Plenary Lecture

Macrosonics: Sound as a Source of Energy

Professor Juan A. Gallego-Juarez
Institute of Acoustics
CSIC, Madrid
Spain
E-mail: jgallego@ia.cetef.csic.es

Abstract: The field of high-amplitude acoustic waves, regardless of frequency, is known as Macrosonics. As well known, Acoustics may be divided into three main branches according to the frequency spectrum and the hearing characteristics imposed by the frequency. These are: Infrasonics (0-20 Hz), Sonics (20Hz-20kHz) and Ultrasonics (higher than 20 kHz).
Besides frequency other wave parameters, as intensity, may influence broadly the generation, propagation and application of acoustic waves. Therefore another division of the acoustic field could be into two branches such as low and high-amplitude acoustics. Low-amplitude waves are those wherein the primary objective is transmitting information through or about the medium, without modifying it. On the contrary, high-amplitude waves are those which may produce permanent changes in the propagation medium and that, generally, are used to this purpose.
Macrosonics is then the part of Acoustics devoted to high-amplitude waves and their applications. As high-amplitude waves are finite amplitude waves, their behaviour must be described by the equations of the nonlinear acoustics. The applications of macrosonic waves are generally based on the adequate exploitation of the nonlinear phenomena associated to the high amplitudes, such as wave distortion, acoustic saturation, radiation pressure, streaming, cavitation in liquids and the formation and motion of dislocations in solids.
This lecture will review the later advances in the generation and application of macrosounds as well as the basic phenomena there involved.

Brief Biography of the Speaker:
Juan A. Gallego-Juarez, is a Research Professor at the Spanish Council for Scientific Research (CSIC) where he is Former Director of the Institute of Acoustics and of the Center for Physics Technologies and founder of the group of Ultrasonics. His research work has always been related to ultrasonics, particularly high-power ultrasonics, transducers and applications.
He is the author of over 200 publications and 40 patents and holds an honorary doctorate from the University of Santiago de Chile. He was a member of the Board of the International Commission on Acoustics since 1999 until 2007, Chairman of the 19th International Congress on Acoustics 2007 and Organizer of the Ultrasonics International 89. He is a member of the Steering Committee of the International Congress on Ultrasonics and of the Board of the Spanish Acoustical Society. He is a Fellow of the Acoustical Society of America and of the British Institute of Acoustics. He is Associate Editor for Ultrasonics of the European Journal Acta Acustica/Acustica.