潜艇结构水下低频声辐射特性分析

Analysis of Low Frequency Acoustic Radiation Characteristics of Underwater Submarine Structure

对某型全尺寸单层潜艇简化模型,基于流固耦合声学有限元与自动匹配层(FEM-AML)方法,考虑自由海面环境,通过双向流固耦合原理,分析在典型机械设备激励载荷作用下,潜艇结构位于不同潜深时,其在海底水平方向1500 m范围的低频声场辐射特性,结果表明,1~150 Hz频段内,低频率点对潜艇声隐身性影响较大,在潜艇艏艉方向有明确的指向性,容易被声呐探测到;随着潜深增加,潜艇结构辐射声压幅值变大,指向性尖角更细,方向更明确,对潜艇隐身性威胁更大。此外,潜艇结构受自身形状和尺寸的影响,研究潜艇结构声辐射特性时,1500 m范围内辐射的声场不能直接采用点源辐射声场近似。

Taking a simplified model of a full-size single-layer submarine as research object,based on the fluid-structure coupling acoustic finite element method and the automatic matching layer(FEM-AML)method,considering the free sea surface,and through the bidirectional fluid-solid coupling principle,the low-frequency sound field radiation characteristics of the submarine structure in the horizontal direction of the seabed in the range of 1500 m were analyzed when the submarine structure is located at different depths under the excitation load of typical mechanical equipment.The results showed that in the frequency range of 1~150 Hz,the low frequency point has a great influence on the acoustic stealth of submarine,and has a clear directivity in the bow and stern direction of submarine,which is easy to be detected by enemy sonar.With the increase of submarine depth,the amplitude of radiated sound pressure of submarine structure becomes larger,the directivity angle of sound pressure is thinner,the direction is clearer,and the threat to submarine stealth is greater.In addition,due to the shape and size of the submarine structure,when studying the acoustic radiation characteristics of the submarine structure,the radiated sound field within 1500 m cannot be directly approximated by the point source radiated sound field.