The Test And Research Of Ocean Ambient Physical Field Characteristic

This subject is from environment noise field test and observation, a part of the tenth five-year plan project "The test and research of Ocean ambient physical field characteristic" charged by Dalian Test&Control Institute .Ocean ambient physic field mainly includes environment noise field , circumstance magentic field, hydraulic pressure field, electric field and so on. Thereinto ambient noise field and environment magnetic field have directly influence to underwater target characteristic research and torpedo fusee design.With the reducing of submarine radiated noise, the understand of improving upon test and evaluate measure is expected at present, we must comprehend the ocean ambient noise of the sea area used to measure radiated noise of low noise submarine, therefore the studies of ambient noise have become many country's research focuses. In this paper, the characteristic of ambient noise is mainly discussed, it can be separated as two part, one is the test of ocean ambient noise, and the other is analysis of ocean ambient noise.At the first part of this paper, we maily introduced the basic idea, the formulae for calculating and the characteristic about the sea area ambient noise,the common knowledge for measuring ambient noise, such as measuring equation, basic measuring system.More over some ways and means of measure ambient noise, including single hydrophone,line array and sound press-vibration speed combination transducer are introduced as well. At the second part of this paper, many characteristics of the ocean ambien noise were researched from different point of view. First of all based on data test from single hydrophone created the ambient noise mathematics model of Dalian sea area,and then the validity of this model is proved by analysing data from line array.In the final,the ambient noise of examination sea area has been tested with combined receiver of the acoustic pressure and three orthogonal components of particle velocity. The composing anddistributing of ambient noise is explored using various analysis method. A total ambient noise field is separated into anisotropy (coherent) and isotropic (diffusive) parts. And the combined receiver gain in the noise field is discussed.