Mixing processes in a nocturnal low-level jet : An LES study
Mixing processes in a nocturnal low-level jet : An LES study
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夜间低空急流的混合过程：LES 研究
DOI：
10.1175/jas3903.1
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发表时间：
2007
影响因子：
3.1
通讯作者：
M. A. Jiménez
中科院分区：
文献类型：
--
作者：
J. Cuxart;M. A. Jiménez
摘要利用大涡模拟模式模拟了1998年西班牙稳定大气边界层试验（SABLES-98）中观测到的一个定常低空急流。辐射被考虑在内，因为它的贡献的预算的趋势的温度是一样重要的贡献的湍流在表面层。由此产生的制度是一个两层的流动分离的温度梯度的变化在最大速度的水平。上部具有由剪切产生产生的湍流，其延伸到最大风高度的3倍，并且与下面的层具有相同的数量级。模型将喷流头部视为一个解耦层，使用被动标量可以检查穿过它的运输量，这是非常小的。下层对地面边界条件非常敏感，但上层的主要模式没有明显变化。运行比较的意见通过…
Abstract A steady-state low-level jet observed in the Stable Atmospheric Boundary Layer Experiment in Spain-1998 (SABLES-98) campaign is simulated using a large-eddy simulation model. The radiation is taken into account since its contribution to the budget of the tendency of temperature is as important as the contribution of the turbulence in the surface layer. The resulting regime is a two-layer flow separated by a change of the temperature gradient at the level of maximum speed. The upper part has turbulence originated by shear production extending up to 3 times the height of wind maximum and of the same order of magnitude as in the layer below. The jet nose is seen by the model as a decoupling layer, and the use of passive scalars allows for the inspection of the amount of transport across it, which is very small. The lower layer is very sensitive to the surface boundary conditions, but the principal patterns in the upper layer do not change significantly. The runs are compared to the observations thro...