Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093-0238, USA.
J Acoust Soc Am. 2012 Aug;132(2):700-8. doi: 10.1121/1.4730887.
The role of surface active materials in the sea surface microlayer on the production of underwater noise by breaking waves is considered. Wave noise is assumed to be generated by bubbles formed within actively breaking whitecaps, driven into breathing mode oscillation at the moment of their formation by non-equilibrium, surface tension forces. Two significant effects associated with surface tension are identified-a reduction in low frequency noise (<1000 Hz) due to the re-fragmentation of actively radiating bubbles by fluid turbulence within the whitecap and a reduction in overall noise level due to a decrease in the excitation amplitude of bubbles associated with reduced surface tension. The impact of the latter effect on the accuracy of Weather Observations Through Ambient Noise estimates of wind speed is assessed and generally found to be less than ±1 m s(-1) for wind speeds less than 10 m s(-1) and typical values of surfactant film pressure within sea slicks.
本文考虑了表面活性物质在海表面微层中对破浪产生水下噪声的作用。假设波浪噪声是由在活跃的白浪中形成的气泡产生的，这些气泡在形成时由于非平衡的表面张力而被驱动进入呼吸模式的振荡。与表面张力相关的两个显著效应被确定：由于白浪中流体湍流使主动辐射的气泡重新破碎，低频噪声（<1000Hz）降低；由于与表面张力降低相关的气泡激励幅度减小，总噪声水平降低。后者对风速通过环境噪声估计的精度的影响进行了评估，结果发现，对于风速小于 10m/s 且海油膜内典型的表面活性剂膜压力的情况，其影响一般小于±1m/s。
