大气边界层中湍流扩散问题的随机微分方程处理

PROCESSING THE TURBULENT DIFFUSION PROBLEM IN THE ATMOSPHERIC BOUNDARY LAYER BY USING OF STOCHA STIC DIFFERENTIAL EQUATION

摘要: 本文在对湍流扩散机理进行分析的基础上,提出用ITÔ·K随机微分方程来描述湍流扩散过程,并导出了大气边界层中连续点源扩散浓度分布的一般形式。其一级近似可以用初等函数来表示,它的特例与污染气象学中常用的模式是一致的。另外,本文所给出的一般形式还可以包容地转风和重力沉降等作用对扩散的影响,并具体给出了它的一级近似表达式。

Abstract: On the basis of physical mechanics of the turbulent diffusion, the turbulent diffusion process has been described with Ito's stochastic differential equation, and the concentration model of the continous point source has been obtained. Its first order approximate solution has been expressed as a form of analytical function. The special cases of the first order approximate solution has been identified with the form which has been commonly used. The solution includes the factors of geostrophic wind, gravity deposit and etc., which influence the diffusion process certainly.

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