舰船尾流声散射和几何特征试验

Sound scattering and geometric characteristics of ship wakes

为了研究舰船声尾流的散射特性和几何特征,采用水平窄波束和垂直多波束同时基测量方法,研制和设计了舰船声尾流的海上测试系统和测试方法,进行了海上测试,获取了舰船声尾流在水平方向和垂直方向的声散射图像,并首次获得了舰船声尾流的截面形状和立体图.研究和分析了不同舰船不同航速下尾流的声散射特性和几何特征,结果表明舰船尾流的体积散射强度小于-10 dB,最大深度为吃水深度的1.5～2倍,最大宽度为舰船宽度的7倍,比国外文献中利用光学测量的声尾流宽度要宽.最后从舰船声尾流声散射特性和几何特征中提取了舰船声尾流的10 min的持续时间.

In order to study the scattering properties and geometric characteristics of the wakes of ships,the authors used a same time based sound measuring technique with a horizontal narrow beam and a vertical multi-beam.On this basis they developed and designed a test system and test method for measuring the wakes of ships using sound.They also derived an acoustic scattering image for ship wakes in both the horizontal and the vertical directions.This work generated a sectional shape and three-dimensional diagram of ship sound wakes.Wake acoustic scattering characteristics and geometric characteristics for different ships at different speeds were studied and analyzed.It was shown that the volume scattering strength of the wake was less than-10 dB,the max depth of the wake was about 1.5 to 2 times the vessel＇s draft and the maximum width of the wake was seven times the width of the ship.This width was more than that shown by optical testing according to published data.Finally,a persistence time of about ten minutes for feature parameters was seen from characteristics of sound wake acoustic scattering as well as geometric characteristics.