Acoustics Fundamentals, Measurements with Underwater Applications

This four day course is intended for engineers and other technical personnel and managers who have a work-related need to understand basic acoustics concepts and how to measure and analyze sound. This is an introductory course and participants need not have any prior knowledge of sound or vibration. Each topic is illustrated by relevant applications, in-class demonstrations, and worked-out numerical examples. Since the practical uses of acoustics principles are vast and diverse, participants are encouraged to confer with the instructor (before, during, and after the course) regarding any work-related concerns. On-site courses are fully customized to the customer’s applications.

• How underwater sensors work.
• How underwater sensors work.
• How to make proper sound level measurements.
• How to analyze and report acoustic data.
• The basis of decibel (dB) scale used in underwater acoustics.
• How to use third-octave band analyzers and narrow-band spectrum analyzers.
• How acoustic arrays are used to improve target detection.
• How to measure sound propagation loss including surface scatter and bottom penetration.
• How to detect a passive target in a background of ambient and self-noise.
• How to detect an active sonar ping in a background of reverberation noise.

1. Introductory Concepts. Sound in fluids and solids. Sound as particle vibrations. Waveforms and frequency. Sound energy and power consideration
2. Acoustic Waves in Water. Plane and spherical acoustic waves. Spreading loss and plane wave equivalent. Sound pressure, intensity, and power. Decibel (dB) scales used in underwater acoustics. Sound reflection, transmission, and refraction (Snell’s law). Mechanisms of underwater sound absorption.
3. Underwater Acoustic Transducers. Hydrophone and active transducer element designs and response characteristics. Underwater intensity and vector probe designs and operational limitations. Accelerometer designs and frequency response.
4. Sound Measurements. Underwater sound level scales. Octave band analyzers. Narrow band and FFT spectrum analyzers. Detecting tones in noise. Hydrophone calibration techniques.
5. Sound Sources and Arrays. Active sonar design and response characteristics. Directivity patterns of simple and multi-pole sources: monopole, dipole and quadri-pole sources. Acoustic arrays and beamforming. Sound radiation from vibrating machines and structures. Radiation efficiency.
6. Underwater Acoustics. Sound refraction due to temperature, depth, and salinity. Ambient and self-noise consideration. Passive and active sonar equation. Passive and active target detection, tracking, and localization. Reverberation noise: volume, surface, and bottom. Topics of interest to the course participants.

• “Great instructor made the course interesting and informative. Helped clear-up many misconceptions I had about sound and its measurement.”

   

• “Enjoyed the in-class demonstrations; they help explain the concepts. Instructor helped me with a problem I was having at work, worth the price of the course!”

Dr. Alan D. Stuart, Associate Professor Emeritus of Acoustics, Penn State, has over forty years experience in the field of sound and vibration. He has degrees in mechanical engineering, electrical engineering, and engineering acoustics. For over thirty years he has taught courses on the Fundamentals of Acoustics, Structural Acoustics, Applied Acoustics, Noise Control Engineering, and Sonar Engineering on both the graduate and undergraduate levels as well as at government and industrial organizations throughout the country.

Contact this instructor (please mention course name in the subject line)