摘要
海面源产生的海洋环境噪声场与海洋声学环境参数紧密相关.研究海洋声学环境参数对海面源产生的噪声场互谱密度的影响,有助于深刻理解此类噪声场空间分布的物理内涵,为其服务于海洋环境参数反演和目标检测定位奠定基础.基于简正波模型推导了海面源产生的环境噪声场的互谱密度函数,通过仿真计算讨论了不同声速剖面与不同海底参数情况下,采用积分的方法计算各号简正波对海洋环境噪声强度的贡献,并用平面波模型计算相同海洋环境下的海底损失进行验证.结果表明,各号简正波对总声场的贡献同时受到声速剖面和海底参数的影响.其中声速剖面对各号简正波对海洋环境噪声强度贡献的影响较大,而海底参数对各号简正波对海洋环境噪声强度贡献的影响相对较小.对于海底参数而言,声速是影响各号简正波对总噪声场贡献的最主要因素;海底密度次之;海底声吸收对海底损失和各号简正波对总噪声场贡献的影响较小.对声速剖面而言,在负梯度声速剖面下,高号简正波对海洋环境噪声场的贡献较大;在正梯度声速剖面下,低号简正波对海洋环境噪声场的贡献较大.
The ocean ambient noise field produced by the sea surface is closely related to the ocean environmental parameters.The influence of ocean environmental parameters on the noise density of the noise field generated by the sea surface source is helpful to understand the physical connotation of the spatial distribution of the noise field and to lay the foundation for the inversion of the underwater acoustic parameters and the object detection and location.Based on the normal mode wave model,the cross-spectral density function of the environmental noise field generated by the sea surface source is deduced.The contribution of the normal mode wave to the ocean noise intensity is calculated by the integral method under different sound velocity profiles and different ocean parameters.We also use the model of plane wave to calculate the seabed loss under the same ocean environment and validate our results.The results show that the contribution of the normal wave to the total sound field is affected by the velocity profile and the ocean envi-ronmental parameters.The influence of the acoustic velocity profile on the contribution of the normal wave to the noise intensity of the ocean environment is relatively large,and the influence of the ocean parameters on the contribution of the normal wave to the marine environment noise intensity is relatively small.For the ocean environmental parameters,the velocity of sound is the most important factor affecting the contribution of the normal waves to the total noise field and the ocean density is the second.By contrast,the bottom sound absorption has little effect on the contribution of the bottom loss and the normal wave to the total noise field.In the case of the velocity gradient,the contribution of the high-order normal wave to the ocean environmental noise field is larger in the low-velocity acoustic velocity profile while the low-order normal wave contributes greatly to the marine environment noise field under the normal gradient velocity profile.
出处
《南京大学学报（自然科学版）》
CAS
CSCD
北大核心
2017年第4期638-645,共8页
Journal of Nanjing University（Natural Science）
基金
国防科学技术大学光电科学与工程学院科研基金(GDJC13-027)
国防科学技术大学科研计划(ZK16-03-31)
关键词
海洋环境噪声
声速剖面
海底参数
简正波
本征函数
ocean ambient noise
sound speed profile
seabed parameters
normal modes
eigenfunction
