摘要
本文给出了平稳、均匀湍流中平衡涡度及非平衡涡度偏差的定义,建立了Euler及Lagra-nge湍流的随机动力微分方程,解出了各自相关函数。在各向同性及冻结湍流假设中使用Bla-ton公式按上述相关函数解出了Langrange时间尺度与Euler尺度比的表达式,其渐近值恰为全方向湍流度的倒数的1/2^(1/2)倍即0.71/i。
In this paper the 'Bernoulli's Equilibrium Vorticity' and the 'Deviation of the BEV' are defined and a random dynamic model, which can give both Lagrangian and Eulerian autocorrelation functions, are set up for wind velocity fluctuations in the stationary, homogeneous turbulence. Under Taylor's hypothesis of 'frizened eddies', the ratio of Lagrangian time scale to Eulerian is given as a function of the deviation of wind diraction, that has asymptotic form 0.71/i where i is the intensity of the turbulence, if the turbulence is isotropic.
出处
《气象学报》
CSCD
北大核心
1992年第2期140-151,共12页
Acta Meteorologica Sinica
