Evidence of Mixed Scaling for Mean Profile Similarity in the Stable Atmospheric Surface Layer
Evidence of Mixed Scaling for Mean Profile Similarity in the Stable Atmospheric Surface Layer
复制标题
稳定大气表层平均剖面相似性混合标度的证据
DOI：
10.1175/jas-d-22-0260.1
复制
发表时间：
2023
影响因子：
3.1
通讯作者：
Chamecki, Marcelo
中科院分区：
文献类型：
--
作者：
Heisel, Michael;Chamecki, Marcelo
本文提出了一个新的混合标度参数z =z/(Lh)1/2来表示稳定大气表层的相似度，其中z =高度，Lis为奥布霍夫长度，his为边界层深度。与Monin-Obukhov相似理论（MOST）的参数ζ=z/ l相比，新参数z提高了大涡模拟中风速和气温的平均廓线相似度。它还为CASES-99现场测量提供了相同的线性相似关系，包括在观察到与MOST有很大偏差的强稳定（但仍然湍流）状态下。结果进一步表明，湍流能量耗散率的相似性取决于两者。提出的混合尺度和相关性可以用与近地表渐近达到的无z分层极限有关的物理参数来解释。所提出的证据和拟合的相似关系是有希望的，但结果和论点仅限于理想平稳稳定边界层的小样本。需要来自独立数据集和分析的佐证，包括本文未测试的复杂和瞬态条件。
A new mixed scaling parameterZ=z/(Lh)1/2is proposed for similarity in the stable atmospheric surface layer, wherezis the height,Lis the Obukhov length, andhis the boundary layer depth. In comparison with the parameterζ=z/Lfrom Monin–Obukhov similarity theory (MOST), the new parameterZleads to improved mean profile similarity for wind speed and air temperature in large-eddy simulations. It also yields the same linear similarity relation for CASES-99 field measurements, including in the strongly stable (but still turbulent) regime where large deviations from MOST are observed. Results further suggest that similarity for turbulent energy dissipation rate depends on bothZandζ. The proposed mixed scaling ofZand relevance ofhcan be explained by physical arguments related to the limit ofz-less stratification that is reached asymptotically above the surface layer. The presented evidence and fitted similarity relations are promising, but the results and arguments are limited to a small sample of idealized stationary stable boundary layers. Corroboration is needed from independent datasets and analyses, including for complex and transient conditions not tested here.