Accession Number : AD0250306

Title :   NORMAL MODE THEORY OF SOUND PROPAGATION IN LIQUID-LIQUID-SOLID LAYERED MEDIA

Corporate Author : RHODE ISLAND UNIV KINGSTON NARRAGANSETT MARINE LAB

Personal Author(s) : DIESENDRUCK,L.

Report Date : DEC 1960

Pagination or Media Count : 1

Abstract : AN INVESTIGATION WAS MADE TO INTERPRET THE RESULTS OF UNDERWATER EXPLOSION MEASUREMENTS CARRIED OUT IN SHALLOW WATER. THE EXISTING CONDITIONS ARE THAT BOTH SOURCE AND RECEIVER ARE IN A WATER LAYER ABOVE A LAYER OF SEDIMENT WHICH, IN TURN, IS OVER ROCK. THE SITUATION IS THAT OF A LIQUID-LIQUID-SOLID LAYERED MEDIUM AND THE USUAL ASSUMPTIONS FOR UNDERWATER SOUND PROPAGATION SHOULD RESULT IN AN EXPRESSION FOR THE POTENTIAL IN THE WATER LAYER IN THE FORM OF AN INTEGRAL. IN THE DISCUSSION BY C. B. OFFICER(INTRODUCTION TO THE THEORY OF SOUND TRANSMISMISSION WITH APPLICATION TO THE OCEAN, MCGRAW-HILL, 1958) OF THE TWO LAYERED LIQUID-LIQUID CASE, THE RESULTING INTEGRAL OBTAINED BY THE USUAL METHOD OF SIMULTANEOUS SOLUTION OF BOUNDARY CONDITIONS IS SHOWN TO BE EQUIVALENT TO ONE OBTAINED BY USING THE PARTIAL NORMAL AMPLITUDES OF THE WAVES AND BY TAKING INTO ACCOUNT CHANGES IN PHASE DUE TO PATHLENGTHS AND REFLECTIONS. A GENERAL EXPRESSION FOR THE POTENTIAL INTEGRAL IN A LAYER WAS OBTAINED WHERE THE EFFECTS OF ALL OTHER LAYERS ARE REPRESENTED BY REFLECTION COEFFICIENTS AT THE BOUNDARIES. IF THERE ARE MORE THAN 2 LAYERS, THESE HAVE TO BE CONSIDERED AS EFFECTIVE REFLECTION COEFFICIENTS. THE EFFECTIVE REFLECTION COEFFICIENTS FOR 3 (OR MORE) LAYERED CASES IS OBTAINED AND THE POTENTIAL INTEGRAL IS EXPLICITLY OBTAINED FOR THE LIQUIDLIQUID-LIQUID AND THE LIQUID-LIQUID-SOLID CASES

Descriptors :   *SOUND TRANSMISSION, *UNDERWATER EXPLOSIONS, *UNDERWATER SOUND, MATHEMATICAL ANALYSIS

Distribution Statement : APPROVED FOR PUBLIC RELEASE