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Pekeris波导环境中的水下运动声场仿真研究 被引量:1
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作者 姚舟磊 于晓林 许伟杰 《声学技术》 CSCD 北大核心 2023年第6期718-725,共8页
对Pekeris波导环境中水下运动声源的声场进行了研究。将Pekeris波导中数值稳定的波数积分解和一维近似的波数积分方法运用于求解运动声源的声场。推导了运动声源声场的二维波数积分表达式,给出一维近似解,并在计算深度格林函数时引入数... 对Pekeris波导环境中水下运动声源的声场进行了研究。将Pekeris波导中数值稳定的波数积分解和一维近似的波数积分方法运用于求解运动声源的声场。推导了运动声源声场的二维波数积分表达式,给出一维近似解,并在计算深度格林函数时引入数值稳定的计算方法。在仿真实验中,首先在自由空间条件下验证了一维近似的波数积分方法的准确性;再结合Pekeris波导中数值稳定的波数积分方法来分析运动声源的声场特性。通过改变波导和声源、接收器条件仿真研究Pekeris波导中运动声源声场的频率展宽和频移特性。 展开更多
关键词 波数积分 运动声源 pekeris波导 数值稳定解法
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一种可稳定计算Pekeris波导中声场的波数积分方法 被引量:7
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作者 骆文于 于晓林 张仁和 《声学学报》 EI CSCD 北大核心 2016年第3期321-329,共9页
提出一种可稳定计算Pekeris波导中声场的波数积分方法,并在此基础上开发出一个数值模型,可用于提供Pekeris波导中声场的精确、稳定的数值解。在这个方法中,由于与深度有关的波动方程齐次解中所有的上行波与下行波均采用了合理的归一化表... 提出一种可稳定计算Pekeris波导中声场的波数积分方法,并在此基础上开发出一个数值模型,可用于提供Pekeris波导中声场的精确、稳定的数值解。在这个方法中,由于与深度有关的波动方程齐次解中所有的上行波与下行波均采用了合理的归一化表示,从而得到的系统方程是无条件稳定的。在简正波方法中,割线积分一般只对近场有显著影响。因此,传统的简正波模型一般都忽略割线积分对声场的贡献。但是,如果某号简正波离割线非常近,则割线积分对非常远距离的声场仍可能有显著影响。在这种情况下,传统的简正波模型由于忽略割线积分的贡献,从而得到的声场结果是不准确的。本文通过数值算例比较本文提出的波数积分模型与传统的简正波模型。数值结果表明,本文提出的模型可以提供精确、稳定的Pekeris波导中声场的数值解,而在某些情况下传统的简正波模型得到的声场结果是不准确的。因此,本文提出的模型可以作为Pekeris波导中声传播问题的标准模型使用。 展开更多
关键词 pekeris 简正波 积分方法 线积分 上行波 数值解 归一化方法 波动方程 声传播 传播损失
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Pekeris水声波导环境中水面和水下状态船体辐射噪声的差异分析 被引量:2
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作者 邹明松 刘树晓 《振动与冲击》 EI CSCD 北大核心 2019年第22期204-209,250,共7页
基于一个实尺度的单层壳水下船舶结构声辐射计算模型,加载典型的船舶机械激励力。采用Pekeris水声波导环境中的船舶三维声弹性分析方法,计算该模型在极浅水环境水面状态下以及浅海环境水下状态下的辐射噪声。通过数值结果的定量分析,揭... 基于一个实尺度的单层壳水下船舶结构声辐射计算模型,加载典型的船舶机械激励力。采用Pekeris水声波导环境中的船舶三维声弹性分析方法,计算该模型在极浅水环境水面状态下以及浅海环境水下状态下的辐射噪声。通过数值结果的定量分析,揭示了极浅水环境水面状态下船体水下辐射噪声存在的一些特点,同时,说明了极浅水环境水面状态与浅海环境水下状态下船体辐射噪声的差异。 展开更多
关键词 船舶 声弹性理论 pekeris水声波导 声辐射
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Pekeris水声波导环境中声压信号采样时段对船舶声源级评定的影响研究 被引量:1
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作者 邹明松 刘树晓 《振动与冲击》 EI CSCD 北大核心 2018年第6期207-211,224,共6页
建立了一个实尺度的单层壳水下船舶结构声辐射计算模型,加载典型的船舶机械激励力。采用Pekeris水声波导环境中的船舶三维声弹性分析方法,模拟有限水深环境中航行船舶的辐射噪声测试状态,开展计算仿真。针对通过舷侧方向的观察点获取内... 建立了一个实尺度的单层壳水下船舶结构声辐射计算模型,加载典型的船舶机械激励力。采用Pekeris水声波导环境中的船舶三维声弹性分析方法,模拟有限水深环境中航行船舶的辐射噪声测试状态,开展计算仿真。针对通过舷侧方向的观察点获取内部激励源作用下的船舶辐射噪声量值问题,探讨了观察点声压信号不同采样时段对船舶声源级评定的影响。在此基础上,给出了有助于更全面地获取船舶辐射噪声频谱特征及使得观察结果更加稳定的声压信号采样时段选取的建议。 展开更多
关键词 船舶 声弹性理论 pekeris水声波导 声压信号 采样时段
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Pekeris波导中垂直发射阵的阵增益快速估计
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作者 衣晓锋 彭大勇 +1 位作者 曾娟 马力 《声学学报》 EI CSCD 北大核心 2020年第3期341-349,共9页
为了利用单换能器的声强级估计垂直发射阵的声强级,研究了Pekeris波导中快速估计发射阵增益的方法。首先,基于等效深度简正波理论,计算了Pekeris波导中垂直发射阵的平均声强,进而得到用模态阶数求和表示的发射阵增益的表达式。然后对模... 为了利用单换能器的声强级估计垂直发射阵的声强级,研究了Pekeris波导中快速估计发射阵增益的方法。首先,基于等效深度简正波理论,计算了Pekeris波导中垂直发射阵的平均声强,进而得到用模态阶数求和表示的发射阵增益的表达式。然后对模态阶数用积分代替求和,并对引入的误差进行修,得到3/2次方衰减场区发射阵增益的快速估计表达式;有效声影区声场由于只剩1阶简正模态,可直接简化得到发射阵增益的快速估计表达式,在海底参数未知时可用海深近似代替等效深度来估计有效声影区的发射阵增益。计算机仿真和海上实验得到的阵增益快速估计误差均小于1 dB,验证了快速估计方法的有效性,这一发射阵增益快速估计方法可以为工程应用提供参考。 展开更多
关键词 发射阵 pekeris 阵增益 快速估计
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Analytical solution based on the wavenumber integration method for the acoustic field in a Pekeris waveguide 被引量:2
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作者 骆文于 于晓林 +1 位作者 杨雪峰 张仁和 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第4期194-205,共12页
An exact solution based on the wavenumber integration method is proposed and implemented in a numerical model for the acoustic field in a Pekeris waveguide excited by either a point source in cylindrical geometry or a... An exact solution based on the wavenumber integration method is proposed and implemented in a numerical model for the acoustic field in a Pekeris waveguide excited by either a point source in cylindrical geometry or a line source in plane geometry. Besides, an unconditionally stable numerical solution is also presented, which entirely resolves the stability problem in previous methods. Generally the branch line integral contributes to the total field only at short ranges, and hence is usually ignored in traditional normal mode models. However, for the special case where a mode lies near the branch cut, the branch line integral can contribute to the total field significantly at all ranges. The wavenumber integration method is well-suited for such problems. Numerical results are also provided, which show that the present model can serve as a benchmark for sound propagation in a Pekeris waveguide. 展开更多
关键词 wavenumber integration technique pekeris waveguide analytical solution branch line integral
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Efficient Computational Approach for Predicting the 3D Acoustic Radiation of the Elastic Structure in Pekeris Waveguides
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作者 QIAN Zhiwen HE Yuanan +2 位作者 SHANG Dejiang ZHAO Haihan ZHAI Jingsheng 《Journal of Ocean University of China》 SCIE CAS CSCD 2022年第4期903-916,共14页
Ocean boundaries present a significant effect on the vibroacoustic characteristics and sound propagation of an elastic structure in practice.In this study,an efficient finite element/wave superposition method(FE/WSM)f... Ocean boundaries present a significant effect on the vibroacoustic characteristics and sound propagation of an elastic structure in practice.In this study,an efficient finite element/wave superposition method(FE/WSM)for predicting the three-dimen-sional acoustic radiation from an arbitrary-shaped radiator in Pekeris waveguides with a lossy seabed is proposed.The method is based on the FE method(FEM),WSM,and sound propagation models.First,a near-field vibroacoustic model is established by the FEM to obtain vibration information on a radiator surface.Then,the WSM based on the Helmholtz boundary integral is used to pre-dict the far-field acoustic radiation and propagation.Furthermore,the rigorous image source method and complex normal mode are employed to obtain the near-and far-field Green’s function(GF),respectively.The former,which is based on the spherical wave decomposition,is adopted to accurately solve the near-field source strength,and the far-field acoustic radiation is calculated by the latter and perturbation theory.The simulations of both models are compared to theoretical wavenumber integration solutions.Finally,numerical experiments on elastic spherical and cylindrical shells in Pekeris waveguides are presented to validate the accuracy and efficiency of the proposed method.The results show that the FE/WSM is adaptable to complex radiators and ocean-acoustic envi-ronments,and are easy to implement and computationally efficient in calculating the structural vibration,acoustic radiation,and sound propagation of arbitrarily shaped radiators in practical ocean environments. 展开更多
关键词 elastic structure acoustic radiation pekeris waveguide wave superposition method Green’s function image source method spherical wave decomposition
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An Efficient Method for Local Base Transform in Pekeris Waveguide with Radiation Condition
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作者 Jianxin Zhu Haibo Chen 《Journal of Applied Mathematics and Physics》 2020年第5期780-792,共13页
In this paper, for the fast computation of the coordinates under the basis of the eigenfunctions of Helmholtz operator, we derive the conjugate operator with the radiation boundary condition. Further, we prove the cro... In this paper, for the fast computation of the coordinates under the basis of the eigenfunctions of Helmholtz operator, we derive the conjugate operator with the radiation boundary condition. Further, we prove the cross orthogonality between the linearly-independent eigenfunctions of the Helmholtz operator and the linearly-independent eigenfunctions of the conjugate operator. The numerical simulations demonstrate the effectiveness of our treatment. 展开更多
关键词 HELMHOLTZ OPERATOR Radiation Boundary Condition CONJUGATE OPERATOR EIGENFUNCTION Expansion ORTHOGONALITY pekeris Waveguide
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Pekeris波导中简正波的复声强及其应用 被引量:19
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作者 余赟 惠俊英 +2 位作者 赵安邦 孙国仓 滕超 《物理学报》 SCIE EI CAS CSCD 北大核心 2008年第9期5742-5748,共7页
在Pekeris波导模型下,关注了简正波的矢量场,讨论了简正波水平复声强和垂直复声强的表述,并分析了其特征.单阶简正波在水平方向是行波,相应的水平复声强仅为有功的;在垂直方向为驻波,相应的垂直复声强仅为无功的.而多阶简正波相互干涉,... 在Pekeris波导模型下,关注了简正波的矢量场,讨论了简正波水平复声强和垂直复声强的表述,并分析了其特征.单阶简正波在水平方向是行波,相应的水平复声强仅为有功的;在垂直方向为驻波,相应的垂直复声强仅为无功的.而多阶简正波相互干涉,因此总声场的复声强既有有功分量,也有无功分量,其中只有有功分量参与声能的输运,但无功分量是反映声场信息的重要组成部分.通过对垂直(交互)复声强无功分量和水平交互复声强有功分量的数值分析,对于甚低频率的点源声场,发现当声源深度变化时,上述声场分量的正负号呈有规变化,当接收传感器置于适当的位置时,通过与一临界深度比较,可以对目标的深度分类,尤其对于水平交互复声强有功分量,可以用来判断声源是在近水面处,还是在水下.最后探讨了复声强和交互复声强的相角,分析了其空间分布规律. 展开更多
关键词 目标深度分类 复声强 矢量场 pekeris波导
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Waveguide invariant estimation in elastic Pekeris waveguide 被引量:3
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作者 ZHU Hanhao PIAO Shengchun +1 位作者 ZHANG Haigang LIU Wei 《Chinese Journal of Acoustics》 CSCD 2017年第1期113-129,共17页
Focus on sound intensity, particle velocity, complex sound intensity and waveguide impedance, the formation mechanism of interference structures in range-frequency domain for the above four kinds of physical quantitie... Focus on sound intensity, particle velocity, complex sound intensity and waveguide impedance, the formation mechanism of interference structures in range-frequency domain for the above four kinds of physical quantities in Pekeris waveguides is analyzed based on Nor- mal Mode Theory. Also, a sea-trial with broadband radiated source is conducted to verify the analysis results. Both the simulation results and the analysis of sea-trial data indicate that, in range-frequency domain, the four kinds of physical quantities will exhibit a stable interfer- ence structure which can be expressed with waveguide invariant /3. Among these quantities, the coherent components of complex sound intensity can better reflect the interference char- acteristics of the waveguide. Finally, a multi-scale linear filter is introduced to deal with the sea-trial LOFAR (Low Frequency Analysis Recording) spectrum, the processing results show that the proposed filter can effectively enhance the interference characteristics in images, and conductively detect and extract striations' information from interference structures in LOFAR spectrum. 展开更多
关键词 Waveguide invariant estimation in elastic pekeris waveguide
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Models for amplitude fluctuation of underwater acoustic narrow band signal based on modified modal scintillation index 被引量:2
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作者 安良 方世良 陈励军 《Journal of Southeast University(English Edition)》 EI CAS 2013年第3期235-241,共7页
A self-normalized statistic the modified modal scintillation index MMSI is proposed and defined as the variance of the modulus of modal excitation normalized by the square of its expected value over some observation i... A self-normalized statistic the modified modal scintillation index MMSI is proposed and defined as the variance of the modulus of modal excitation normalized by the square of its expected value over some observation intervals.It is proved in an analytical form that the MMSI is a depth dependent signature and independent of the source level and the source range under the condition of the ideal waveguide while the classical modal scintillation index MSI depends on both the source level and the source range.The MSI and the MMSI in the Pekeris waveguide at 70 Hz are simulated with different source levels and source ranges by the Kraken normal mode model.The simulation results are consistent with the theoretical deduction.The MMSI probability density functions PDFs of different normal modes for surface and submerged sources are calculated using the mode filtering methods with the same variations of vertical motions.It is indicated that the PDFs can be used to separate the submerged and the surface sources except for the fourth mode. 展开更多
关键词 modified modal scintillation index amplitudefluctuation mode filtering pekeris waveguide
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浅海环境下低频声信号传播特性研究 被引量:9
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作者 祝捍皓 郑广学 +3 位作者 张海刚 郑红 林建民 汤云峰 《上海交通大学学报》 EI CAS CSCD 北大核心 2017年第12期1464-1472,共9页
针对典型浅海海洋环境下的低频声传播问题,以快速场方法为建模手段,以声能流为研究对象,结合具体算例模拟研究了不同浅海环境参数对低频声信号传播特性的影响规律.研究结果表明:矢量场中质点垂直振速传播衰减远大于同点声压与水平振速... 针对典型浅海海洋环境下的低频声传播问题,以快速场方法为建模手段,以声能流为研究对象,结合具体算例模拟研究了不同浅海环境参数对低频声信号传播特性的影响规律.研究结果表明:矢量场中质点垂直振速传播衰减远大于同点声压与水平振速传播损失;海洋环境参数、声源参数、海底声学参数均对低频声信号传播具有重要影响,其中又以海底声速对声能量传播特性的影响最为显著. 展开更多
关键词 浅海pekeris波导 低频声信号 快速场方法 声传播 声能流
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基于双水听器的目标深度辨识
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作者 吴晓潭 黄勇 +1 位作者 高善国 张春华 《应用声学》 CSCD 北大核心 2016年第2期179-188,共10页
随着水下目标越来越安静,探测并区分水下目标变得越来越困难。现在对目标的深度辨识多采用匹配场的方法,但其需要大量的先验知识,由于海洋情况多变复杂,这种方法并不适合进行工程实践。本文旨在探索出一种适用于浅海波导的目标深度辨识... 随着水下目标越来越安静,探测并区分水下目标变得越来越困难。现在对目标的深度辨识多采用匹配场的方法,但其需要大量的先验知识,由于海洋情况多变复杂,这种方法并不适合进行工程实践。本文旨在探索出一种适用于浅海波导的目标深度辨识方法,并减轻工程实践的复杂度。此方法基于Pekeris波导模型,应用了数值仿真技术对垂直双水听器声压互谱的有功分量进行了分析,发现当声源深度变化时互谱有功分量符号随之变化,这个变化规律可以用于目标深度辨识。本文总结了简正波阶数以及水听器深度变化对目标深度辨识结果的影响。通过实验验证,此方法可以较好的对浅海目标进行深度辨识,方法较为可靠,有一定的应用前景。 展开更多
关键词 pekeris波导 双水听器 目标深度辨识 声压互谱
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Depth Classification of Underwater Targets Based on Complex Acoustic Intensity of Normal Modes 被引量:3
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作者 YANG Guang YIN Jingwei +1 位作者 YU Yun SHI Zhenhua 《Journal of Ocean University of China》 SCIE CAS 2016年第2期241-246,共6页
In order to solve the problem of depth classification of the underwater target in a very low frequency acoustic field, the active component of cross spectra of particle pressure and horizontal velocity (ACCSPPHV) is... In order to solve the problem of depth classification of the underwater target in a very low frequency acoustic field, the active component of cross spectra of particle pressure and horizontal velocity (ACCSPPHV) is adopted to distinguish the surface vessel and the underwater target. According to the effective depth of a Pekeris waveguide, the placing depth forecasting equations of passive vertical double vector hydrophones are proposed. Numerical examples show that when the sum of depths of two hydro- phones is the effective depth, the sign distribution of ACCSPPHV has nothing to do with horizontal distance; in addition, the sum of the first critical surface and the second critical surface is equal to the effective depth. By setting the first critical surface less than the difference between the effective water depth and the actual water depth, that is, the second critical surface is greater than the actual depth, the three positive and negative regions of the whole ocean volume are equivalent to two positive and negative regions and therefore the depth classification of the underwater target is obtained. Besides, when the 20 m water depth is taken as the first critical surface in the simulation of underwater targets (40 Hz, 50 Hz, and 60 Hz respectively), the effectiveness of the algorithm and the cor- reemess of relevant conclusions are verified, and the analysis of the corresponding forecasting performance is conducted. 展开更多
关键词 the placing depth forecasting equations the effective depth depth classification pekeris waveguide
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船舶三维声弹性计算法研究
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作者 王方杰 《舰船科学技术》 北大核心 2016年第11X期7-9,共3页
船舶本身和水介质声弹之间的耦合会产生振动,成为影响船舶航行的水下辐射噪声之一。通过研究船舶三维声弹性可以有效的预报船舶在海洋环境中的噪声,能够加快声隐身问题的研究。本文利用近似Green函数,在Pekeris声波导模型的基础上计算... 船舶本身和水介质声弹之间的耦合会产生振动,成为影响船舶航行的水下辐射噪声之一。通过研究船舶三维声弹性可以有效的预报船舶在海洋环境中的噪声,能够加快声隐身问题的研究。本文利用近似Green函数,在Pekeris声波导模型的基础上计算有限水深中的船舶三维声弹性,在计算过程中简化了Green函数,加快了计算效率和提高了收敛性。 展开更多
关键词 近似Green函数 三维声弹性 pekeris声波导模型
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Approximate Bound State Solutions of DKP Equation for Any J State in the Presence of Woods-Saxon Potential
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作者 R.Oudi S.Hassanabadi +1 位作者 A.A.Rajabi H.Hasanabadi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第1期15-18,共4页
We study Duffin-Kemmer-Petiau(DKP) equation in the presence of the Woods-Saxon potential and obtain eigenvalues and corresponding eigenfunctions for any J state by using of the Nikiforov-Uvarov(NU) method.The Pekeris ... We study Duffin-Kemmer-Petiau(DKP) equation in the presence of the Woods-Saxon potential and obtain eigenvalues and corresponding eigenfunctions for any J state by using of the Nikiforov-Uvarov(NU) method.The Pekeris approximation is used to deal with centrifugal term. 展开更多
关键词 DKP equation Woods-Saxson potential pekeris approximation NU method
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The rotating Morse potential energy eigenvalues solved by using the analytical transfer matrix method
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作者 何英 陶求功 杨艳芳 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第10期73-78,共6页
We study the eigenvalues of the rotating Morse potential by using the quantization condition from the analytical transfer matrix(ATM) method.A hierarchy of supersymmetric partner potentials is obtained with Pekeris ... We study the eigenvalues of the rotating Morse potential by using the quantization condition from the analytical transfer matrix(ATM) method.A hierarchy of supersymmetric partner potentials is obtained with Pekeris approximation,which can be used to calculate the energies of higher rotational states from the energies of lower states.The energies of rotational states of the hydrogen molecule are calculated by the ATM condition,and comparison of the results with those from the hypervirial perturbation method reveals that the accuracy of the approximate expression of Pekeris for the eigenvalues of the rotating Morse potential can be improved substantially in the framework of supersymmetric quantum mechanics. 展开更多
关键词 rotating Morse potential analytical transfer matrix(ATM) pekeris approximation supersymmetry quantum mechanics(SUSY QM)
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水下甚低频目标的深度分类及布放预报 被引量:1
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作者 杨光 殷敬伟 +1 位作者 余赟 郭龙祥 《华中科技大学学报(自然科学版)》 EI CAS CSCD 北大核心 2015年第6期71-75,共5页
基于水下目标在甚低频段(10~100 Hz)其主要声学特征较为明显的现状,采用声压水平振速互谱的有功分量(PHVCA)进行了水面船和水下目标的区分.基于Pekeris波导模型,提出了被动垂直双矢量水听器的深度布放预报公式,用于指导双矢量水听... 基于水下目标在甚低频段(10~100 Hz)其主要声学特征较为明显的现状,采用声压水平振速互谱的有功分量(PHVCA)进行了水面船和水下目标的区分.基于Pekeris波导模型,提出了被动垂直双矢量水听器的深度布放预报公式,用于指导双矢量水听器的实际布放.通过公式推导及仿真分析指出:当双矢量水听器布放深度之和等于有效深度时,PHVCA的正负号分布不再随着水平距离的变化而变化;在有效深度内,整个声场的PHVCA被分为三个不同符号的水平区域(负-正-负),两临界面之和等于有效深度,若第一临界面小于有效深度与实际水深之差,则第二临界面大于实际水深,从而实现水下目标的深度分类.仿真验证了该算法及布放深度预报公式的有效性. 展开更多
关键词 水下目标 甚低频 简正波 互谱 pekeris波导 有效深度 深度分类
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A modified warping operator based on BDRM theory in homogeneous shallow water 被引量:6
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作者 NIU HaiQiang ZHANG RenHe LI ZhengLin 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2014年第3期424-432,共9页
In this paper,a modified warping operator for homogeneous shallow water based on the Beam-Displacement Ray-Mode(BDRM)theory is presented.According to the BDRM theory,the contribution of the beam displacement and the t... In this paper,a modified warping operator for homogeneous shallow water based on the Beam-Displacement Ray-Mode(BDRM)theory is presented.According to the BDRM theory,the contribution of the beam displacement and the time delay to the group velocity can be easily considered in a shallow water waveguide.A more accurate dispersion formula is derived by using the cycle distance formula to calculate the group velocity of normal modes.The derived dispersion formula can be applied to the homogeneous shallow water waveguide.Theoretically,the formula is related to the phase of the reflection coefficient and suitable for various bottom models.Furthermore,based on the derived dispersion relation,the modified warping operator is developed to obtain linear modal structures.For the Pekeris model,the formulae for the phase of the reflection coefficient are derived in this work.By taking account of the effect of the bottom attenuation on the reflection coefficient,the formula for the phase of the reflection coefficient including the bottom attenuation is obtained for the Pekeris model with a lossy bottom.Performance and accuracy of different formulae are evaluated and compared.The numerical simulations indicate that the derived dispersion formulae and the modified warping operator are more accurate. 展开更多
关键词 warping operator pekeris unitary operator dispersion relation BDRM theory
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