...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Geophysical Research, C. Oceans: JGR >On the coefficients of small eddy and surface divergence models for the air-water gas transfer velocity
【24h】

On the coefficients of small eddy and surface divergence models for the air-water gas transfer velocity

机译：关于水-气传输速度的小涡模型和表面发散模型的系数

获取原文
获取原文并翻译 | 示例
   

获取外文期刊封面封底 >>

       
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Recent studies suggested that under low to moderate wind conditions without bubble entraining wave breaking, the air-water gas transfer velocity k~+ can be mechanistically parameterized by the nearsurface turbulence, following the small eddy model (SEM). Field measurements have supported this model in a variety of environmental forcing systems. Alternatively, surface divergence model (SDM) has also been shown to predict the gas transfer velocity across the air-water interface in laboratory settings. However, the empirically determined model coefficients (α in SEM and c_1 in SDM) scattered over a wide range. Here we present the first field measurement of the near-surface turbulence with a novel floating PIV system on Lake Michigan, which allows us to evaluate the SEM and SDM in situ in the natural environment. k~+ was derived from the CO_2 flux that was measured simultaneously with a floating gas chamber. Measured results indicate that α and c_1 are not universal constants. Regression analysis showed that a ～ log(ε) while the near-surface turbulence dissipation rate ε is approximately greater than 10~(-6) m~2 s~(-3) according to data measured for this study as well as from other published results measured in similar environments or in laboratory settings. It also showed that α scales linearly with the turbulent Reynolds number. Similarly, coefficient c_1 in the SDM was found to linearly scale with the Reynolds number. These findings suggest that larger eddies are also important parameters, and the dissipation rate in the SEM or the surface divergence β' in the SDM alone may not be adequate to determine k~+ completely.
机译：最近的研究表明，在中低风条件下没有气泡夹带波破裂的情况下，遵循小涡模型（SEM），可以通过近地表湍流对空气-水的气体传输速度k〜+进行机械参数化。现场测量已在各种环境强迫系统中支持该模型。另外，在实验室环境中，表面散度模型（SDM）也已显示出可预测穿过空气-水界面的气体传输速度。但是，凭经验确定的模型系数（SEM中的α和SDM中的c_1）分散在很宽的范围内。在这里，我们介绍了在密歇根湖上使用新型浮动PIV系统进行的近地表湍流的首次野外测量，这使我们能够在自然环境中就地评估SEM和SDM。 k〜+是从与浮动气室同时测量的CO_2通量得出的。测量结果表明，α和c_1不是通用常数。回归分析表明，根据本研究以及其他研究得出的数据，近地表湍流耗散率ε约大于10〜（-6）m〜2 s〜（-3），而α〜log（ε）更大。在类似环境或实验室环境中测量的已发布结果。它还表明，α与湍流雷诺数成线性比例关系。类似地，发现SDM中的系数c_1与雷诺数成线性比例。这些发现表明，较大的涡流也是重要的参数，而SEM中的耗散率或SDM中的表面散度β'可能不足以完全确定k〜+。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号