Acoustical Society of America
R. Bruce Lindsay Award - 1992

Anthony A. Atchley

Anthony Armstrong Atchley was born on 23 June 1957 in Lebanon, Tennessee, the son of Kenneth and Martha Jean Atchley. He attended Castle Heights Military Academy from the fourth grade through high school, graduating in 1975. While at Castle Heights he excelled as a student and demonstrated from an early age the organizational and leadership skills that characterize him today. When his fifth grade class was to make a presentation before their parents one day and the public address system suddenly failed, pandemonium was about to break out. Anthony immediately took charge, settled his classmates and quickly corrected the malfunction—perhaps this was his first introduction to acoustics, and to scientific problem-solving. While growing up in rural Tennessee, he spent most of his summers on his grandparents' farm with his older brother Kenneth, where he learned the value of hard work and nurtured the experimental skills of equipment repair and accommodation to limited resources. As a senior at Castle Heights, he captained the drill team to the highest score ever given at that time in a statewide competition, demonstrating at an early age his impressive leadership skills.

After high school, he attended the University of the South, where he majored in physics but was also taught to appreciate the humanities and to develop broad interests, perhaps one of his strongest characteristics. In 1979, he entered graduate school at the New Mexico Institute of Mining and Technology, where he studied the relationships between lightning and precipitation. At New Mexico, he was greatly influenced by Prof. C. B. Moore, who instilled in him an enthusiasm for physics and, through Prof. Moore's example, to strive for excellence in both research and teaching. His work in lightning research led him to the University of Mississippi, where he worked with Henry Bass and Roy Arnold on the underwater noise produced by lightning strikes.

As a graduate student in the Physics Department at Ole Miss, he was soon recognized as the spokesperson for his fellow students, organizing them to study groups or to provide free tutorial assistance to the undergraduates. He was regarded by the faculty almost as a peer and, when a mid-year retirement of a faculty member occurred, Anthony was asked to teach two undergraduate courses, an unprecedented occurrence for a Department who pride themselves on the quality of their teaching. When the students' evaluations at the end of the semester ranked his near the top of all the courses, few of his "fellow faculty" were surprised.

Anthony chose for his dissertation topic the problem of explaining the nucleation of acoustic cavitation, with Larry Crum as his supervisor. When an acoustic field of sufficient amplitude is applied to liquids, they often fail to survive the negative tensile stresses imposed by the field and a vapor cavity is created. If the conditions are optimized, this cavity can grow rapidly during the negative pressure cycle as it fills with vapor. The subsequent positive pressure can then drive the bubble into a violent collapse, producing violent shock waves, or high-speed liquid jets, or even sonoluminescence. Theoretically, cavitation should be a rare phenomenon, because the intermolecular forces that hold the molecules of liquids together are quite large; it is only when a local inhomogeneity exists in the liquid that liquid rupture can occur. Anthony examined the various models of cavitation nucleation and realized that although the models utilized a variety of nuclei, from particulate matter to stabilized microbubbles, the threshold for cavitation inception in water, for example, was the same all over the world. Working with Andrea Prosperetti at Johns Hopkins, he demonstrated that the actual nucleus was relatively unimportant, that cavitation thresholds depended primarily on liquid characteristics and on bubble dynamics, universal quantities that ensured a similar universal threshold.

After a semester as a "visiting" Assistant Professor of Physics at Ole Miss, Anthony was soon in a real quandry. He had been offered a tenure-track position at the Naval Postgraduate School (NPS) and a Hunt Fellowship to work with Bob Apfel at Yale. Unable to choose between the two, he chose both, by convincing Steve Garrett and his colleagues at the NPS that they should wait a year for him to undertake a research project in cavitation at Yale. There he developed, together with Leon Frizzell and Ron Roy, a sensitive cavitation detection system that led to the examination of cavitation produced by diagnostic ultrasound devices.

In 1986, Anthony joined the faculty of the Naval Postgraduate School where he immediately immersed himself in a variety of research projects and lecture courses. At the NPS, an active research effort was underway on the topic of thermoacoustic heat transport. Anthony was soon an active contributor to that group effort; working with Steve Garrett and Tom Hofler, he performed experiments on the thermoacoustic phenomenon at high acoustic amplitudes and on the onset of thermoacoustic oscillations.

Although very active as a researcher, he did not neglect his many talents and his love for teaching. He soon became a favorite of students and within his first three years had supervised eight Master's theses. Anthony also took on administrative duties and became Chairman of the Engineering Acoustics Academic Committee (EAAC), which administers much of the acoustics efforts at the NPS. He performed so well in these duties that he was "deep-selected" for promotion to Associate Professor and awarded tenure two years in advance of normal, a rare, if not unprecedented, occurrence at NPS. He also wooed Mary Setliff, the Physics Teaching Lab Coordinator; they were soon married, and spent their honeymoon at a meeting of this Society. Anthony and Mary are the parents of twin girls, Amber and Carina.

Anthony's contributions to our Society have similarly been outstanding. Since 1984, he has presented 13 papers at Society meetings, chaired and organized numerous sessions, twice served on the Technical Program Committee, and is a member of the Physical Acoustics Technical Committee, the Committee on Tutorials, and the Committee on Education, which he now chairs.

We have listed his extensive contributions to acoustics, but we wish also to tell you something of the personality of Anthony Atchley. From all those who have known him, we hear reports of a special young man who is always warm and generous, slow to anger, eager to please, willing to help. He has a distinctive character about him that attracts others. By the very force of his personality he can get people around him to volunteer to help, to assist in any way. His mother told us that "he was a perfect child;" we know him as a kind and gentle human being with outstanding gifts. He is given this award for his scientific contributions, but it couldn't happen to a nicer guy!

LAWRENCE CRUM

HENRY BASS

STEVEN GARRETT