The Mechanics and Acoustics of Bubbles Fragmenting in Sheared Flow.

剪切流中气泡破碎的力学和声学。

• 批准号: 0727140
• 负责人: Grant Deane
• 金额: $ 51.8万
• 依托单位: University of California-San Diego Scripps Inst of Oceanography
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-01 至 2011-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0727140&HistoricalAwards=false
• 关键词: Mechanics; Acoustics; Bubbles; Fragmenting; Sheared

Wave-induced bubbles in the upper ocean drive a number of important oceanographic processes including air-sea gas fluxes, aerosol production and the scavenging of organic surfactants. The medium to large bubbles that persist for just a few seconds in the upper ocean during and immediately after wave breaking are thought to play a dominant role in the transport of carbon dioxide. Because it is difficult, for technological and logistical reasons, to make these measurements, there are very few data sets that characterize bubble distributions within whitecaps. Scientists at the Scripps Institution of Oceanography will conduct an experiment whereby bubbles in a turbulent fluid of various sizes will be fragmented. As the bubbles fragment they emit an acoustic signal that will be recorded with hydrophones. In addition, two cameras will record the details of the bubble breakup. The ultimate goal of the research is to determine bubble creation rates at the ocean surface. Although noise is known to come from bubbles as they form, the mechanisms that determine the amount of energy associated with the acoustic oscillations is not yet known. If it were, this work could lead to the development of a tool that allows one to measure bubble creation rates based upon ambient noise measurements. The experiment and data analysis will include the participation of an undergraduate intern.

波浪诱导的上海洋驱动了许多重要的海洋学过程，包括气海气通量，气溶胶产生和有机表面活性剂的清除。在波浪破裂期间和爆发后立即在上海中持续几秒钟的中等气泡在二氧化碳的运输中起主要作用。因为出于技术和后勤原因很难进行这些测量，所以很少有数据集表征白ecaps中的气泡分布。 Scripps海洋学研究所的科学家将进行一个实验，从而使各种尺寸的湍流中的气泡分散。作为气泡碎片，它们会发出一个声信号，该信号将用言语记录。此外，两个相机将记录泡沫破裂的细节。该研究的最终目标是确定海面的气泡创造率。尽管已知噪声来自气泡，但尚不清楚确定与声学振荡相关的能量量的机制。如果是这样，这项工作可能会导致工具的开发，该工具允许人们根据环境噪声测量值测量气泡创建率。实验和数据分析将包括本科实习生的参与。