis (amplitude) are dimensionless, that is, the horizontal axis is divided by the peak frequency of the spectrum, and the vertical axis is divided by the sum of the amplitudes of all wave components. After the dimensionless processing, the peak value of the amplitude will be focused at the peak value of each frequency. That is, the peak value of the first-order term is focused at the peak value of the first-order frequency, and the peak value of the second-order term is focused at the peak value of the second-order frequency. In this way, even waves with different characteristic parameters can have the same trend. Assuming that there are two waves with different wave heights, the nonlinear influence of characteristic parameters on waves can be obtained by comparing the amplitude values ​​at the same peak value.

[0073] Step 207 is similar to step 104 in the first embodiment, and will not be described again here. For a detailed flowchart of the analysis method for strong nonlinear waves of the present invention, please refer to [link / reference needed]. Figure 5 .

[0074] This implementation method can obtain the components of the original wave corresponding to the strong nonlinear wave by performing component decomposition on the time history data of the strong nonlinear wave. Then, the phase is transformed by 90°, 180° and 270°. Wave generation is then performed on the components of the original wave and the components of the wave after phase change, thereby generating four waves with different phases.

[0075] The third embodiment of the present invention relates to an analysis system for strongly nonlinear waves; please refer to [link to relevant documentation]. Figure 3 ,include:

[0076] The acquisition module is used to acquire the time history data of the strong nonlinear wave to be analyzed.

[0077] The inversion wave generation module is used to invert and generate waves from the time history data of strongly nonlinear waves, and obtain waves with four different phases based on the wave generation results.

[0078] The higher-order term separation module is used to separate the higher-order terms of waves in four different phases and generate higher-order terms of the waves based on the separation results. The higher-order terms of the waves include the first-order, second-order, third-order, and fourth-order terms of the waves.

[0079] The analysis module is used to analyze the higher-order terms of waves based on characteristic parameters, and to determine the influence of characteristic parameters on the higher-order terms of waves based on the analysis results. The characteristic parameters include wave height and wave steepness.

[0080] It is not difficult to see that this embodiment is a system implementation corresponding to the first embodiment, and this embodiment can be implemented in conjunction with the first embodiment. The relevant technical details mentioned in the first embodiment are still valid in this embodiment, and will not be repeated here to reduce repetition. Accordingly, the relevant technical details mentioned in this embodiment can also be applied to the first embodiment.

[0081] It is worth mentioning that all modules involved in this embodiment are logical modules. In practical applications, a logical unit can be a physical unit, a part of a physical unit, or a combination of multiple physical units. Furthermore, to highlight the innovative aspects of this invention, this embodiment does not introduce units that are not closely related to solving the technical problem proposed by this invention; however, this does not mean that other units are absent from this embodiment.

[0082] The fourth embodiment of the present invention relates to a server; please refer to [link / reference]. Figure 4 ,include:

[0083] At least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to perform the above-described method for analyzing strong nonlinear waves.

[0084] The memory and processor are connected via a bus, which can include any number of interconnecting buses and bridges, connecting various circuits of one or more processors and memories. The bus can also connect various other circuits, such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art and will not be described further herein. The bus interface provides an interface between the bus and the transceiver. The transceiver can be a single element or multiple elements, such as multiple receivers and transmitters, providing a unit for communicating with various other devices over a transmission medium. Data processed by the processor is transmitted over the wireless medium via an antenna, which further receives data and transmits it to the processor.

[0085] The processor manages the bus and general processing, and also provides various functions, including timing, peripheral interfaces, voltage regulation, power management, and other control functions. Memory is used to store data used by the processor during operation.

[0086] The fifth embodiment of the present invention relates to a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described method embodiments.

[0087] That is, those skilled in the art will understand that all or part of the steps in the methods of the above embodiments can be implemented by a program instructing related hardware. This program is stored in a storage medium and includes several instructions to cause a device (which may be a microcontroller, chip, etc.) or processor to execute all or part of the steps of the methods of the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as a USB flash drive, a portable hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0088] This invention generates waves by inverting the acquired time-history data of a strongly nonlinear wave to be analyzed, thereby obtaining four waves with different phases. Then, higher-order terms are separated from the four waves with different phases, thereby generating first-order, second-order, third-order, and fourth-order terms of the waves. Then, by comparing the influence of different wave heights and steepness on the higher-order terms of the waves, the influence of wave height and steepness on strongly nonlinear waves can be obtained, thus providing data reference for the influence of characteristic parameters of strongly nonlinear waves on strongly nonlinear waves.

[0089] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. All equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this invention should still be covered by the claims of this invention.

Claims

1. A method for analyzing strongly nonlinear waves, characterized in that, Includes the following steps: Obtain the time history data of the strong nonlinear wave to be analyzed; Wave generation was performed by inverting the time history data of a strongly nonlinear wave, and four waves with different phases were obtained based on the wave generation results. Higher-order terms are separated from waves of four different phases, and higher-order terms of the waves are generated based on the separation results. The higher-order terms of the waves include first-order, second-order, third-order, and fourth-order terms. The higher-order terms of the wave are analyzed based on the characteristic parameters, and the influence of the characteristic parameters on the higher-order terms of the wave is determined based on the analysis results. The characteristic parameters include the wave height and wave steepness. The step of separating higher-order terms of waves in four different phases and generating higher-order terms of the waves based on the separation results includes: The higher-order terms of the wave are generated using the following formula: Considering a set of inviscid and irrotational waves with a wave height of Phase is The waves are unfolded using Stokes perturbations: ,in represent The coefficients of the Fourier series, The order of the amplitude. The order of the frequency; Therefore, the waves with four different phases are processed using the following formula: ； ； ； ； In this formula, the terms on the right-hand side, from top to bottom, represent the first-order, second-order, third-order, and fourth-order terms of the wave in the time domain. , , and These represent the original wave and the waves adjusted to 90°, 180°, and 270° phases, respectively. This represents the Hilbert transformation equation.

2. The method for analyzing strong nonlinear waves according to claim 1, characterized in that: The process involves inverting the time history data of a strongly nonlinear wave to generate waves, resulting in waves with four different phases, including: The time history data of a strong nonlinear wave is decomposed into components, and the components of the original wave corresponding to the strong nonlinear wave are determined based on the decomposition results. The components of the original wave include frequency, amplitude, and phase. While keeping the frequency and amplitude constant, the phase is transformed, and the components of the wave after the phase change are determined based on the transformation result. The phase is transformed by 90°, 180°, and 270°. Wave generation is performed on the components of the original wave and the components of the wave after phase change. Based on the wave generation results, four waves with different phases are generated, namely 0°, 90°, 180° and 270°.

3. The method for analyzing strong nonlinear waves according to claim 2, characterized in that: The time history data of a strong nonlinear wave is decomposed using the inverse fast Fourier transform method, and the components of the original wave corresponding to the strong nonlinear wave are determined based on the decomposition results.

4. The method for analyzing strong nonlinear waves according to claim 2, characterized in that: The higher-order spectral method is used to generate waves from the components of the original wave and the components of the wave after phase change. Based on the wave generation results, four waves with different phases are generated. The higher-order spectral method is a numerical pool method.

5. The method for analyzing strong nonlinear waves according to claim 1, characterized in that: After separating the higher-order terms of the waves in four different phases and generating the higher-order terms of the waves based on the separation results, and before analyzing the higher-order terms of the waves based on the characteristic parameters and determining the influence of the characteristic parameters on the higher-order terms of the waves based on the analysis results, the method further includes: The higher-order terms of the waves are preprocessed, wherein the preprocessing includes fast Fourier transform and dimensionless transformation.

6. A system for analyzing strongly nonlinear waves, characterized in that: include: The acquisition module is used to acquire the time history data of the strong nonlinear wave to be analyzed. The inversion wave generation module is used to invert and generate waves from the time history data of strongly nonlinear waves, and obtain waves with four different phases based on the wave generation results. The higher-order term separation module is used to separate the higher-order terms of waves in four different phases and generate higher-order terms of the waves based on the separation results. The higher-order terms of the waves include the first-order, second-order, third-order, and fourth-order terms of the waves. The analysis module is used to analyze the higher-order terms of waves based on characteristic parameters, and to determine the influence of the characteristic parameters on the higher-order terms of waves based on the analysis results. The characteristic parameters include wave height and wave steepness. The step of separating higher-order terms of waves in four different phases and generating higher-order terms of the waves based on the separation results includes: The higher-order terms of the wave are generated using the following formula: Considering a set of inviscid and irrotational waves with a wave height of Phase is The waves are unfolded using Stokes perturbations: ,in represent The coefficients of the Fourier series, The order of the amplitude. The order of the frequency; Therefore, the waves with four different phases are processed using the following formula: ； ； ； ； In this formula, the terms on the right-hand side, from top to bottom, represent the first-order, second-order, third-order, and fourth-order terms of the wave in the time domain. , , and These represent the original wave and the waves adjusted to 90°, 180°, and 270° phases, respectively. This represents the Hilbert transformation equation.

7. A server, characterized in that, include: At least one processor; as well as, A memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor to enable the at least one processor to perform a method for analyzing strong nonlinear waves as described in any one of claims 1 to 5.

8. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the method for analyzing strong nonlinear waves as described in any one of claims 1 to 5.

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