Effect of zero-mean-shear turbulence on rise velocity of in-chain bubbles from marine natural seeps
Effect of zero-mean-shear turbulence on rise velocity of in-chain bubbles from marine natural seeps
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DOI：
10.1016/j.oceaneng.2023.114810
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发表时间：
2023-07
影响因子：
5
通讯作者：
Huijie Wu;Binbin Wang;D. Di Iorio;M. Razaz
中科院分区：
文献类型：
--
作者：
Huijie Wu;Binbin Wang;D. Di Iorio;M. Razaz
本文报道了一个实验室实验，调查海洋湍流的影响气泡从自然渗漏释放的上升速度。为了模拟海底的湍流条件，我们使用了振荡网格搅拌湍流（OGT）槽产生近均匀和各向同性的湍流（HIT）与一系列的湍流耗散率。通过将零平均剪切湍流对气泡上升的影响与横流的影响隔离开来，我们发现湍流的存在使气泡上升速度在六种不同的气体流速下降低了19%。我们的数据表明，归一化气泡上升速度和归一化湍流耗散率的对数值之间的线性关系，有两个不同的斜率。我们的分析表明，湍流增加了气泡的水平运动，使它们横向分散，从而降低了它们的上升速度。最后，我们提出了一个半经验公式，可以用来计算链内气泡在湍流沃茨中的上升速度。这些发现对于我们理解湍流在海洋沃茨中渗漏气泡的运输和命运中的作用具有重要意义。
This paper reports on a laboratory experiment that investigates the impact of ocean turbulence on the rise velocity of bubbles released from natural seeps. To simulate the turbulence conditions of ocean bottoms, we used an oscillating grid-stirred turbulence (OGT) tank to generate nearly homogeneous and isotropic turbulence (HIT) with a range of turbulence dissipation rates. By isolating the effect of zero-mean-shear turbulence on the bubble rise from the effect of cross flows, we found that the presence of turbulence reduced the bubble rise velocity by up to 19% across six different gas flow rates. Our data show a linear relationship between the normalized bubble rise velocity and the log-value of the normalized turbulence dissipation rate, with two different slopes. Our analysis suggests that turbulence increased the horizontal motion of the bubbles, causing them to scatter laterally, thereby reducing their rise velocity. Lastly, we propose a semi-empirical equation that can be used to calculate the rise velocity of in-chain bubbles in turbulent waters. These findings have important implications for our understanding of the role of turbulence in the transport and fate of seep bubbles in ocean waters.