CN-121997830-A - Abnormal wave generation method based on in-band energy transfer

CN121997830ACN 121997830 ACN121997830 ACN 121997830ACN-121997830-A

Abstract

The application provides a method for generating a malformed wave based on in-band energy transfer, which comprises the steps of determining a wave surface expression of a first background wave with energy density distribution consistent with a target energy spectrum in each frequency band, determining the wave surface expression of a target focusing wave based on a wave generation target, carrying out in-band energy transfer operation on the first background wave under the total energy constraint of the focusing frequency band to generate a second background wave if the energy of the first background wave in the focusing frequency band is larger than the energy of the target focusing wave in the focusing frequency band, otherwise, re-comparing the energy of the first background wave and the energy of the target focusing wave in the focusing frequency band after the target energy spectrum lifting operation or the target focusing wave updating operation, and superposing the target focusing wave by the second background wave to generate the malformed wave. The method provided by the application can ensure that the malformed wave which meets the amplitude target of the focused wave component and is attached to the energy distribution characteristic of the actual wave can be constructed.

Inventors

CUI TING
HE GUANGHUA
ZHAO WEIDONG
Luan Zhengxiao

Assignees

哈尔滨工业大学（威海）

Dates

Publication Date: 20260508
Application Date: 20260128

Claims (10)

1. A method of generating a malformed wave based on in-band energy transfer, comprising the steps of: S1, determining a wave surface expression of a first background wave based on a target energy spectrum, wherein the energy density distribution of the first background wave in each frequency band is consistent with the target energy spectrum; S2, determining a wave surface expression of a target focused wave based on a wave-making target, wherein the wave-making target at least comprises a focusing moment, a focusing position, a focusing frequency band and wave heights of all wave components of the target focused wave; S3, if the energy of the first background wave in the focusing frequency band is larger than the energy of the target focusing wave in the focusing frequency band, carrying out in-band energy transfer operation on the first background wave under the total energy constraint of the focusing frequency band to generate a second background wave, otherwise, returning to the step S3 after the target energy spectrum lifting operation or the target focusing wave updating operation; s4, superposing the target focusing wave through the second background wave to generate a malformed wave.
2. The method of generating a malformed wave based on in-band energy transfer of claim 1, wherein the wave surface expression of the first background wave The method comprises the following steps: , Wherein, the 、 The position variable and the time variable are respectively, To make up the total number of wave components of the first background wave, 、、、 Respectively the first background wave Wave height, wave number, angular frequency and random phase of each wave component, and wave height of each wave component Based on the angular frequency of each wave component of the target energy spectrum The value at which is determined.
3. The method for generating a malformed wave based on in-band energy transfer of claim 2, wherein the wave surface expression of the target focused wave The method comprises the following steps: , Wherein, the 、、 Respectively the first of the target focused waves Wave height, wave number and angular frequency of the individual wave components, And The focus position and focus time of the target focused wave, 、 The minimum sequence number and the maximum sequence number of wave components constituting the target focused wave, respectively.
4. A method of generating a malformed wave based on in-band energy transfer according to claim 3, wherein the in-band energy transfer operation comprises the steps of: First, solving an equation shown in the following formula to obtain energy of the second background wave in the focusing frequency band : , Wherein, the For the energy of the first background wave in the focal band, For the energy of the target focused wave in the focused frequency band, To reflect 、 A coefficient of coherence between; second, the compression factor is determined based on the following formula : ; Third, determining wave height of each background wave component in the focusing frequency band after energy transfer based on the following steps : ; Fourth, generating a second background wave based on the following formula : 。
5. The method of generating an in-band energy transfer based malformed wave of claim 4, wherein the first background wave is energy in a focused frequency band And the energy of the target focused wave in the focused frequency band The method comprises the following steps of: , 。
6. The method for generating an in-band energy transfer-based malformed wave according to claim 4, wherein, The absolute value of (2) is 0.2 or less.
7. The method for generating an in-band energy transfer-based malformed wave according to claim 4, wherein, The target energy spectrum lifting operation comprises the following steps: A1, integrally lifting a current target energy spectrum; A2, re-determining a wave surface expression of the first background wave based on the overall lifted target energy spectrum.
8. The method for generating a malformed wave based on in-band energy transfer of claim 4, wherein the target focused wave update operation is performed by reducing the overall energy of the target focused wave, specifically: Subtracting a constant from each wave height of each wave component when the wave height of each wave component of the target focused wave is determined based on the measured data and redefining the wave surface expression of the target focused wave, or redefining the wave surface expression of the target focused wave after performing an overall lowering operation on the energy spectrum constructing the target focused wave when the target focused wave is constructed based on the preset energy spectrum.
9. The method for generating a malformed wave based on in-band energy transfer according to claim 4, wherein the target focused wave updating operation is implemented by widening a focused frequency band, in particular: the current focusing frequency bands are respectively extended to two sides to obtain new focusing frequency bands, and then the wave surface expression of the target focusing wave is redetermined based on the new focusing frequency bands.
10. The method for generating an in-band energy transfer-based malformed wave according to claim 9, wherein, When the target focused wave updating operation is realized by widening the focused frequency band, both the energy contained by the first background wave and the target focused wave after the focused bandwidth is increased, and the energy increase amount of the first background wave is larger than that of the target focused wave.

Description

Abnormal wave generation method based on in-band energy transfer Technical Field The application belongs to the technical field of marine environment simulation, relates to wave numerical simulation and emulation technology, and particularly provides a method for generating a malformed wave based on in-band energy transfer. Background The abnormal wave (FREAK WAVES) is also called a monster wave (Rogue Waves), which refers to a wave with extremely large wave height suddenly appearing in the ocean, and has the characteristics of strong burst, abnormal wave height, short duration, difficult prediction and the like, and the wave height can reach 20-30 meters or even higher. The abnormal wave has extremely strong destructive power to offshore facilities such as ships, ocean platforms, offshore structures and the like, and along with the increasing of large ocean engineering such as deep sea oil gas exploitation, offshore wind farm construction, cross-sea bridge engineering and the like, the threat of the abnormal wave to offshore operation safety is increasingly outstanding, and the influence of the extreme wave is fully considered in the stages of ship design, ocean platform structure design and the like. The prior research mode of the malformation wave mainly comprises an actual observation mode, a pool experimental mode and a numerical simulation mode, wherein the actual observation mode is limited by the occurrence randomness and the small probability of the malformation wave, the cost for acquiring enough malformation wave data through actual observation is high, the period is long and is difficult to repeat, the experimental mode is that the malformation wave is actively generated in a pool through a wave making plate, the equipment scale, the manufacturing cost and the period are limited, the large-scale parameterization research is difficult to carry out, the numerical simulation mode is that the malformation wave which occurs at a specific position and at a specific time is directly generated in a numerical model of a limited volume water area, or the wave making plate model is driven to move according to preset wave making parameters in the numerical model of the pool, and the malformation wave which is generated at certain positions and times is obtained through numerical simulation of the movement and evolution of a fluid medium model, so that the pre-arranged data is provided for researching the influence of the malformation wave on ship movement response, the structural load, the platform stability and the like. The method is characterized in that abnormal wave data is generated by using a numerical simulation mode, so that key characteristics such as spectral characteristics, directional distribution, nonlinearity degree and the like of the abnormal wave under real sea conditions can be accurately reflected by the generated results, otherwise, large deviation exists between analysis results such as ship response, structural load and the like under the action of the abnormal wave and actual conditions. At present, various malformed wave generating methods exist, for example, patent CN120012433a proposes a malformed wave generating method based on a probability prediction model, and for example, patent CN114003847a discloses a malformed wave generating and modulating method and a spectrum correcting method. However, the above-mentioned existing methods do not consider the mutual conversion of energy in the process of generating and evolving the malformed wave, and lack significant physical constraints in the process of constructing and evolving the malformed wave, so that the generated malformed wave data is insufficient in physical rationality and reliability. Disclosure of Invention The application aims to provide a method for generating a malformed wave based on in-band energy transfer, which comprises the following steps: S1, determining a wave surface expression of a first background wave based on a target energy spectrum, wherein the energy density distribution of the first background wave in each frequency band is consistent with the target energy spectrum; S2, determining a wave surface expression of a target focused wave based on a wave-making target, wherein the wave-making target at least comprises a focusing moment, a focusing position, a focusing frequency band and wave heights of all wave components of the target focused wave; S3, if the energy of the first background wave in the focusing frequency band is larger than the energy of the target focusing wave in the focusing frequency band, carrying out in-band energy transfer operation on the first background wave under the total energy constraint of the focusing frequency band to generate a second background wave, otherwise, returning to the step S3 after the target energy spectrum lifting operation or the target focusing wave updating operation; s4, superposing the target focusing wave through the second background wave to generate a