近海混浊水的附加声衰减研究——实验测量值与考虑粒径分布的理论估算值的比较

Additional acoustic attenuation of coastal turbid water——Measurements compared with predictions using particle sizing distributions

对黏滞吸收的估算分析表明,悬浮物黏滞吸收受粒径影响显著。基于混响法,本文实验测量了泥沙含量0.2～2.0 kg/m^3之间的混浊海水和玻璃珠混浊水的黏滞吸收,结果表明实验测量值与考虑粒径分布的理论估算值具有更好的一致性。在实验频段内,泥沙含量为1.0 kg/m^3时,采用粒径分布的理论估算值与采用平均粒径的理论估算值相比,悬浮物的黏滞吸收每100 m相差2.3～2.6 dB。在近海混浊水声衰减的估算中,悬浮物的黏滞吸收必须考虑粒径分布。

The prediction results showed that the viscous absorption of suspended particles is affected by suspended particle size. Based on reverberation method, the viscous absorption of 0.2 ～2.0 kg/m^3 sediment and glass bead turbid seawater was measured. It is shown that the measurement results were more consistent with the prediction results using particle size distributions. By comparison of the prediction results using particle size distributions with that using average particle radius, it was that the discrepancy is 2.3 ～2.6 dB every 100 meters for 1.0 kg/m^3 of sediment turbid seawater in the scope of experimental frequency. It was suggested that the particle size distributions must be used in the predictions of viscous absorption in coastal turbid water.