利用2006年湖南小墨山地区冬夏两个采样时段的湍流观测数据,对当地湍流发展混合或扰动情况进行讨论。整体湍流特征量σu,w/u*观测值与相似性函数计算值差别较大,且与来流方向无明显关系,表明当地湍流受扰动强、发展混合差。结合印痕计算进行的湍流通量观测空间代表性分析发现,当地观测结果主要代表测点周边山地和平原两种地形的情况。冬季印痕主要分布于北方平原地区,山地影响平均仅为21%,而夏季的印痕源区主要为南方的山地,约占54%。
The authors used the observed turbulence data in wintertime and summertime of 2006 in Xiaomo Mountain, Hunan Province to study the state of local turbulence. The difference between the observed σu,w/u* and the results calculated from similarity function was large, and there was not clear relationship between σu,w/u* with wind directions. It is suggested that the local turbulence was generally not developed completely and was easily disturbed. By using a footprint model, it is found that the flux measurements in Xiaomo Mountain were representative of two types of topography: plain region and hilly region. In winter, the northern plain regions played a major role in the overall footprint sources, and the contribution of hilly area only accounted for 21%. While in summer, the influence of southern hilly area was large, with the contribution of 54%.