不同频率条件下海月水母目标强度测量及分析

Measurement and Analysis for Target Strength of Jellyfish(Aurelia Aurita)at Different Frequencies

摘要:

为获得海月水母不同频率下声学特征，在水池条件下，运用鱼探仪对海月水母开展目标强度(TS) 测量实验。结果表明：伞径约为 10 cm 海月水母，姿态角在 60°~ 90°时，单频(120 kHz)条件下，目标强度测量值为–66 ~ –63 dB，接近高通液球模型；宽频(90 kHz~170 kHz)条件下，目标强度测量值为–61 ~ –59 dB， 接近 Mutlu 目标强度和伞径的关系式模型。并进一步分析了相同伞径水母目标强度测量值产生差异的原因， 研究结果将为核电站冷源致灾生物的浅海宽频探测提供参考。

Abstract:

In order to obtain the acoustic characteristics of jellyfish(Aurelia aurita)at different frequencies， the Target Strength(TS)measurement experiment is carried out on the jellyfish with an echosounder in the pool. The results show that for the jellyfish with about 10 cm umbrella diameter and 60° ~ 90° attitude angle，the measured value of the TS is –66 ~ –63 dB at a single frequency(120 kHz)，which is close to the high flux liquid sphere model， and the measured value of the TS is –61 ~ –59 dB at the broadband (90 kHz ~ 170 kHz)condition，which is close to the Mutlu relational model between TS and umbrella diameter. In addition，the reasons for the differences in the measured TS of the jellyfishes with the same umbrella diameter are analyzed. The conclusion of this thesis will provide a reference for nuclear power plants to conduct the detection of cold source disaster-causing organisms in shallow sea with a broadband echosounder.