Wave MotionPub Date : 2024-10-28DOI: 10.1016/j.wavemoti.2024.103429
P.A. Martin
{"title":"On peridynamic acoustics","authors":"P.A. Martin","doi":"10.1016/j.wavemoti.2024.103429","DOIUrl":"10.1016/j.wavemoti.2024.103429","url":null,"abstract":"<div><div>We consider a nonlocal (peridynamic) version of the classical forced wave equation. This scalar three-dimensional equation contains a weight function (the “micromodulus”) and a length parameter (the “horizon”) that have to be selected. We investigate various properties (the locality limit as the horizon shrinks, plane waves and group velocity), paying attention to how these properties depend on the choice of the micromodulus. We solve the forced peridynamic equation in the static case (avoiding divergent integrals) and in the time-harmonic case (with a radiation condition, when needed).</div></div>","PeriodicalId":49367,"journal":{"name":"Wave Motion","volume":"132 ","pages":"Article 103429"},"PeriodicalIF":2.1,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142572507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Wave MotionPub Date : 2024-10-28DOI: 10.1016/j.wavemoti.2024.103430
Alverède Simon, Tony Valier-Brasier, Jean-Marc Conoir
{"title":"Elastic coupled phase theory based on the Cosserat equations: Propagation of coherent waves","authors":"Alverède Simon, Tony Valier-Brasier, Jean-Marc Conoir","doi":"10.1016/j.wavemoti.2024.103430","DOIUrl":"10.1016/j.wavemoti.2024.103430","url":null,"abstract":"<div><div>We develop a new coupled phase theory (CPT) in order to model the propagation of elastic coherent waves in homogeneous solid media containing randomly distributed spherical elastic inclusions. To this end, the Buyevich’s theory previously developed for fluid media (Buyevich and Shchelchkova, 1978) has been adapted and applied to the Cosserat equations. A key point is to introduce the Independent Scattering Approximation (ISA). We show that the coherent wavenumbers depend explicitly on the external force applied to spheres, the torque characterizing their rotation and the stresslet which is the result of the resistance of the particles to the straining motion. Numerical results are in good agreement with experimental data.</div></div>","PeriodicalId":49367,"journal":{"name":"Wave Motion","volume":"132 ","pages":"Article 103430"},"PeriodicalIF":2.1,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142578004","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Wave MotionPub Date : 2024-10-24DOI: 10.1016/j.wavemoti.2024.103425
Xiaodong Liu , Jiguang Sun , Lei Zhang
{"title":"Accurate computation of scattering poles of acoustic obstacles with impedance boundary conditions","authors":"Xiaodong Liu , Jiguang Sun , Lei Zhang","doi":"10.1016/j.wavemoti.2024.103425","DOIUrl":"10.1016/j.wavemoti.2024.103425","url":null,"abstract":"<div><div>We propose a computation method for scattering poles of impedance obstacles. Boundary integral equations are used to formulate the problem. It is shown that the scattering poles are the eigenvalues of some integral operator. Then we employ the Nyström method to discretize the integral operator and obtain a nonlinear matrix eigenvalue problem. The eigenvalues are computed using a multistep parallel spectral indicator method. Numerical examples demonstrate the high accuracy of the proposed method and can serve as the benchmarks. Our study provides a practical approach and can be extended to other scattering problems. This paper continues our previous study on the computation method for scattering poles of sound-soft obstacles.</div></div>","PeriodicalId":49367,"journal":{"name":"Wave Motion","volume":"132 ","pages":"Article 103425"},"PeriodicalIF":2.1,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142552651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Wave MotionPub Date : 2024-10-22DOI: 10.1016/j.wavemoti.2024.103423
Xinru Guo, Wentao Li, Biao Li
{"title":"Derivation of weakly interacting lumps for the (2+1)-dimensional Yu–Toda–Sasa–Fukuyama equation via degeneracy of lump chains","authors":"Xinru Guo, Wentao Li, Biao Li","doi":"10.1016/j.wavemoti.2024.103423","DOIUrl":"10.1016/j.wavemoti.2024.103423","url":null,"abstract":"<div><div>This paper introduces two distinct pathways for degenerating normally interacting lump chains into weakly interacting lump waves for Yu–Toda–Sasa–Fukuyama equation, which will enrich the correlation between lump chains and weakly interacting lump waves. The first pathway involves letting the periods of <span><math><mi>M</mi></math></span> similarly-velocity lump chains approach infinity directly. The second pathway first transforms <span><math><mi>M</mi></math></span> normally interacting lump chains into weakly interacting lump chains with similar dynamic behaviors. Then, by allowing their periods to approach infinity, <span><math><mfrac><mrow><mi>M</mi><mfenced><mrow><mi>M</mi><mo>+</mo><mn>1</mn></mrow></mfenced></mrow><mrow><mn>2</mn></mrow></mfrac></math></span> weakly interacting lump waves are produced. Distance between weakly interacting lump chains in this equation is proportional to <span><math><mrow><mo>ln</mo><mo>|</mo><mi>t</mi><mo>|</mo></mrow></math></span>, while between weakly interacting lump waves is proportional to <span><math><mroot><mrow><mo>|</mo><mi>t</mi><mo>|</mo></mrow><mrow><mn>3</mn></mrow></mroot></math></span>. These findings will contribute valuable theoretical insights to the study of wave theory, ocean science and related disciplines.</div></div>","PeriodicalId":49367,"journal":{"name":"Wave Motion","volume":"132 ","pages":"Article 103423"},"PeriodicalIF":2.1,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142552650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Wave MotionPub Date : 2024-10-22DOI: 10.1016/j.wavemoti.2024.103427
Philip Rosenau , Alexander Oron
{"title":"Compactons in a class of doubly sublinear Gardner equations","authors":"Philip Rosenau , Alexander Oron","doi":"10.1016/j.wavemoti.2024.103427","DOIUrl":"10.1016/j.wavemoti.2024.103427","url":null,"abstract":"<div><div>We introduce and study a class of doubly sublinear Gardner equations <span><math><mrow><msub><mrow><mi>u</mi></mrow><mrow><mi>t</mi></mrow></msub><mo>+</mo><mi>F</mi><msub><mrow><mrow><mo>(</mo><mi>u</mi><mo>;</mo><mi>n</mi><mo>)</mo></mrow></mrow><mrow><mi>x</mi></mrow></msub><mo>+</mo><msub><mrow><mi>u</mi></mrow><mrow><mn>3</mn><mi>x</mi></mrow></msub><mo>=</mo><mn>0</mn></mrow></math></span> where <span><math><mrow><mi>F</mi><mrow><mo>(</mo><mi>u</mi><mo>;</mo><mi>n</mi><mo>)</mo></mrow><mo>=</mo><msup><mrow><mi>u</mi></mrow><mrow><mn>1</mn><mo>+</mo><mi>n</mi></mrow></msup><mo>−</mo><msub><mrow><mi>κ</mi></mrow><mrow><mn>1</mn><mo>+</mo><mn>2</mn><mi>n</mi></mrow></msub><msup><mrow><mi>u</mi></mrow><mrow><mn>1</mn><mo>+</mo><mn>2</mn><mi>n</mi></mrow></msup></mrow></math></span>, which for <span><math><mrow><mn>0</mn><mo><</mo><mi>n</mi></mrow></math></span> induce solitons and in the doubly sublinear cases wherein <span><math><mrow><mo>−</mo><mn>1</mn><mo>/</mo><mn>2</mn><mo><</mo><mi>n</mi><mo><</mo><mn>0</mn></mrow></math></span>, <em>bi-directional</em> compactons propagating in either direction. Their emergence, evolution, chase and head-on interactions are studied.</div></div>","PeriodicalId":49367,"journal":{"name":"Wave Motion","volume":"132 ","pages":"Article 103427"},"PeriodicalIF":2.1,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142531508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Wave MotionPub Date : 2024-10-22DOI: 10.1016/j.wavemoti.2024.103424
José M. Carcione , Jing Ba
{"title":"Test of the relation between temporal and spatial Q by Knopoff et al.","authors":"José M. Carcione , Jing Ba","doi":"10.1016/j.wavemoti.2024.103424","DOIUrl":"10.1016/j.wavemoti.2024.103424","url":null,"abstract":"<div><div>The quality factor is a dimensionless measure of the energy loss per cycle of wave modes in an attenuation medium. Accurate measurement is important in various fields, from seismological studies to detect zones of partial melting to the geophysics of reservoirs to study rock properties such as porosity, fluid properties and saturation and permeability. In seismology, the quality factors measured for normal (standing) modes and propagating waves differ, as well those of equivalent experiments based on resonant rods and ultrasonic pulses performed in the laboratory. These measurements result in temporal and spatial quality factors respectively. A relationship between these two different quality factors and between the corresponding attenuation factors was proposed by Knopoff et al. sixty years ago. The conversion factor is basically the ratio between the phase velocity and the group velocity, while for the attenuation factor is the group velocity. We test these relations, which hold for low-loss solids, for body waves, using a Kelvin–Voigt rheology and a constant <span><math><mi>Q</mi></math></span> model, which provide explicit expressions of the temporal and spatial quality factors and velocities involved in these relations. The proposed theory provides the basis for a complete characterization of temporal and spatial quality factors and velocity dispersion based on arbitrary stress–strain relationships.</div></div>","PeriodicalId":49367,"journal":{"name":"Wave Motion","volume":"132 ","pages":"Article 103424"},"PeriodicalIF":2.1,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142552652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Wave MotionPub Date : 2024-10-22DOI: 10.1016/j.wavemoti.2024.103426
Liu Yang, Ben Gao
{"title":"The dynamic behaviors between double-hump solitons in birefringent fibers","authors":"Liu Yang, Ben Gao","doi":"10.1016/j.wavemoti.2024.103426","DOIUrl":"10.1016/j.wavemoti.2024.103426","url":null,"abstract":"<div><div>In this paper, we research the fractional coupled Hirota equations with variable coefficients describing the collisions of two waves in deep oceans and the propagation of ultrashort light pulses in birefringent fibers and successfully acquire the double-hump one-soliton, two-solitons and <em>N</em>-solitons solutions via the Hirota bilinear method. At the same time, the Bäcklund transformation and the corresponding soliton solutions are also obtained. Based on the precise forms of the solitons solutions, we gain double-hump solitons images with different shapes including U-shape, V-shape and wave-type by assigning proper functions to the group velocity dispersion and the third-order dispersion and analyze the interaction dynamics of double-hump solitons. It is worth noting that the Hirota bilinear operators involved here are fractional rather than integer, which has never appeared in previous literatures.</div></div>","PeriodicalId":49367,"journal":{"name":"Wave Motion","volume":"132 ","pages":"Article 103426"},"PeriodicalIF":2.1,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142531507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Wave MotionPub Date : 2024-10-19DOI: 10.1016/j.wavemoti.2024.103418
John Lekner
{"title":"Localized solutions of the wave equation","authors":"John Lekner","doi":"10.1016/j.wavemoti.2024.103418","DOIUrl":"10.1016/j.wavemoti.2024.103418","url":null,"abstract":"<div><div>A family of solutions of the wave equation is presented. The simplest waveforms represent sub-cycle pulses; oscillatory pulses with a dominant wavenumber are also discussed. These solutions are sufficiently localized to have finite energy, momentum, and angular momentum when applied to acoustic and electromagnetic pulses. The energy, momentum, and angular momentum of the pulses are simply expressed in terms of the wavenumber weight function.</div></div>","PeriodicalId":49367,"journal":{"name":"Wave Motion","volume":"132 ","pages":"Article 103418"},"PeriodicalIF":2.1,"publicationDate":"2024-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142578003","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Wave MotionPub Date : 2024-10-19DOI: 10.1016/j.wavemoti.2024.103431
Ting Wang , Huachang Cui , Jingyu Zhang , Hanbei Guo , Meixia Chen
{"title":"Longitudinal wave propagation in a practical metamaterial lattice","authors":"Ting Wang , Huachang Cui , Jingyu Zhang , Hanbei Guo , Meixia Chen","doi":"10.1016/j.wavemoti.2024.103431","DOIUrl":"10.1016/j.wavemoti.2024.103431","url":null,"abstract":"<div><div>A practical metamaterial lattice is constructed by integrating curved beams, four-link mechanisms, and cantilever beams with lumped masses. It can generate two complete low-frequency bandgaps due to the lateral local resonance, inertia mass, and the main chain. The effective mass density and stiffness are obtained using different effective models, which show negative within the bandgaps. The analysis of the energy distribution and the space wave attenuation reveals that the metamaterial can attenuate the elastic waves in an exponential form within the bandgaps along the lattice. The finite element model is established to show the dynamic behaviour of the elastic wave propagation in the frequency domain and transient domain. Both results show that waves can be efficiently blocked within the bandgaps, while outside the bandgaps, waves can propagate without any attenuation. Finally, the experimental model of practical metamaterial is constructed, and the test piece is excited by a force hammer. Experimental results verify that the practical metamaterial can efficiently suppress the vibration within the bandgap frequency and validate the accuracy of the theoretical prediction.</div></div>","PeriodicalId":49367,"journal":{"name":"Wave Motion","volume":"132 ","pages":"Article 103431"},"PeriodicalIF":2.1,"publicationDate":"2024-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142593082","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Wave MotionPub Date : 2024-10-16DOI: 10.1016/j.wavemoti.2024.103422
Didier Felbacq, Anthony Gourdin, Emmanuel Rousseau
{"title":"A single layer representation of the scattered field for multiple scattering problems","authors":"Didier Felbacq, Anthony Gourdin, Emmanuel Rousseau","doi":"10.1016/j.wavemoti.2024.103422","DOIUrl":"10.1016/j.wavemoti.2024.103422","url":null,"abstract":"<div><div>The scattering of scalar waves by a set of scatterers is considered. It is proven that the scattered field can be represented as an integral supported by any smooth surface enclosing the scatterers. This is a generalization of the series expansion over spherical harmonics and spherical Bessel functions for spherical geometries. More precisely, given a set of scatterers, the field scattered by any subset can be expressed as an integral over any smooth surface enclosing the given subset alone. It is then possible to solve the multiple scattering problem by using this integral representation instead of an expansion over spherical harmonics. This result is used to develop an extension of the Fast Multipole Method in order to deal with subsets that are not enclosed within non-intersecting balls.</div></div>","PeriodicalId":49367,"journal":{"name":"Wave Motion","volume":"132 ","pages":"Article 103422"},"PeriodicalIF":2.1,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142531506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}