ASA 126th Meeting Denver 1993 October 4-8

3aUW10. Description of a noise model for shallow water: RANDI-III.

J. Ernest Breeding, Jr.

Naval Res. Lab., Stennis Space Center, MS 39529-5004

Marshall Bradley Melanie Hebert Walt McBride

Planning Systems, Slidell, LA 70458

Version III of the research ambient noise directionality (RANDI-III) noise model is described and illustrated. The objective of the model is to make predictions of the ambient noise at low to mid frequencies (10 to several hundred Hz) for highly variable environmental conditions typical of shallow water and coastal areas. The receiver can be either a horizontal or vertical line array. Shipping and local wind are assumed to be the dominant sources of noise. Ships are treated as discrete sources of noise. The ship noise is propagated to the elements of the receiver using a wide-angle finite element parabolic equation. The contributions from all ships are added coherently. The environmental and shipping information are automatically extracted from several databases. [Research supported by The Office of Naval Research, Program Element 62435N with technical management provided by the Naval Research Laboratory, Stennis Space Center, MS.]