Movement of Acoustic Energy in the Ocean

✍ Scribed by Vladimir A. Shchurov

• Publisher: Springer
• Year: 2022
• Tongue: English
• Leaves: 196
• Category: Library

✦ Synopsis

This book highlights the advantages of the vector-phase method in underwater acoustic measurements and presents results of theoretical and experimental studies of the deep open ocean and shallow sea based on vector-phase representations. Based on the physical phenomena discovered and compensation of counter streams of energy and vortices of the acoustic intensity vector, processes of transmitting acoustic energy of a tonal signal in the real ocean are described. The book also discusses the development of advanced detection tools based on vector-phase sonar. This book provides useful content for professionals and researchers working in various fields of applied underwater acoustics.

✦ Table of Contents

Preface by Vladimir A. Shchurov: From Publication in Russian, 2019 (Translated from the Russian)
Acknowledgements
From the Editor of Publication in Russian, 2019 (Translated from the Russian)
Contents
1 Vector Representation of the Acoustic Field
1.1 Introduction
1.2 Scalar and Vector Characteristics of the Acoustic Field
1.3 Differential Phase Relationships in Complex Acoustic Vector Fields
1.4 Instantaneous and Average Acoustic Intensity
1.5 Auto- and Cross-Spectral Energy Densities
1.6 Frequency Coherence Function
1.7 Complex Intensity Vector
1.8 Temporal Coherence Function
1.9 Fourth Statistical Moment of Acoustic Intensity
1.10 Conclusions
References
2 Theory and Technique of Vector-Phase Underwater Acoustic Measurements
2.1 Introduction
2.2 Necessity and Sufficiency of the Vector-Phase Approach in Acoustics
2.3 Principle of Measuring the Sound Particle Velocity in an Acoustic Wave
2.4 Vector Acoustic Receiver
2.4.1 Basic Specifications for a Vector Receiver
2.4.2 Piezoceramic and Electrodynamic Vector Receivers
2.5 Combined Acoustic Receiver
2.6 Combined Underwater Acoustic Receiving Systems
2.6.1 Features of Acoustic Measurements in the Ocean
2.6.2 Bottom-Mounted Combined Receiving Systems
2.6.3 Free-Drifting Combined Telemetry Systems
2.6.4 Features of Vector Receiver Suspension in Free-Drifting Receiving Systems
2.6.5 Vector Receiver Systems on Unmanned Underwater Vehicles (Gliders)
2.7 Counterparts Outside Russia
2.8 Units of Measurement and Relative Levels of Measured Values
2.9 Conclusions
References
3 Phenomenon of Compensation of Intensities of Reciprocal Energy Fluxes
3.1 Introduction
3.2 Experimental Observations of Intensity Compensation
3.2.1 Design of Experiment in the Deep Open Ocean
3.2.2 Example of Vertical Compensation of Tone Signal and Underwater Ambient Noise Along the Z Axis
3.2.3 Example of Horizontal Compensation in the Shallow Water Waveguide
3.3 Compensation of Intensity Over a Broadband of Signal and Dynamic Underwater Acoustic Noise in the Deep Open Ocean
3.3.1 Experimental Setup and Technique
3.3.2 Research Results
3.4 Conclusions
References
4 Vortices of Acoustic Intensity Vector in the Shallow Water Waveguide
4.1 Introduction
4.2 Fundamental Relationships
4.2.1 Acoustic Pressure, Particle Velocity, Intensity Vector
4.2.2 Vector-Phase Characteristics of the Acoustic Field
4.2.3 Energy Streamlines
4.2.4 Vortex Generation Mechanism
4.3 Vortex Structure of the Interference Field in a Shallow Water Waveguide
4.3.1 Mathematical Processing of Vector Acoustic Signal
4.3.2 Modes and Vortices
4.4 Dynamics of Local Vortices
4.4.1 Properties of the Vector Field in the Region of Destructive Interference
4.4.2 Vortex of the Acoustic Intensity Vector as a Real Physical Object
4.5 Conclusions
References
5 Observing Weak Signal in Diffuse, Partially Coherent and Coherent Acoustic Noise
5.1 Introduction
5.2 Noise Immunity of an Individual Combined Receiver in the Case of a Tonal Signal
5.3 Noise Immunity in the Case of a Broadband Signal
5.4 Vector-Phase Passive Acoustic Sonar
5.4.1 Operating Principle of the Passive Sonar
5.4.2 Sonar Data Processing Sequence
5.4.3 Fourier and Hilbert Signal Processing Sequences
5.5 Conclusions
References
6 Vector-Phase Experimental Technique, Expeditions, Conferences
6.1 Field Research
6.1.1 R/V Callisto Cruise. Kuril–Kamchatka Chain. May–June 1979
6.1.2 Northwestern and Central Pacific. R/V Balkhash Cruise. 1983
6.1.3 Northwestern and Central Pacific; Indian Ocean. R/V Akademik Vinogradov. 1990
6.2 Shallow Water Acoustic Research Coastal Expeditions
6.3 International Relations
6.3.1 People’s Republic of China
6.3.2 USA and UK
6.4 Promising Areas
6.4.1 Low-Frequency Acoustic Intensity Interferometer. Investigation of Coherent Properties of Acoustic Intensity in Spatially Distanced Points of Acoustic Field Using the Correlation Theory of Coherence
6.4.2 Vector Geophone. Acoustic Studies at the Water–Bottom Interface of the Shallow Water Waveguide
Appendix A Monochromatic Acoustic Vector Field. Fundamental Relationships
A.1 Introduction
A.1.1 Complex Description of Harmonic Vector Acoustic Fields
A.1.2 Plane and Spherical Waves
A.1.3 Analytic Signal
A.1.4 Spectral Density of the Analytic Signal. Hilbert Transform
A.1.5 Differential Vector Field Relations
Appendix B Fourth Statistical Moment of the Acoustic Vector Field
Appendix C Some International Publications (Patents and Articles) On Vector Acoustics in the Past Two Decades
Bibliography