Three-Dimensional Mode Coupling around a Conical Seamount and the Use of Random Discretization
LUO Wen-Yu1**, SCHMIDT Henrik2
1State Key Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Sciences, Beijing 100190 2Department of Mechanical Engineering, Massachusetts Institute of Technology, Massachusetts 02139, USA
Three-Dimensional Mode Coupling around a Conical Seamount and the Use of Random Discretization
LUO Wen-Yu1**, SCHMIDT Henrik2
1State Key Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Sciences, Beijing 100190 2Department of Mechanical Engineering, Massachusetts Institute of Technology, Massachusetts 02139, USA
摘要Three-dimensional mode coupling around a conical seamount in an ocean waveguide is studied. It is shown that strong mode coupling occurs at the edge of a conical seamount for the incident normal modes with significant amplitudes below the top of the seamount. Therefore, mode coupling is critical for the investigation of the acoustic field around a seamount. In addition, we suggest the use of random discretization for representing smoothly varying bathymetry. For the use of uniform discretization, when the horizontal step size is greater than half of the wavelength, artificial diffraction lobes appear due to coherent backscatter. However, by using the random discretization scheme instead, such artificial diffraction lobes are diffused, resulting in a faster convergence rate.
Abstract：Three-dimensional mode coupling around a conical seamount in an ocean waveguide is studied. It is shown that strong mode coupling occurs at the edge of a conical seamount for the incident normal modes with significant amplitudes below the top of the seamount. Therefore, mode coupling is critical for the investigation of the acoustic field around a seamount. In addition, we suggest the use of random discretization for representing smoothly varying bathymetry. For the use of uniform discretization, when the horizontal step size is greater than half of the wavelength, artificial diffraction lobes appear due to coherent backscatter. However, by using the random discretization scheme instead, such artificial diffraction lobes are diffused, resulting in a faster convergence rate.
LUO Wen-Yu**;SCHMIDT Henrik. Three-Dimensional Mode Coupling around a Conical Seamount and the Use of Random Discretization[J]. 中国物理快报, 2010, 27(11): 114302-114302.
LUO Wen-Yu**, SCHMIDT Henrik. Three-Dimensional Mode Coupling around a Conical Seamount and the Use of Random Discretization. Chin. Phys. Lett., 2010, 27(11): 114302-114302.
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2010, Vol. 27 
