摘要
针对自由场和界面附近球壳目标回波传播路径问题,采用弹性球壳声散射简正级数解和有限元仿真结果结合频域间接法,求解自由场和半浸没状态下球壳多基地回波时域曲线。利用围线积分方法获得浸没水中球壳以及真空中球壳环绕波的相速度和群速度频散曲线。分析在平面波入射条件下,自由场和半浸没状态下球壳反对称波的传播路径,给出两种状态下的球壳收发分置回波到达时刻估计公式。分析入射信号频率以及球壳厚度对自由场中球壳回波的影响。结果表明,对于自由场中的球壳,当入射信号频率在吻合频率附近时,回波中的反对称波幅度较大;随着球壳厚度增加,厚球壳的回波趋于实心球情况,且从极薄壳中的反向回波中可以观察到由s_(0)波引起的等间隔回波。球壳半浸没状态下的回波比自由场中的回波更加复杂。研究结果对自由场和界面附近目标识别具有一定参考价值。
Aiming at the issue of echo propagation paths for spherical shell targets in free-field and near-interface scenarios,a method combining the simplified series solutions of elastic spherical shell acoustic scattering and finite element simulation with frequency domain indirect method was proposed and employed to solve the time-domain curves of bistatic echoes from spherical shells in free-field and semi-exposed states.The phase velocity and group velocity dispersion curves of surrounding waves for spherical shells submerged in water and in vacuum were obtained using the contour integral method.The propagation paths of anti-symmetric waves for spherical shells in free-field and semi-exposed states under plane wave incident conditions were analyzed,and estimation formulas for the arrival times of bistatic echoes from spherical shells in these two states were provided.The impact of incident signal frequency and spherical shell thickness on spherical shell echoes in the free-field was also analyzed.The results indicate that for spherical shells in a free-field environment,when the frequency of the incident signal is near the resonant frequency,the amplitude of anti-symmetric waves in the echoes is larger.As the thickness of the spherical shell increases,the echoes of thick shells tend to resemble to those of solid spheres.In extremely thin shells,reverse echoes caused by s_(0) waves can be observed in equally spaced intervals.The echoes in the semiexposed state of the spherical shell are more complex compared to those in the free-field environment.The findings of research have a certain reference value for target identification in free-field and near-interface scenarios.
作者
王重凯
彭子龙
周富霖
彭绍康
WANG Zhongkai;PENG Zilong;ZHOU Fulin;PENG Shaokang(School of Energy and Power,Jiangsu University of Science and Technology,Zhenjiang 212100,Jiangsu,China;Key Laboratory of Marine Intelligent Equipment and System,Ministry of Education,Shanghai Jiaotong University,Shanghai 200240,China)
出处
《噪声与振动控制》
北大核心
2025年第5期26-33,共8页
Noise and Vibration Control
基金
国家自然科学基金资助项目(52201397)
江苏省研究生科研与实践创新计划资助项目(SJCX23_2215)。
关键词
振动与波
半浸没
球壳
频散曲线
时域回波
多基地
vibration and wave
semi-exposed
spherical shell
dispersion curve
time domain waveforms
bistatic configuration
