摘要
从实验和理论上研究了充水有限长圆柱薄壳的声散射。实验采用指向性尖锐的宽带收发合置换能器,发射宽带调频信号和单频窄脉冲信号进行测量,所得结果分别在时域和频域上与理论计算结果相对比,证明其吻合程度很好。理论和实验的结果表明,内部充水圆柱壳在频域上增加了一组由内部流体负载引起的附加波的共振;而在时域上增加了一系列由于声波在壳体内来回反射产生的"回音廊"式回波。频率-角度图中"碗"形亮线出现分簇的原因解释为前几种模式"回音廊"式回波叠加的结果。
Acoustic scattering from the submerged fluid-filled finite cylindrical shell insonified by an incident plane wave is studied experimentally and theoretically. A broadband transducer with the sharp directivity is used as both the transmitter and the receiver in the experiment. The broadband LFM signal and the single-frequency narrow pulse are used to measure the backscattering field of the cylindrical shell. The measured results have a good agreement with the theory＇s both in time and frequency domain. The theoretical and experimental results show that the resonances of several additional waves which are caused by the internal fluid are presented in the frequency domain. And a series of ＇whispering gallery＇ waves produced by the waves reflect back and forth in the internal fluid of the cylindrical shell are added. The reason for the clustering of bowl shaped resonance curves in the frequency-angle spectrum is explained as the superposition of several ＇whispering gallery＇ waves.
出处
《声学学报》
EI
CSCD
北大核心
2010年第1期31-37,共7页
Acta Acustica
基金
国家自然科学基金资助项目(105004021)
关键词
圆柱薄壳
声散射
有限长
实验
充水
脉冲信号
调频信号
计算结果
Acoustic field measurement
Experiments
Fluids
Frequency domain analysis
Resonance
Shells (structures)
