Propagation Of Sound In Porous Media Modelling Sound Absorbing Materials

Propagation of Sound in Porous Media

"The first edition of this book is considered the bible of this topic... Suffice it to say that there is no other published treatise that approaches the depth of treatment offered by this book. The coverage is the state of the published art, while the added contents cover the new known developments in the field." Haisam Osman; Technology Development Manager, United Launch Alliance This long-awaited second edition of a respected text from world leaders in the field of acoustic materials covers the state of the art with a depth of treatment unrivalled elsewhere. Allard and Atalla employ a logical and progressive approach that leads to a thorough understanding of porous material modelling. The first edition of Propagation of Sound in Porous Media introduced the basic theory of acoustics and the related techniques. Research and development in sound absorption has however progressed significantly since the first edition, and the models and methods described, at the time highly technical and specialized, have since become main stream. In this second edition, several original topics have been revisited and practical prediction methods and industrial applications have been added that increase the breadth of its appeal to both academics and practising engineers. New chapters have also been added on numerical modeling in both low (finite element) and high frequency (Transfer Matrix Method). Collating ‘must-have’ information for engineers working in sound and vibration, Propagation of Sound in Porous Media, 2nd edition offers an indisputable reference to a diverse audience; including graduate students and academics in mechanical & civil engineering, acoustics and noise control, as well as practising mechanical, chemical and materials engineers in the automotive, rail, aerospace, building and civil industries.

Propagation of Sound in Porous Media

This book has grown out of the research activities of the author in the fields of sound propagation in porous media and modelling of acoustic materials. It is assumed that the reader has a background of advanced calculus, including an introduction to differential equations, complex variables and matrix algebra. A prior exposure to theory of elasticity would be advantageous. Chapters 1-3 deal with sound propagation of plane waves in solids and fluids, and the topics of acoustic impedance and reflection coefficient are given a large emphasis. The topic of flow resistivity is presented in Chapter 2. Chapter 4 deals with sound propagation in porous materials having cylindrical pores. The topics of effective density, and of tortuosity, are presented. The thermal exchanges between the frame and the fluid, and the behaviour of the bulk modulus of the fluid, are described in this simple context. Chapter 5 is concerned with sound propagation in other porous materials, and the recent notions of characteristic dimensions, which describe thermal exchanges and the viscous forces at high frequencies, are introduced. In Chapter 6, the case of porous media having an elastic frame is considered in the context of Biot theory, where new topics described in Chapter 5 have been included.

Propagation of Sound in Porous Media