Wave Motion最新文献_第7页

Elevating plasma physics: The role of higher-order nonlinearities in space dust shock waves with superthermal ions 提升等离子体物理：高阶非线性在具有过热离子的空间尘埃冲击波中的作用

IF 2.5 3区物理与天体物理 Q2 ACOUSTICS

Wave Motion

Pub Date : 2026-01-01 Epub Date: 2025-10-01 DOI: 10.1016/j.wavemoti.2025.103646

A. Atteya , Reem Altuijri , Kottakkaran Sooppy Nisar , Abdel-Haleem Abdel-Aty , M. Abd-Elzaher , Pralay Kumar Karmakar

This research explores the higher-order nonlinear and dissipative effects on dust acoustic shock waves in a complex plasma medium composed of inertial negative dust particles, Maxwellian electrons, and superthermal ions under the influence of polarization forces. Employing a perturbative approach, the research derives analytical descriptions of both first- and second-order potentials and electric fields, highlighting how these higher-order corrections significantly modify the shock wave structures. The analysis reveals that second-order potentials introduce negative contributions that reduce the overall wave amplitude, while the associated electric fields oppose the first-order fields, leading to self-regulating mechanisms that influence energy transport and wave stability. Numerical evaluations demonstrate how key plasma parameters, such as polarization strength, dust temperature, ion-to-electron density ratio, viscosity, and superthermality-affect phase velocity, nonlinearity, and shock profiles. The findings emphasize that including higher-order effects is crucial for accurately modeling shock dynamics in laboratory with direct relevance to astrophysical plasmas, notably the dynamics observed in planetary ring systems and cosmic dust environments, providing deeper insight into energy dissipation and wave evolution in complex dusty plasma systems.

本文研究了在由惯性负尘埃粒子、麦克斯韦电子和超热离子组成的复杂等离子体介质中，极化力对尘埃声激波的高阶非线性和耗散效应。采用微扰方法，该研究导出了一阶和二阶电位和电场的分析描述，强调了这些高阶修正如何显着改变激波结构。分析表明，二阶电位引入负贡献，降低了整体波幅，而相关电场与一阶电场相反，导致影响能量输运和波稳定性的自我调节机制。数值评估显示了关键的等离子体参数，如极化强度、尘埃温度、离子电子密度比、粘度和超热度，如何影响相速度、非线性和冲击剖面。研究结果强调，包括高阶效应对于准确模拟与天体物理等离子体直接相关的实验室冲击动力学至关重要，特别是在行星环系统和宇宙尘埃环境中观察到的动力学，为复杂尘埃等离子体系统的能量耗散和波演化提供了更深入的了解。

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引用次数: 0

Linear propagation of tsunami and acoustic–gravity waves on a sphere: Geometrical focusing and defocusing 海啸和声重力波在球体上的线性传播：几何聚焦和散焦

IF 2.5 3区物理与天体物理 Q2 ACOUSTICS

Wave Motion

Pub Date : 2026-01-01 Epub Date: 2025-10-10 DOI: 10.1016/j.wavemoti.2025.103643

Byron Williams , Ali Abdolali , Usama Kadri

This study investigates the propagation of tsunami and acoustic–gravity waves at oceanic scales, accounting for the Earth’s curvature within a linear, potential flow framework. While local, near-field analyses often neglect Earth’s curvature and employ Cartesian or cylindrical coordinate systems, this work utilises spherical coordinates to examine wave behaviour over large distances. The analysis reveals that wave amplitudes experience a defocusing effect as they travel from the source (e.g., the Pole) toward the equator, followed by a focusing effect as they approach the antipodal point beyond the equator. A qualitative comparison is made with the 2022 Hunga Tonga–Hunga Ha’apai volcanic eruption in the South Pacific. The study models surface-gravity (tsunami) waves propagating through a compressible water layer, as well as atmospheric acoustic–gravity waves propagating through the air. The entire analysis is carried out within the framework of linear theory.

本研究调查了海啸和声重力波在海洋尺度上的传播，在线性势流框架内考虑地球的曲率。虽然局部的近场分析经常忽略地球的曲率，并使用笛卡尔或柱坐标系，但这项工作利用球坐标来检查远距离上的波的行为。分析表明，当波幅从源（例如，极点）向赤道传播时，会经历散焦效应，随后当它们接近赤道以外的对映点时，会出现聚焦效应。并与2022年南太平洋Hunga Tonga-Hunga Ha 'apai火山喷发进行了定性比较。该研究模拟了通过可压缩水层传播的表面重力（海啸）波，以及通过空气传播的大气声重力波。整个分析是在线性理论的框架内进行的。

引用次数: 0

PT symmetry preserving, symmetry breaking and propagation behaviors in degenerate and non-degenerate solitons beyond the nonlocal Manakov system 非局部Manakov系统外简并和非简并孤子中的PT对称保持、对称破缺和传播行为

IF 2.1 3区物理与天体物理 Q2 ACOUSTICS

Wave Motion

Pub Date : 2025-11-01 Epub Date: 2025-06-25 DOI: 10.1016/j.wavemoti.2025.103593

Yang-Yang Du , Yan-Nan Zhao , Rui Guo , Jian-Wen Zhang

It is known that the four-wave mixing (FWM) not only serves as the basic paradigm for optical signal processing but can also result in the generation of more complex wave phenomena. In this paper, we investigate the properties of non-degenerate and degenerate solitons and their relevant collision dynamics for the generalized nonlocal Manakov system, which contains the FWM term. To start with, non-degenerate one-soliton solutions are derived by the Hirota’s bilinear method, and degenerate one- and two-soliton solutions (under specific restrictions on wave numbers) are also obtained in this way. Then, we illustrate the implications of the FWM for the humps of non-degenerate solitons briefly. To learn about the features of the nonlocalization, we obtain

P T

symmetry preserving and symmetry breaking soliton solutions, and identify stable and unstable propagations of soliton evolution for different modes. Given that the propagations of the mixed modes are stable, we investigate two discrepant types of collisions for degenerate two-soliton solutions, which are shown not to be conserved in energy for the individual solitons after the asymptotic analyses are constructed. This energy non-conservation characteristic of the collisions is in contrast to the nonlocal Manakov system, which is attributed to the FWM. Finally, taking into account the particularity of wave velocity, we also present the localized resonant pattern for different collisions.

众所周知，四波混频（FWM）不仅是光信号处理的基本范例，而且可以导致更复杂的波现象的产生。本文研究了包含FWM项的广义非局部Manakov系统的非简并孤子和简并孤子的性质及其相关的碰撞动力学。首先，利用Hirota的双线性方法推导了非简并单孤子解，并以此方法得到了简并单孤子解和简并单孤子解（在特定波数限制下）。然后，我们简要地说明了FWM对非简并孤子峰的影响。为了了解非局域化的特征，我们获得了PT对称保持和对称破缺孤子解，并识别了不同模式下孤子演化的稳定和不稳定传播。假设混合模的传播是稳定的，我们研究了简并双孤子解的两种不同类型的碰撞，在构造渐近分析后，证明了它们对单个孤子不守恒。这种碰撞的能量非守恒特性与归因于FWM的非局部Manakov系统相反。最后，考虑到波速的特殊性，给出了不同碰撞的局部共振模式。

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引用次数: 0

Mechanism investigations on certain unbounded/bounded breather molecules and transformed molecular waves for an extended (3+1)-dimensional Jimbo–Miwa equation in fluid mechanics 流体力学中扩展（3+1）维Jimbo-Miwa方程中某些无界/有界呼吸分子和转化分子波的机理研究

IF 2.1 3区物理与天体物理 Q2 ACOUSTICS

Wave Motion

Pub Date : 2025-11-01 Epub Date: 2025-07-23 DOI: 10.1016/j.wavemoti.2025.103608

Xuemin Yao , Jinjie Wen , Yuanhang Li , Junfei Zhao

In this paper, we present mechanistic investigations on certain bounded/unbounded breather molecules and transformed molecular wave formations through systematic analysis for an extended (3+1)-dimensional Jimbo–Miwa equation in fluid dynamics. Through characteristic lines analysis, we establish transformed wave solutions bifurcating from breather modes under critical state transition conditions. Such solutions demonstrate temporally evolving characteristics manifested as dynamic amplitude modulations and parametric waveform deformations. Moreover, we systematically investigate breather or transformed molecular wave complexes as collisionless structures, where the fundamental constituents are identified as individual breather waves and novel transformed wave counterparts. Unbounded or bounded molecular wave complexes, comprising identical or distinct constituent components, maintain fixed phase-locked separation distances while demonstrating propagation stability governed by nonlinear coupling constraints. These findings establish a potential theoretical framework for experimental studies in fluid dynamics, while also offering novel perspectives on the behavior of molecular waves in broader nonlinear physical systems.

本文通过对流体力学中扩展的（3+1）维Jimbo-Miwa方程的系统分析，对某些有界/无界呼吸分子和转化分子波的形成进行了力学研究。通过特征线分析，建立了临界状态跃迁条件下由呼吸模分岔的变换波解。这种解决方案表现出时间演化特征，表现为动态振幅调制和参数波形变形。此外，我们系统地研究了呼吸波或转化分子波复合物作为无碰撞结构，其中基本成分被确定为单个呼吸波和新的转化波对应体。由相同或不同组分组成的无界或有界分子波复合物保持固定的锁相分离距离，同时表现出非线性耦合约束下的传播稳定性。这些发现为流体动力学实验研究建立了一个潜在的理论框架，同时也为更广泛的非线性物理系统中的分子波行为提供了新的视角。

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引用次数: 0

Quasideterminant solutions for the Wadati–Konno–Ichikawa equation Wadati-Konno-Ichikawa方程的拟行列式解

IF 2.1 3区物理与天体物理 Q2 ACOUSTICS

Wave Motion

Pub Date : 2025-11-01 Epub Date: 2025-07-19 DOI: 10.1016/j.wavemoti.2025.103605

Halis Yilmaz

We employ a modified Darboux transformation to derive quasideterminant solutions for the modified Wadati–Konno–Ichikawa (mWKI) equation, an equivalent form of the WKI equation. As particular examples, we present multi-soliton solutions for both the focusing and defocusing cases using a zero seed solution. Additionally, we derive breather and rogue wave solutions of the mWKI equation starting from a non-zero seed solution.

我们利用一个修正的Darboux变换，导出了WKI方程的等价形式——修正wadati - kono - ichikawa （mWKI）方程的拟行列式解。作为特殊的例子，我们给出了使用零种子解的聚焦和散焦情况下的多孤子解。此外，我们从非零种子解出发，导出了mWKI方程的呼吸波解和突变波解。

引用次数: 0

In-plane linear stress waves in layered media: I. Non-Hermitian degeneracies and modal chirality 层状介质中的平面内线性应力波：1 .非厄米简并和模态手性

IF 2.5 3区物理与天体物理 Q2 ACOUSTICS

Wave Motion

Pub Date : 2025-11-01 Epub Date: 2025-08-05 DOI: 10.1016/j.wavemoti.2025.103610

Vahidreza Alizadeh, Alireza V. Amirkhizi

We study the band structure and scattering of in-plane coupled longitudinal and shear stress waves in linear layered media and observe that exceptional points (EP) appear for elastic (lossless) media, when parameterized with real-valued frequency and tangential wave vector component. The occurrence of these EP pairs is not limited to the original stop bands. They could also appear in all mode pass bands, leading to the formation of new stop bands. The scattered energy near these locations is studied along with the associated polarization patterns. The broken phase symmetry is observed inside the frequency bands book-ended by these EP pairs. This is especially manifested by the chirality of the trajectory of the particle velocity, which gets selected by a “direction” of the wave, e.g. the imaginary part of normal component of the wave vector, or the energy flux direction just outside the band. Additionally, EP pairs also appear in the spectrum of the (modified) scattering matrix when mechanical gain is theoretically included to balance the loss in a parity-time symmetric finite structure. These EP pairs lead to amplification of transmission to above 1 and single-sided reflectivity, both phenomena associated with broken phase symmetry, with intriguing potential applications.

我们研究了线性层状介质中面内耦合纵向和剪切应力波的带结构和散射，并观察到当用实值频率和切向波矢量分量参数化时，弹性（无损）介质中出现异常点（EP）。这些EP对的出现并不局限于原始的停止带。它们也可能出现在所有模式通带中，导致新的阻带的形成。研究了这些位置附近的散射能量以及相关的极化模式。在以这些极电位对为末端的频带内观察到相位对称性的破坏。这一点特别体现在粒子速度轨迹的手性上，它是由波的“方向”选择的，例如波矢量法向分量的虚部，或者带外的能量通量方向。此外，当理论上包括机械增益以平衡奇偶时间对称有限结构中的损耗时，EP对也出现在（修正的）散射矩阵的频谱中。这些电位对导致透射率放大到1以上和单面反射率，这两种现象都与相位对称性破坏有关，具有有趣的潜在应用前景。

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引用次数: 0

Eulerian contributions to the particle velocity in Stokes and Gerstner waves 欧拉对斯托克斯波和格斯纳波中粒子速度的贡献

IF 2.5 3区物理与天体物理 Q2 ACOUSTICS

Wave Motion

Pub Date : 2025-11-01 Epub Date: 2025-08-15 DOI: 10.1016/j.wavemoti.2025.103627

Jan Erik H. Weber

For inviscid periodic wave motion, we derive a novel expression in Lagrangian variables for the Stokes drift, which is valid for rotational as well as irrotational waves. The derivation confirms that the Lagrangian mean velocity can be expressed as the sum of the Eulerian mean velocity and the Stokes drift. However, from the Stokes drift part of this expression, we find that the rotational Gerstner wave has a non-zero Stokes drift. Since the Lagrangian mean velocity is zero for this particular wave, we obviously must have a non-zero Eulerian mean velocity in this case, cancelling the Stokes drift. To discuss this problem in detail, we return to the basic kinematics of periodic wave motion in fluids. We avoid time averaging and consider the classic problem of how the Lagrangian particle velocity develops in time, resulting in a Eulerian velocity (expressed in Lagrangian variables) plus the Stokes velocity. We discuss the implication for irrotational deep-water Stokes waves and rotational Gerstner waves. It is demonstrated that the Eulerian velocity, expressed in Lagrangian variables, is different for the two wave types. This explains why the Lagrangian mean velocity in the Stokes wave is equal to the Stokes drift, while it is zero for the Gerstner wave.

对于无粘周期波动，我们导出了一个新的斯托克斯漂移的拉格朗日变量表达式，该表达式适用于旋转波和无旋转波。推导证实了拉格朗日平均速度可以表示为欧拉平均速度和斯托克斯漂移之和。然而，从表达式的Stokes漂移部分，我们发现旋转Gerstner波具有非零Stokes漂移。由于这个波的拉格朗日平均速度为零，在这种情况下，我们显然必须有一个非零的欧拉平均速度，来抵消斯托克斯漂移。为了详细讨论这个问题，我们回到流体周期波动的基本运动学。我们避免时间平均，并考虑经典的拉格朗日粒子速度如何随时间发展的问题，导致欧拉速度（以拉格朗日变量表示）加上斯托克斯速度。讨论了非旋转深水Stokes波和旋转Gerstner波的含义。证明了用拉格朗日变量表示的欧拉速度对于两种波类型是不同的。这就解释了为什么斯托克斯波的拉格朗日平均速度等于斯托克斯漂移，而格斯纳波的拉格朗日平均速度为零。

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引用次数: 0

Acoustic axes conditions revised 修正的声轴条件

IF 2.1 3区物理与天体物理 Q2 ACOUSTICS

Wave Motion

Pub Date : 2025-11-01 Epub Date: 2025-07-07 DOI: 10.1016/j.wavemoti.2025.103602

Yakov Itin

The explanation of the basic acoustic properties of crystals requires a recognition of the acoustic axes. To derive the acoustic axes in a given material, one requires both a workable method and the necessary and sufficient criteria for the existence of the acoustic axes in a partial propagation direction. This paper’s primary input is an alternate minimal polynomial-based system of acoustic axes conditions. In this approach, we derive a novel additional characteristic of acoustic axes: the directions in which the minimal polynomial of the third order is reduced to that of the second order. Next, we offer a general solution, that utilizes a scalar and a unit vector for defining the acoustic tensor along the acoustic axis. It is shown that the scalar matches the eigenvalue of the reduced acoustic tensor, and the vector corresponds to the polarization into the single eigenvalue direction. We use the minimal polynomial construction to demonstrate the equivalence of different acoustic axis criteria. We demonstrate the applicability of this approach to actual computations of the acoustic axes and their fundamental properties (phase speeds and polarizations) for high symmetry cases, such as isotropic materials and RTHC crystals.

要解释晶体的基本声学特性，就必须认识声轴。为了推导给定材料中的声轴，既需要一种可行的方法，又需要在部分传播方向上存在声轴的必要和充分的准则。本文的主要输入是一个基于交替最小多项式的声轴条件系统。在这种方法中，我们导出了声轴的一个新的附加特征：三阶最小多项式降为二阶最小多项式的方向。接下来，我们提供了一个通用的解决方案，它利用一个标量和一个单位向量来定义沿着声学轴的声学张量。结果表明，标量与约简声张量的特征值相匹配，矢量对应于单特征值方向的极化。我们用最小多项式构造证明了不同声轴准则的等价性。我们证明了这种方法在高对称性情况下（如各向同性材料和RTHC晶体）声轴及其基本特性（相速度和极化）的实际计算中的适用性。

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引用次数: 0

Effect of horizontal and vertical components of initial stress on SH-wave propagation in a magneto-elastic fiber-reinforced (MEFR) layer 初始应力水平和垂直分量对磁弹性纤维增强（MEFR）层中sh波传播的影响

IF 2.1 3区物理与天体物理 Q2 ACOUSTICS

Wave Motion

Pub Date : 2025-11-01 Epub Date: 2025-07-21 DOI: 10.1016/j.wavemoti.2025.103607

Neetu Malik , Komal Gajroiya , Jitander Singh Sikka

This study aims to examine how the propagation of Shear Horizontal wave (SH-type waves) in a magneto-elastic fiber-reinforced (MEFR) layer with finite thickness is affected by initial stress. It rests upon a poroelastic transversely isotropic inhomogeneous half-space. The upper boundary of the layer is assumed to be rigid, and the layer and half-space are welded together. The displacement components of both the layer and half-space were derived and subsequently analyzed. The dispersion relation governing the propagation of SH-type waves was obtained and examined by applying appropriate boundary conditions for various scenarios. The confirmation of the mathematical model’s validity is evidenced by the simplification of the dispersion relation, which in turn streamlines the existing velocity wave equation for SH waves. The numerical computations were performed for distinct materials (steel and crystalline graphite) of the considered upper MEFR layer using the MATHEMATICA software, and the results were graphically presented. The dispersion curves provide insights into the impact of various parameters, including initial stress, magneto-elastic coupling, reinforcement, wave angle with respect to the magnetic field, heterogeneity of the half-space, porosity, and dynamic tortuosity, on wave propagation. Understanding the behavior of seismic waves can have significant practical implications for earthquake engineering and geophysics. Therefore, the findings of this study contribute to enhancing our knowledge of wave propagation, offering valuable insights for relevant fields.

本研究旨在研究有限厚度磁弹性纤维增强（MEFR）层中剪切水平波（sh型波）的传播如何受到初始应力的影响。它建立在孔隙弹性横向各向同性非均匀半空间上。假设层的上边界为刚性，层与半空间焊接在一起。推导了层和半空间的位移分量，并进行了分析。得到了控制sh型波传播的色散关系，并在不同情况下应用了适当的边界条件进行了检验。对频散关系的简化证明了数学模型的有效性，从而简化了现有的SH波速度波动方程。利用MATHEMATICA软件对MEFR上层的不同材料（钢和结晶石墨）进行了数值计算，并以图形形式给出了计算结果。色散曲线可以深入了解各种参数对波传播的影响，包括初始应力、磁弹性耦合、加固、相对于磁场的波角、半空间的非均质性、孔隙度和动态扭曲度。了解地震波的行为对地震工程和地球物理学具有重要的实际意义。因此，本研究的发现有助于提高我们对波传播的认识，为相关领域提供有价值的见解。

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引用次数: 0

Rayleigh wave dispersion and attenuation characterized by couple-stress-based poroelasticity 基于耦合应力的孔隙弹性瑞利波频散与衰减特征

IF 2.5 3区物理与天体物理 Q2 ACOUSTICS

Wave Motion

Pub Date : 2025-11-01 Epub Date: 2025-08-30 DOI: 10.1016/j.wavemoti.2025.103617

Guoqiang Li, Pei Zheng, Keming Zhang

In this paper, propagation of Rayleigh waves in a fluid-saturated porous solid is studied by using the couple-stress-based gradient theory, which incorporates the rotation gradient, and its work-conjugate counterpart, the couple-stress. In the frequency domain, wave equations involving a length parameter

ℓ

, that characterizes the microstructure of the material, are derived and, by using displacement potentials, coupled wave equations are reduced to four uncoupled wave equations governing the motions of

P_{1}

-,

P_{2}

-,

S V

-, and

S H

-waves. Based on the solutions of these equations, the dispersion equation for Rayleigh waves is obtained. Numerical results show that Rayleigh waves are dispersive at all frequencies in the range considered, unlike the velocity dispersion characterized by the classical theory, and the wave velocity is always higher than the conventional Rayleigh wave velocity. It is shown that the attenuation decreases as

ℓ

increases. The effects of porosity, the ratio of bulk modulus of the solid skeleton to the solid phase, and the length parameter on Rayleigh wave dispersion and attenuation are also investigated.

本文采用基于耦合应力的梯度理论研究了瑞利波在流体饱和多孔固体中的传播，该理论结合了旋转梯度和功共轭梯度，即耦合应力。在频域，导出了包含表征材料微观结构特征的长度参数的波动方程，并利用位移势将耦合波动方程简化为控制P1-， P2-， SV-和sh -波运动的四个不耦合波动方程。根据这些方程的解，得到了瑞利波的色散方程。数值结果表明，在考虑的范围内，瑞利波在所有频率上都是频散的，而不是经典理论所描述的速度频散，并且波速总是高于传统瑞利波速。结果表明，衰减随衰减系数的增大而减小。研究了孔隙率、骨架体积模量与固相之比以及长度参数对瑞利波色散和衰减的影响。

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引用次数: 0