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BOOK REVIEWS exposition of the fundamentals of continuum mechanics, much of the book is concerned with classical theories and the mathematical techniques used in those theories. The longer chapters are on viscous flow, incompressible and compressible inviscid flow, and infinitesimal elasticity. In addition there are chapters on viscoelasticity, plasticity, finite elasticity, and Reiner-Rivlin fluids, but there is quite properly less emphasis on these subjects. The text is full of worked examples, which illustrate the use of a wide variety of mathematical techniques. There are many interesting problems at the end of each chapter, and a solution section in which these problems are worked out in detail. Because of this emphasis on problem-solving, the book gives a much more complete picture of the nature of continuum mechanics than those which cover the fundamentals alone. Flow-Induced Vibration.

Measurements are made of vortex-induced vibration of an elastically supported circular cylinder in water with reduced velocity (U/fnD) from 2 to 12, damping factors (ζ) from 0.2% to 40% of critical damping, mass ratios (m/ρD2) from π/2 to π/17, and transverse, inline, and combined inline and transverse motions at Reynolds numbers up to 150,000. Effects of mass, damping, Reynolds number, and strakes on vortex-induced vibration amplitude, frequency, entrainment, and drag are reported.

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The influence of a transverse sound wave on vortex shedding from a rigid circular cylinder in a duct has been explored at Reynolds numbers from 20000 to 40000. In the absence of sound, the vortex shedding is found to consist of strings of coherent cyclic events which have frequencies that wander randomly about the nominal vortex-shedding frequency. Application of sound at the vortex-shedding frequency eliminates this wander and correlates the shedding along the cylinder axis. The frequency of vortex shedding can be shifted by sound applied either above or below the nominal vortex-shedding frequency. This entrainment is produced by the velocity induced by the sound wave rather than by the sound pressure. These phenomena are also observed in tube rows.

A model is presented for the analysis of the response of structural systems excited by vortex shedding. The model is based on the introduction of a hidden variable to describe the fluid dynamic effects. Model parameters may be determined from experimental data for fixed and forced elements and the model used to predict the response of elastically mounted elements. Analytical model predictions are compared with experimental results for a circular cylinder.

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