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Chapter 1 (by T. Kundu) in this book is the same as that in I and it deals with basic equations governing the deformation of a linearly elastic continuum. The treatment of plane har- monic wave propagation in infinite, semi–infinite, and layered media follows that found in standard textbooks. This chapter also contains discussion of sound waves in homogeneous fluids and solids surrounded by fluids. The chapter has several worked out problems as well as exercise problems that should be useful to the graduate students. Researchers and practitio- ners will find this chapter lacking in a comprehensive treat- ment of elastic waves in anisotropic and composite media.
A clear discussion of phase, group, and energy velocities and slowness surfaces is also missing. A very brief (and necessarily incomplete) description of waves in anisotropic media can be found later in Chapter 10.
A numerical technique using distributed point sources (DPSM) to model the acoustic and elastic fields generated by a transducer placed in the fluid in contact with another fluid or an isotropic elastic solid is presented in Chapter 2 (by T. Kundu, D. Placko, S. Das, T. Bore, and E.K. Rahani). The authors have developed this method in recent years to solve several problems of practical interest. The method was pre- sented in I (Chapter 2, by D. Placko and T. Kundu). Chapter 2 in this book is an updated version of the previous review.
Electromagnetic nondestructive evaluation techniques are reviewed in Chapter 3, by P.B. Nagy. A brief introduction to electromagnetic wave propagation is given first. This is fol- lowed by the theory of eddy currents and Dielectric inspec- tion, and thermoelectric inspection. This chapter has many example problems and extensive references that will be very useful to students and practitioners.
The DPSM discussed in Chapter 2 is extended to solve elec- trostatic and electromagnetic problems in Chapter 4. Here Placko, Bore and Kundu review their work on modeling and imaging the effects of cracks or interfaces on the fields gener- ated by probes.
Guided elastic waves in homogeneous and layered plates have been extensively studied in recent years. Two recent mono- graphs, Elastic waves in composite media and structures:
“a valuable addition to the literature on nondestructive evaluation of materials and structures”
with applications to ultrasonic nondestructive evaluation,
by S.K. Datta and A.H. Shah, and Physical ultrasonics of composites, by S.I. Rokhlin, D. E. Chimenti, and P.B. Nagy, contain comprehensive treatments (with extensive references) of guided waves in single and multiple layered composite plates. They also discuss waves in periodic layered composite plates which is important in the context of multiple layered composite plates. T. Kundu presents a somewhat incomplete review in sections 5.1 – 5.7 of Chapter 5 (Guided waves for plate and pipe inspections) with very few references and this is the same review that appeared in I (Chapter 4). Sections 5.8
– 5.9 are devoted to circumferential and axial wave propaga- tion in cylindrical pipes. A more comprehensive treatment of circumferential waves in pipes was presented by J. Qu and L. Jacobs in I (Chapter 5). A comprehensive treatment of axial waves in composite cylinders can be found in the monograph by Datta and Shah.
Nonlinear ultrasonic waves provide an important tool to characterize material defects (dislocation, cracks, and metal fatigue), microstructure, effects of precipitation, etc. Chapter 6 (by J.H. Cantrell) is a good review of fundamental equa- tions and their applications to the measurements of acoustic harmonics generated from the nonlinear interactions of an incident wave with basic lattice configurations of anharmonic materials, microstructures, etc. The review also includes study of acoustoelasticity to measure state of stress in the material. The material covered in this chapter is basically the same as in Chapter 6 of I, with an update of recent works on fatigue damage, precipitate induced harmonic generation, and non- linear dislocation dynamics.
Nonlinear elastic waves in a bounded homogeneous isotropic solid are investigated in Chapter 8 (by J.-Y. Kim, L. J. Jacobs, and J. Qu). Here, the focus is on secondary wave generation from a primary wave due to quadratic nonlinearity. Rayleigh waves in a semi – infinite medium and Lamb waves in a plate are treated as examples. This provides a good review of current work and motivation for further research.
Theory and application of laser generated ultrasonic waves in the thermoelastic regime has been reviewed in Chapter 7 (by S. Krishnaswamy and F. Zhang). This is an updated version
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