CONTENTS 



LIST OF SYMBOLS USED IN TEXT. . .page iv 



I. INTRODUCTION. . . 1 



II. METHODS OF MEASUREMENT. . . 3 

 Field Methods. . . 3 



Laboratory Methods: Plane Wave Propagation. . . 4 

 Laboratory Methods: Three-Dimensional Wave 



Propagation. . . 6 

 Soft Wall Cavity Resonators. . . 8 

 Influence of Air Bubbles. . . 9 



III. DESIGN CONSIDERATIONS. ..11 

 Cylindrical and Spherical Cavities. . . 11 

 Box-Shape Cavities. . .13 



IV. THEORETICAL DISCUSSION. . .25 



Acoustical Wave Equation for Viscous Fluids. . . 26 

 Some Special Solutions of the Wave Equation. . .41 



V. EXPERIMENTAL PROGRAM. ..60 

 Observational Platform. . . 60 

 Experimental Procedure. . . 62 

 Discussion of Results. . . 73 



VI. SUMMARY AND CONCLUSIONS. ..97 

 Primary Results. . .97 

 Suggestions for Future Studies. . . 98 



REFERENCES. . . 101 



ILLUSTRATIONS 



1-2 Schematics of preliminary and final cavity designs. . .page 15 



3 Sound transducers (preliminary and final models). . . 17 



4 Diagrams of measuring systems. . . 19 



5-7 Reverberation curves obtained with Briiel and Kjaer recorder. . . 21-23 

 8 Photograph of data -collecting equipment. . . 24 

 9-14 Calibration data recorded under various conditions. . . 6 7-69 

 15 Reverberation curves using data of figures 5, 6, and 7. . . 71 

 16-32 Attenuation values as determined from measurements on 

 sea water samples under various conditions. . . 77-86 



