Short-term forecasting method and application of abnormal wave based on wave group characteristics in two-dimensional sea state

Abstract

The invention provides a short-term forecast method and application of deformed waves based on wave group characteristics under two-dimensional sea conditions, belonging to the field of ships and ocean engineering. In order to solve the problem of accurate and fast prediction of deformed waves, the key points are step 1: obtain real-time measured ocean wave sequences; step 2: identify and divide wave groups in the measured ocean wave sequences based on wavelet transform; step 3: use independent wave The instantaneous frequency of the group and the BFI value of the wave group satisfy certain conditions as the prerequisite for the occurrence of deformed waves, and then quickly calculate the evolution of the wave group by combining wave theory and nonlinear Schrödinger equation simulation, and finally judge whether a deformed wave occurs, the effect The present invention uses wavelet transform to process the wave surface information, so as to separate each wave group well, and then quickly calculates the evolution of the wave group through the combination of wave theory and nonlinear Schrödinger equation simulation, so as to judge whether the deformed wave is occur.

Description

technical field [0001] The invention belongs to the field of ships and ocean engineering, and relates to a method for avoiding sudden catastrophic sea waves for ships and ocean engineering. Background technique [0002] Wave is the most important dynamic load in ocean engineering, which plays a decisive role in the design and safe operation of ocean structures. In the actual marine environment, the deformed wave is a sudden catastrophic wave in the ocean. Operation and safety pose a threat, and even lead to the capsizing of ships and damage to marine structures such as offshore platforms, causing heavy casualties and economic losses. According to research, there are a large number of marine accidents caused by deformed waves every year. Therefore, how to predict deformed waves is a common goal pursued by the ship and ocean engineering industry and the scientific community. However, due to the late start of the research on freak waves and the complex generation mechanism, ...

AI Technical Summary

Problems solved by technology

In the traditional wave group identification method, the wave group is often determined by the continuous wave height of the wave train exceeding a certain threshold, which not only has certain human factors, but also cannot be accurately identified

At present, the main mechanism of deformed wave generation is: on the one hand, due to the dispersion focusing of waves, that is, the linear superposition of each wave component in the wave group evolution generates a deformed wave; on the other hand, due to the instability of wave modulation in the wave group evolution, that is, the carrier and edge When the band wave numbers are similar, the nonlinear effect causes the carrier wave to be affected by the disturbance sideband wave, and the amplitude of the wave train increases exponentially to produce a deformed wave

Images