利用湍流池模拟大气对流边界层的光传输,同时测量了到达角起伏和光路上的温度脉动。结果表明,在混合层的上部,对数温度谱偏陡,和大气中的观测结果一致,到达角起伏谱也偏陡,但到达角起伏谱曲线反映了湍流在小尺度范围内具有各向同性的特征,此时利用温度脉动方法得到的折射率结构常数小;当边界层顶部逆温层消失,发展为完全对流状态时,温度谱幂率等于"-5/3",到达角起伏谱幂率等于"-8/3",两种方法测量得到的折射率结构常数一致。

With the help of the turbulent cell, an experiment is carried out to simulate light propagation in atmospheric convective boundary layer. At the same time, fluctuation of arrival angle and fluctuation of temperature are sampled. The results show, in the upper mixed layer, the logarithmic temperature spectrum becomes more steeper than “-5/3” in the frequency range f>0.1 Hz (It accords with the fact of atmospheric boundary layer), and the logarithmic arrival angle spectrum becomes more steeper than “-8/3”, C 2 n obtained by means of temperature fluctuation is lower than by means of arrival angle. When the inversion disappears, the temperature spectrum follows the inertial sub range “-5/3 law”, and the power of arrival angle spectrum is “-8/3”, C 2 n calculated by two methods is same.