Accession Number : AD0011374


Title :   30 CPS SOUND PROPAGATION IN SHALLOW WATER


Descriptive Note : Technical rept. no. 9


Corporate Author : COLUMBIA UNIV DOBBS FERRY NY HUDSON LABS


Personal Author(s) : Becker, G E ; Carlson, R O ; Frosch, R A ; Poss, H L


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/011374.pdf


Report Date : 15 Apr 1953


Pagination or Media Count : 71


Abstract : The sound field in the neighborhood of a 30-c frequency-stabilized source, operated at a 40-ft depth (AD-4926, Secret), was investigated at 2 locations in Long Island Sound. At the first station the water depth was 120 ft, over a layer of clay and mud about 430 ft deep. The water depth at the second station was about 50 to 60 ft, over a layer of sediment about 100 ft thick. Curves of pressure vs range out to several thousand years showed irregular patterns of maxima and minima with an over-all dependence on range which varies from r to the minus power of 1/2 to greater than r to the minus power of 1. According to normal mode theory, 6 propagating modes were predicted for the station with deeper water and basement depths. A choice of parameters for a three layer model yielded curves which were similar to the experimental curves. At the shallower station on 2 propagated modes were predicted. A pattern similar to the regular pattern expected from the interference of these 2 modes appeared on only one experimental curve.


Descriptors :   *UNDERWATER SOUND , STATIONS , LAYERS , PARAMETERS , WATER , ACOUSTIC FIELDS , BASEMENTS , LONG ISLAND SOUND , MUD , THEORY , DEPTH , CLAY , SEDIMENTS


Subject Categories : Acoustics


Distribution Statement : APPROVED FOR PUBLIC RELEASE