Constitutive Equations of Nonlinear Electromagnetic-Elastic Crystals


Book Description

Continuum physics is concemed with the predictions of deformations, stress, temperature, and electromagnetic fields in deformable and fluent bodies. To that extent, mathematical formulation requires the establishment of basic balance laws and constitutive equations. Balance laws are the union of those of continuum thermomechanics and MaxweIl's equations, as coIlected in Chapter 1. To dose the theory it is necessary to formulate equations for the material response to extemal stimuli. These equations bring into play the material properties of the media under consideration. In their simplest forms these are the constitutive laws, such as Hooke's law of dassical elasticity, Stokes' law of viscosity of viscous fluids, Fourier's law of heat conduction, Ohm's law of electric conduction, etc. For large deformations and fields in material media, the constitutive laws become very complicated, in vol ving all physical effects and material symmetry. The present work is concemed with the material symmetry regulations arising from the crystaIlographic symmetry of magnetic crystals. While there exist some works on the thirty-two conventional crystal dasses, exduding the linear case, there exists no study on the nonlinear constitutive equations for the ninty magnetic crystal dasses. Yet the interaction of strong electromagnetic fields with deformable solids cannot be explained without the material sym metry regulations relevant to magnetic crystals. In this monograph, we present a thorough discussion of magnetic symmetry by means of group theory. We consider onlyone scalar function which depends on one symmetric second-order tensor (e. g."







Ferroic Functional Materials


Book Description

The book covers experiments and theory in the fields of ferroelectrics, ferromagnets, ferroelastics, and multiferroics. Topics include experimental preparation and characterization of magnetoelectric multiferroics, the modeling of ferroelectric and ferromagnetic materials, the formation of ferroic microstructures and their continuum-mechanical modeling, computational homogenization, and the algorithmic treatment in the framework of numerical solution strategies.




Giants of Engineering Science


Book Description

Giants of Engineering Science is a biographical monograph examining the life and works of ten of the world’s leading engineering scientists.




Nonlinear Waves in Elastic Crystals


Book Description

The mathematical modelling of changing structures in materials is of increasing importance to industry where applications of the theory are found in subjects as diverse as aerospace and medicine. This book deals with aspects of the nonlinear dynamics of deformable ordered solids (known as elastic crystals) where the nonlinear effects combine or compete with each other. Physical and mathematical models are discused and computational aspects are also included. Different models are considered - on discrete as well as continuum scales - applying heat, electricity, or magnetism to the crystal structure and these are analysed using the equations of rational mechanics. Students are introduced to the important equations of nonlinear science that describe shock waves, solitons and chaos and also the non-exactly integrable systems or partial differential equations. A large number of problems and examples are included, many taken from recent research and involving both one-dimensional and two-dimensional problems as well as some coupled degress of freedom.




Microcontinuum Field Theories


Book Description

Microcontinuum field theories extend classical field theories to microscopic spaces and short time scales. This volume is concerned with the kinematics of microcontinua. It begins with a discussion of strain, stress tensors, balance laws, and constitutive equations, and then discusses applications of the fundamental ideas to the theory of elasticity. The ideas developed here are important in modeling the fluid or elastic properties of porous media, polymers, liquid crystals, slurries, and composite materials.




Fluid and Thermodynamics


Book Description

This third volume describes continuous bodies treated as classical (Boltzmann) and spin (Cosserat) continua or fluid mixtures of such bodies. It discusses systems such as Boltzmann continua (with trivial angular momentum) and Cosserat continua (with nontrivial spin balance) and formulates the balance law and deformation measures for these including multiphase complexities. Thermodynamics is treated in the spirit of Müller–Liu: it is applied to Boltzmann-type fluids in three dimensions that interact with neighboring fluids on two-dimensional contact surfaces and/or one-dimensional contact lines. For all these situations it formulates the balance laws for mass, momenta, energy, and entropy. Further, it introduces constitutive modeling for 3-, 2-, 3-d body parts for general processes and materially objective variable sets and their reduction to equilibrium and non-equilibrium forms. Typical (reduced) fluid spin continua are liquid crystals. Prominent nematic examples of these include the Ericksen–Leslie–Parodi (ELP) formulation, in which material particles are equipped with material unit vectors (directors). Nematic liquid crystals with tensorial order parameters of rank 1 to n model substructure behavior better, and for both classes of these, the book analyzes the thermodynamic conditions of consistency. Granular solid–fluid mixtures are generally modeled by complementing the Boltzmann laws with a balance of fluctuation (kinetic) energy of the particles. The book closes by presenting a full Reynolds averaging procedure that accounts for higher correlation terms e.g. a k-epsilon formulation in classical turbulence. However, because the volume fraction is an additional variable, the theory also incorporates ‘k-epsilon equations’ for the volume fraction.




Continuum Mechanics of Electromagnetic Solids


Book Description

This volume is a rigorous cross-disciplinary theoretical treatment of electromechanical and magnetomechanical interactions in elastic solids. Using the modern style of continuum thermomechanics (but without excessive formalism) it starts from basic principles of mechanics and electromagnetism, and goes on to unify these two fields in a common framework. It treats linear and nonlinear static and dynamic problems in a variety of elastic solids such as piezoelectrics, electricity conductors, ferromagnets, ferroelectrics, ionic crystals and ceramics. Chapters 1-3 are introductory, describing the essential properties of electromagnetic solids, the essentials of the thermomechanics of continua, and the general equations that govern the electrodynamics of nonlinear continua in the nonrelativistic framework (e.g. Maxwell's equations, the fundamental balance laws of continuum mechanics, basic thermodynamical inequalities for electromagnetic continua, jump relations for studying the propagation of shock waves, nonlinear constitutive equations for large classes of materials).The remainder of the text presents in detail special cases, applications, solved problems, and more complex schemes of electromagnetic matter. Chapters 4 and 5 examine material schemes whose description relies on the above-mentioned equations. Chapters 6 and 7 are more advanced, reporting on recent progress in the field.Suitable for graduate teaching, the volume will also be useful to research workers and engineers in the field of electromagnetomechanical interactions, and to those interested in the basic principles, mathematical developments and applications of electroelasticity and magnetoelasticity in a variety of solid materials, such as crystals, polycrystals, compounds and alloys.




Electrodynamics of Continua II


Book Description

This is the second volume of a two-volume set presenting a unified approach to the electrodynamics of continua, based on the principles of contemporary continuum of physics. The first volume was devoted mainly to the development of the theory and applications to deformable solid media. This volume extends the developments of the first volume to richer and newer grounds. It contains discussions on fluid media, magnetohydrodynamics, eletrohydrodynamics and media with more complicated structures. With the discussion, in the last two chapters, of memory-dependent materials and non-local E-M theory, the authors account for the nonlocal effects arising from motions and fields of material points at past times and at spatially distant points. This discussion is included here to stimulate further research in these important fields, which are presently in development stages. The second volume is self-contained and can be studied without the help of volume I. A section summarizing the constitutive equations and the underlying physical ideas, which were presented in more detail in the first volume, is included. This volume may be used as a basis for several graduate courses in engineering schools, applied mathematics and physics departments. It also contains fresh ideas and will stimulate further research in the directions the authors outline.