文献类型：期刊文献

英文题名：Experimental investigation on the frequency characteristics of freak waves over a submerged breakwater by Variational Mode Decomposition

作者：He, Yanli[1,2];Wang, Suijun[1];Lin, Jinbo[1];Chen, Hongzhou[2,3];Dong, Guohai[2]

机构：[1]Guangdong Ocean Univ, Coll Ocean Engn & Energy, Zhanjiang 524088, Peoples R China;[2]Dalian Univ Technol, State Key Lab Coastal & Offshore Engn, Dalian 116024, Peoples R China;[3]Zhejiang Ocean Univ, Sch Marine Engn Equipment, Zhoushan 316022, Peoples R China

年份：2025

卷号：342

外文期刊名：OCEAN ENGINEERING

收录：SCI-EXPANDED(收录号：WOS:001579642500004)、、EI(收录号：20254119286011)、Scopus(收录号：2-s2.0-105017853722)、WOS

基金：This work is supported by the Guangdong Basic and Applied Basic Research Foundation (grant number 2024A1515012321) , the Special Fund Competition Allocation Project of Guangdong Science and Tech-nology Innovation Strategy (grant number 2023A01022) , the Open Fund of State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology (grant number LP2403) .

语种：英文

外文关键词：Nonlinear parameter; Instantaneous frequency; Freak waves; Variational Mode Decomposition

外文摘要：This study experimentally investigates the propagation and evolution dynamics of random waves over a submerged breakwater. The results demonstrate that rapid water depth variations significantly enhance the probability of freak wave occurrence, with the seaward slope termination and breakwater crest emerging as primary hotspots for these extreme events. Instantaneous frequency analysis effectively captures the nonlinear wave characteristics induced by depth reduction, with sharp increase in higher-mode instantaneous frequencies clearly indicating energy transfer to high-frequency components during freak wave generation. Crucially, the study reveals strong correlations between instantaneous frequencies and key hydrodynamic nonlinear parameters: the dimensionless instantaneous frequencies (normalized by component-specific dominant frequencies) closely track the variations of nonlinearity index (epsilon) and Ursell number (Ur), while showing minimal sensitivity to dispersion effects. These findings confirm intra-wave frequency modulation as a robust diagnostic tool for depth-induced nonlinear wave transformations, which provides novel analytical perspectives for characterizing freak wave dynamics and their generation mechanisms.