光学学报, 2014, 34 (6): 0601001, 网络出版: 2014-04-29
近地面层大气非Kolmogorov湍流特征参数测量
Measurement of Non-Kolmogorov Turbulence Characteristic Parameter in Atmospheric Surface Layer
大气光学 非Kolmogorov湍流 谱幂率 广义结构常数 等效结构常数 atmospheric optics non-Kolmogorov turbulence power law of spectrum generalized structure parameter equivalence structure parameter
摘要
分析了2011年1月13日至17日超声气温时间序列数据,不仅采用结构函数和谱分析方法得到了Kolmogorov结构常数C2n,而且提出了非Kolmogorov湍流特征参数测量方法,获得了非Kolmogorov谱幂率α、广义折射率结构常数2n以及等效折射率结构常数2n等测量结果。结论如下:1)实验期间一维温度谱幂率在-1.9<-α1<-1.5范围内的频数为77.9%,弱湍流时谱幂率与Kolmogorov-5/3谱相比偏平;2)单点温度结构函数法和单点温度频谱法测量C2n差别不大;3) C2n和2n量级和变化趋势基本一致,差别主要体现在弱湍流时C2n比2n小,往往发生在谱幂率偏平的时段;4) 2n与2n量级和变化趋势基本一致,差别主要体现在2n有一些起伏,且与给定波长λ和传输路径长度L的选取有关。
Abstract
The time series of sonic temperature on 13 to 17 January 2011 are analysed. Not only the classical Kolmogorov structure parameter C2n is obtained with method of structure function and spectrum analysis,but also the non-Kolmogorov turbulence characteristic parameters such as non-Kolmogorov power law α, generalized structure parameter 2n, equivalence structure parameter 2n are measured.Based on the experimental results, it can be seen as follows. 1) The frequency of power law of the one-dimensional non-Kolmogorov spectrum that range is -1.9<-α1<-1.5 is 77.9%. The -α1 under weak turbulence is more flat than Kolmogorov -5/3 law spectrum. 2) The C2n values derived from structure function analysis and spectrum analysis are slightly difference. 3) The trend and order of magnitude agrees well between C2n and 2n, and the discrepancy is that C2n can be smaller than 2n when weak turbulence occurs, in that moment the power spectrum is usually flatter than the -5/3 Kolmogorov theory. 4) The trend and order of magnitude agrees well between 2n and 2n, and the discrepancy is that 2n has a little fluctuant, and can change according to different values of wavelength and propogation length.
吴晓庆, 黄印博, 梅海平, 邵士勇, 黄宏华, 钱仙妹, 崔朝龙. 近地面层大气非Kolmogorov湍流特征参数测量[J]. 光学学报, 2014, 34(6): 0601001. Wu Xiaoqing, Huang Yinbo, Mei Haiping, Shao Shiyong, Huang Honghua, Qian Xianmei, Cui Chaolong. Measurement of Non-Kolmogorov Turbulence Characteristic Parameter in Atmospheric Surface Layer[J]. Acta Optica Sinica, 2014, 34(6): 0601001.