间歇性大气湍流中光传播问题的近Gauss极限分析  

Near Gaussian approximation for light propagation in the intermittent atmospheric turbulence

作　　者：陈京元[1] 陈式刚[2] 王光瑞[2] 

机构地区：[1]中国工程物理研究院北京研究生部,北京100088 [2]北京应用物理与计算数学研究所,北京100088

出　　处：《物理学报》2005年第7期3123-3131,共9页Acta Physica Sinica

基　　金：国家重点基础研究专项经费;国家自然科学基金(批准号:10147201;10247003);激光技术创新基金(批准号:20030512);国家自然科学基金重点项目(批准号:10335010);中国工程物理研究院科学技术基金(批准号:200404430)资助的课题.~~

摘　　要：间歇性是湍流的重要特征,多年来一直是湍流研究的核心内容之一.考虑大气湍流中的光传播问题,一般回避其间歇性,假设大气介电起伏满足Gauss统计.考虑大气湍流(内)间歇性对光波传播的影响.考虑到大气介电起伏方差较小的事实,将光场统计矩方程在Gauss场附近展开到四阶累计量,分析其近似解.进一步,以层次结构模型为基础,着重研究了光场二阶统计矩的间歇性效应.研究表明,大气湍流间歇性对光场的影响很小.Intermittency is an essential property of turbulent atmosphere, and is one of the core content in modern turbulence theory. But, when we consider the problem of wave propagation in turbulent atmosphere, we always evade this property and use the assumption of a Gaussian probability distribution of dielectric permittivity fluctuation. In this paper, we discussed the intermittent effects on light propagation in turbulent atmosphere. According to the fact that the variance of dielectric permittivity fluctuation is very small, we explicitly expanded the equations of optical statistical moments to the fourth-order cumulant functions and considered their solutions. As for the second-order moment which is important in optical applications, we have analyzed it emphatically by the hierarchical structures model. Our results indicate that the optical effects of turbulent intermittency are negligible and the conventional Gaussian assumption is rational.

关 键 词：大气湍流 间歇性 光传播 极限分析 Gauss场 层次结构模型 四阶累计量 核心内容 光波传播 矩方程 光场 近似解 统计矩 起伏 介电 方差 二阶 

分 类 号：O431[机械工程—光学工程]