Wave Propagation in Dissipative Or Dispersive Nonlinear Media

Wave Propagation in Dissipative Or Dispersive Nonlinear Media PDF Author: Mevlüt Teymur
Publisher:
ISBN:
Category : Differential equations, Partial
Languages : en
Pages : 182

Get Book Here

Book Description

Wave Propagation in Dissipative Or Dispersive Nonlinear Media

Wave Propagation in Dissipative Or Dispersive Nonlinear Media PDF Author: Mevlüt Teymur
Publisher:
ISBN:
Category : Differential equations, Partial
Languages : en
Pages : 182

Get Book Here

Book Description


The Propagation of Disturbances in Dispersive Media

The Propagation of Disturbances in Dispersive Media PDF Author: Sir Thomas Havelock
Publisher:
ISBN:
Category : Mathematical physics
Languages : en
Pages : 100

Get Book Here

Book Description
The present tract deals with the manner in which a limited initial disturbance spreads out into a dispersive medium and with allied problems - p. 1.

Phase-space Analysis of Wave Propagation in Homogeneous Dispersive and Dissipative Media

Phase-space Analysis of Wave Propagation in Homogeneous Dispersive and Dissipative Media PDF Author: Ngo Dinh Hoc
Publisher:
ISBN:
Category : Radio wave propagation
Languages : en
Pages : 510

Get Book Here

Book Description


Nonlinear Waves in Active Media

Nonlinear Waves in Active Media PDF Author: Jüri Engelbrecht
Publisher: Springer Science & Business Media
ISBN: 3642747892
Category : Science
Languages : en
Pages : 284

Get Book Here

Book Description
TIlis volume contains the contributions to the Euromech Colloquium No. 241 on Nonlinear Waves in Active Media at the Institute of Cybernetics of the Estonian Academy of Sciences, Tallinn, Estonia, USSR, September 27-30, 1988. The Co-chairmen of the Euromech Colloquium felt that it would be a good service to the community to publish these proceedings. First, the topic itself dealing with various wave processes with energy influx is extremely interesting and attracted a much larger number of participants than usual - a clear sign of its importance to the scientific community. Second, Euromech No. 241 was actually the first Euromech Colloquium held in the Soviet Union and could thus be viewed as a milestone in the extending scientific contacts between East and West. At the colloquium 50 researchers working in very different branches of sci ence met to lecture on their results and to discuss problems of common interest. An introductory paper by I. Engelbrecht presents the common motivation and background of the topics covered. Altogether 36 speakers presented their lectures, of which 30 are gathered here. The remaining six papers which will appear elsewhere are listed on page X. In addition, three contributions by authors who could not attend the colloquium are included. The two lectures given by A.S. Mikhailov, V.S. Davydov and V.S. Zykov are here published as one long paper.

Selected Topics in Nonlinear Wave Mechanics

Selected Topics in Nonlinear Wave Mechanics PDF Author: C.I. Christov
Publisher: Springer Science & Business Media
ISBN: 1461200954
Category : Mathematics
Languages : en
Pages : 274

Get Book Here

Book Description
This book gives an overview ofthe current state of nonlinear wave mechanics with emphasis on strong discontinuities (shock waves) and localized self preserving shapes (solitons) in both elastic and fluid media. The exposition is intentionallyat a detailed mathematical and physical level, our expectation being that the reader will enjoy coming to grips in a concrete manner with advances in this fascinating subject. Historically, modern research in nonlinear wave mechanics began with the famous 1858 piston problem paper of Riemann on shock waves and con tinued into the early part of the last century with the work of Hadamard, Rankine, and Hugoniot. After WWII, research into nonlinear propagation of dispersive waves rapidly accelerated with the advent of computers. Works of particular importance in the immediate post-war years include those of von Neumann, Fermi, and Lax. Later, additional contributions were made by Lighthill, Glimm, Strauss, Wendroff, and Bishop. Dispersion alone leads to shock fronts of the propagating waves. That the nonlinearity can com pensate for the dispersion, leading to propagation with a stable wave having constant velocity and shape (solitons) came as a surprise. A solitary wave was first discussed by J. Scott Russell in 1845 in "Report of British Asso ciations for the Advancement of Science. " He had, while horseback riding, observed a solitary wave travelling along a water channel and followed its unbroken progress for over a mile.

Non-Linear Waves in Dispersive Media

Non-Linear Waves in Dispersive Media PDF Author: V. I. Karpman
Publisher: Elsevier
ISBN: 1483187152
Category : Science
Languages : en
Pages : 199

Get Book Here

Book Description
Non-Linear Waves in Dispersive Media introduces the theory behind such topic as the gravitational waves on water surfaces. Some limiting cases of the theory, wherein proof of an asymptotic class is necessary and generated, are also provided. The first section of the book discusses the notion of linear approximation. This discussion is followed by some samples of dispersive media. Examples of stationary waves are also examined. The book proceeds with a discussion of waves of envelopes. The concept behind this subject is from the application of the methods of geometrical optics to non-linear theory. A section on non-linear waves with slowly varying parameters is given at the end of the book, along with a discussion of the evolution of electro-acoustic waves in plasma with negative dielectric permittivity. The gravitational waves on fluid surfaces are presented completely. The text will provide valuable information for physicists, mechanical engineers, students, and researchers in the field of optics, acoustics, and hydrodynamics.

Wave Processes in Solids with Microstructure

Wave Processes in Solids with Microstructure PDF Author: Vladimir I. Erofeyev
Publisher: World Scientific
ISBN: 9789812794505
Category : Science
Languages : en
Pages : 282

Get Book Here

Book Description
1. The fundamental hypothesis of microstructured elastic solids. Structural-phenomenological model. 1.1. Mathematical models of solids with microstructure. 1.2. Definition of material constants -- 2. Gradient elasticity media. Dispersion. Dissipation. Non-linearity. 2.1. Dynamic equations. Energy and momentum variation law. 2.2. Dispersion properties of longitudinal and shear waves. Surface Rayleigh waves. 2.3. Dissipative properties. 2.4. Nonlinear plain stationary waves. 2.5. Quasi-plain wave beams. 2.6. Self-modulation of quasi-harmonic shear waves. 2.7. Resonant interaction of quasi-harmonic waves. 2.8. Noise waves -- 3. Gradient elasticity media. Damaged medium. Magnetoelasticity. 3.1. Waves in damaged medium with microstructure. 3.2. Magneto-elastic waves in the medium with microstructure -- 4. Cosserat continuum. 4.1. Basic equations of micropolar elasticity theory. 4.2. Dispersion properties of volume waves. 4.3. Wave reflection from the free interface of micropolar halfspace. Rayleigh surface waves. 4.4. Normal waves in a micropolar layer. 4.5. Nonlinear resonant interaction of longitudinal and rotation waves. 4.6. Waves in Cosserat pseudocontinuum. 4.7. Waves in the Cosserat continuum with symmetric stress tensor -- 5. Waves in two-component mixture of solids. 5.1. Dispersion properties. 5.2. Some nonlinear wave effects -- 6. Waves in micromorphic solids. 6.1. Dynamics equations. 6.2. Different types of volume waves and their dispersion properties. 6.3. Surface shear waves in the gradient-elastic half-space with surface energy -- 7. Elasto-plastic waves in the medium with dislocations. 7.1. Equations of dynamics. 7.2. Dispersion properties. 7.3. Some nonlinear problems. 7.4. Correlation of elasto-plastic continuum and Cosserat continuum. 7.5. Example of research of the influence of dislocations on dispersion and damping of ultrasound in solid body -- 8. Wave problems of micropolar hydrodynamics. 8.1. Rotational waves in micropolar liquids. 8.2. Shear surface wave at the interface of elastic body and micropolar liquid. 8.3. Shear surface wave at the interface between elastic half-space and conducting viscous liquid in a magnetic field.

Wave Propagation in Linear and Nonlinear Periodic Media

Wave Propagation in Linear and Nonlinear Periodic Media PDF Author: Francesco Romeo
Publisher: Springer Science & Business Media
ISBN: 3709113091
Category : Technology & Engineering
Languages : en
Pages : 332

Get Book Here

Book Description
Waves and defect modes in structures media.- Piezoelectric superlattices and shunted periodic arrays as tunable periodic structures and metamaterials.- Topology optimization.- Map-based approaches for periodic structures.- Methodologies for nonlinear periodic media.​ The contributions in this volume present both the theoretical background and an overview of the state-of-the art in wave propagation in linear and nonlinear periodic media in a consistent format. They combine the material issued from a variety of engineering applications, spanning a wide range of length scale, characterized by structures and materials, both man-made and naturally occurring, featuring geometry, micro-structural and/or materials properties that vary periodically in space, including periodically stiffened plates, shells and beam-like as well as bladed disc assemblies, phononic metamaterials, photonic crystals and ordered granular media. Along with linear models and applications, analytical methodologies for analyzing and exploiting complex dynamical phenomena arising in nonlinear periodic systems are also presented.​

Ray Methods for Nonlinear Waves in Fluids and Plasmas

Ray Methods for Nonlinear Waves in Fluids and Plasmas PDF Author: Marcelo Anile
Publisher: CRC Press
ISBN: 1000444856
Category : Mathematics
Languages : en
Pages : 255

Get Book Here

Book Description
Presents in a systematic and unified manner the ray method, in its various forms, for studying nonlinear wave propagation in situations of physical interest, essentially fluid dynamics and plasma physics.

Nonlinear Wave Propagation in Non-Hermitian Media

Nonlinear Wave Propagation in Non-Hermitian Media PDF Author: Sathyanarayanan Chandramouli
Publisher:
ISBN:
Category : Mathematics
Languages : en
Pages : 0

Get Book Here

Book Description
In this thesis, we develop and study two distinct problems in the field of nonlinear waves. The first part of the thesis is connected to the development of a computational algorithm that preserves underlying structure of the simulated initial boundary value problem in the form of multiple global conservation laws or dissipation rate equations. \\\\begin{itemize}\\\\item The time-dependent spectral renormalization (TDSR) method was introduced by Cole and Musslimani as a viable method to numerically solve initial boundary value problems. An important and novel aspect of the TDSR scheme is its ability to incorporate physics in the form of conservation laws or dissipation rate equations. However, the method was restricted to enforce the conservation or dissipation rate of just one quantity. The present work significantly extends the computational features of the algorithm with the (i) incorporation of multiple conservation laws and/or dissipation rate equations, (ii) ability to enforce versatile boundary conditions, and (iii) higher-order time integration strategies. The TDSR method is applied on several prototypical evolution equations of physical significance. Examples include the Korteweg-de Vries (KdV), multi-dimensional nonlinear Schr\\\\"odinger (NLS) and the Allen-Cahn equations. The work was published in Nonlinearity \\\\cite{chandramouli2022time}. \\\\end{itemize} The second half of the thesis identifies a broad class of novel, \\\\textit{non-centered} Riemann problems in optical media with externally imposed gain and loss distributions. Thereafter, we shed light on some unique features that arise from step-like distributions in such spatially inhomogeneous media. Our work thus is an important contribution to the field of non-Hermitian dispersive hydrodynamics. \\\\begin{itemize} \\\\item Dispersive hydrodynamics, the study of nonlinear dispersive wave dynamics in fluid-like media, is an active research area that combines mathematical analysis with computational and laboratory experiments. To date, most of the research in this area has been focused on wave phenomena in (i) bulk media, in which case the underlying governing equations are of constant coefficients type, or (ii) inhomogeneous environments, where now the evolution equations contain, for example, a real-valued external potential. In the latter case, the presence of inhomogeneity (in general) hinders the formulation of a Riemann problem due to the lack of plane wave-type solutions of constant intensity (or density). However such waves can exist in non-Hermitian media, as was demonstrated for the nonlinear Schrödinger (NLS) equation with a Wadati-type complex external potential. Inspired by the above-mentioned discussions, in this paper, the notion of non-Hermitian dispersive hydrodynamics and its associated non-Hermitian Riemann problems are introduced. Starting from the defocusing (repulsive) NLS equation in the presence of generic smooth complex external potentials, a new set of hydrodynamic-like equations are obtained. They differ from their classical counterparts (without an external potential), by the presence of additional source terms that alter the density and momentum equations. When restricted to a class of Wadati-type complex potentials, this new non-Hermitian hydrodynamic system admits constant intensity/density solutions. This in turn, allows one to formulate an exact centered (or non-centered) Riemann problem involving a step-like initial condition that connects two exact constant density states. A broad class of non-Hermitian potentials that lead to modulationally stable constant intensity states are identified. These results are subsequently used to numerically solve the associated non-Hermitian Riemann problem for various initial conditions. Due to the lack of translation symmetry, the resulting long-time dynamics show a strong dependence on the location of the step relative to the gain-loss distribution. This is in sharp contrast to the classical NLS Riemann problem (in the absence of potential), where the dynamics are generally independent of the step location. This fact leads to {a diverse array of} wave pattern dynamics that are otherwise absent. In particular, various novel gain-loss generated near-field features are observed, which in turn drive the optical flows in the far-field. {These far-field non-Hermitian counter-flows could be comprised of various rich nonlinear wave phenomena, including DSW-DSW, DSW-rarefaction, and soliton-DSW interactions. A manuscript containing the results has been submitted to Nonlinearity \\\\cite{chandramouli2023nonHermitian}.} \\\\end{itemize}