湍流大气中水平风速模涨落的相关
ON THE CORRELATION OF WIND SPEED FLUCTUATION IN THE TURBULENT ATMOSPHERE
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摘要: 推导出湍流度不大时,水平风速模涨落的相关,方差等量与分量风速涨落相应量联系的近似式.計算表明,在大气湍流微結构研究通常遇到的湍流度下,模量的相关与順风分量相关差不多.說明了小尺度大气湍流中,风速模涨落的空間相关也可以近似地以时間相关来代替.討論了推导时引入的附加条件在大气中的合理性.Abstract: When the gustness is small, the standard deviation and correlation function togethen with structure function of wind speed fluctuations may be expressed in terms of horizontal eddy components to a moderate degree of approximation and further the time correlation of wind speed fluctuations may be used instead of space correlation. In case of gustness usually occured in the atmosphere, the computed correlations of wind speed fluctuations by the expression given by the anther are is good agreement with the observed values of correlations of eddy component along the mean direction based on the data given by H. A. Panofsky and H. E. Cramer. The validity of the basic assumptions introduced by the anther in computing various expression has also been discussed briefly from the point of view of atmospheric turbulence.