{"title":"淹没杆阵的波散射:一种解析方法","authors":"P. Negi , T. Sahoo , V. Sriram , Y. Stepanyants","doi":"10.1016/j.wavemoti.2025.103645","DOIUrl":null,"url":null,"abstract":"<div><div>This paper provides a detailed analytic solution for examining the scattering of surface gravity waves by an array of bars. Depending on the incident wave period, bars are modelled as either trapezoidal or hump-shaped profiles. We formulate the problem as a boundary value problem governed by the mild-slope equation and employ the transfer matrix method to determine the scattering coefficients. Our analysis reveals that the number of bars and their spacing modulate Bragg resonance characteristics, with the number of sub-harmonic peaks between harmonic peaks being two fewer than the number of bars. For non-uniform bar arrays, rainbow reflection occurs, suppressing sub-harmonic peaks and eliminating multiple zeros in wave reflection. As the bar length approaches the water depth, wave diffraction becomes significant. Complete wave reflection by uniform bar arrays demonstrates a behaviour analogous to Fabry-Pérot resonance in optics. The Bragg reflection patterns exhibit distinctive properties: common zero minima for even numbers of bars and common maxima for odd numbers. When examining the inverse case — submerged trenches instead of bars — we observe similar harmonic and subharmonic components with consistent phase shifts and notably reduced reflected wave amplitudes. Wave field analysis demonstrates three distinct regions: standing waves on the incident side, progressive waves on the leeward side, and partly standing waves in the confined region between bars. The sloped geometries of the bar systems induce wave refraction and amplitude decay. Two-dimensional linear time-dependent surface elevations, simulated using a Gaussian pulse, capture the transient wave transformation dynamics throughout the submerged multi-bar systems.</div></div>","PeriodicalId":49367,"journal":{"name":"Wave Motion","volume":"140 ","pages":"Article 103645"},"PeriodicalIF":2.5000,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Wave scattering by an array of submerged bars: An analytic approach\",\"authors\":\"P. Negi , T. Sahoo , V. Sriram , Y. Stepanyants\",\"doi\":\"10.1016/j.wavemoti.2025.103645\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>This paper provides a detailed analytic solution for examining the scattering of surface gravity waves by an array of bars. Depending on the incident wave period, bars are modelled as either trapezoidal or hump-shaped profiles. We formulate the problem as a boundary value problem governed by the mild-slope equation and employ the transfer matrix method to determine the scattering coefficients. Our analysis reveals that the number of bars and their spacing modulate Bragg resonance characteristics, with the number of sub-harmonic peaks between harmonic peaks being two fewer than the number of bars. For non-uniform bar arrays, rainbow reflection occurs, suppressing sub-harmonic peaks and eliminating multiple zeros in wave reflection. As the bar length approaches the water depth, wave diffraction becomes significant. Complete wave reflection by uniform bar arrays demonstrates a behaviour analogous to Fabry-Pérot resonance in optics. The Bragg reflection patterns exhibit distinctive properties: common zero minima for even numbers of bars and common maxima for odd numbers. When examining the inverse case — submerged trenches instead of bars — we observe similar harmonic and subharmonic components with consistent phase shifts and notably reduced reflected wave amplitudes. Wave field analysis demonstrates three distinct regions: standing waves on the incident side, progressive waves on the leeward side, and partly standing waves in the confined region between bars. The sloped geometries of the bar systems induce wave refraction and amplitude decay. Two-dimensional linear time-dependent surface elevations, simulated using a Gaussian pulse, capture the transient wave transformation dynamics throughout the submerged multi-bar systems.</div></div>\",\"PeriodicalId\":49367,\"journal\":{\"name\":\"Wave Motion\",\"volume\":\"140 \",\"pages\":\"Article 103645\"},\"PeriodicalIF\":2.5000,\"publicationDate\":\"2025-09-30\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Wave Motion\",\"FirstCategoryId\":\"101\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0165212525001568\",\"RegionNum\":3,\"RegionCategory\":\"物理与天体物理\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"ACOUSTICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Wave Motion","FirstCategoryId":"101","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0165212525001568","RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ACOUSTICS","Score":null,"Total":0}
Wave scattering by an array of submerged bars: An analytic approach
This paper provides a detailed analytic solution for examining the scattering of surface gravity waves by an array of bars. Depending on the incident wave period, bars are modelled as either trapezoidal or hump-shaped profiles. We formulate the problem as a boundary value problem governed by the mild-slope equation and employ the transfer matrix method to determine the scattering coefficients. Our analysis reveals that the number of bars and their spacing modulate Bragg resonance characteristics, with the number of sub-harmonic peaks between harmonic peaks being two fewer than the number of bars. For non-uniform bar arrays, rainbow reflection occurs, suppressing sub-harmonic peaks and eliminating multiple zeros in wave reflection. As the bar length approaches the water depth, wave diffraction becomes significant. Complete wave reflection by uniform bar arrays demonstrates a behaviour analogous to Fabry-Pérot resonance in optics. The Bragg reflection patterns exhibit distinctive properties: common zero minima for even numbers of bars and common maxima for odd numbers. When examining the inverse case — submerged trenches instead of bars — we observe similar harmonic and subharmonic components with consistent phase shifts and notably reduced reflected wave amplitudes. Wave field analysis demonstrates three distinct regions: standing waves on the incident side, progressive waves on the leeward side, and partly standing waves in the confined region between bars. The sloped geometries of the bar systems induce wave refraction and amplitude decay. Two-dimensional linear time-dependent surface elevations, simulated using a Gaussian pulse, capture the transient wave transformation dynamics throughout the submerged multi-bar systems.
期刊介绍:
Wave Motion is devoted to the cross fertilization of ideas, and to stimulating interaction between workers in various research areas in which wave propagation phenomena play a dominant role. The description and analysis of wave propagation phenomena provides a unifying thread connecting diverse areas of engineering and the physical sciences such as acoustics, optics, geophysics, seismology, electromagnetic theory, solid and fluid mechanics.
The journal publishes papers on analytical, numerical and experimental methods. Papers that address fundamentally new topics in wave phenomena or develop wave propagation methods for solving direct and inverse problems are of interest to the journal.