Analyses of Isotropic and Anisotropic Turbulent Dispersion of Particles in the Atmosphere

Abstract

Analyses of the isotropic and anisotropic diffusion of clusters of fluid particles in the atmosphere are made. Lin's theory of diffusion is subjected to an observational test. The autocorrelation coefficients of the vector acceleration are computed and the value of B0 in Lin's one particle theory is found to be 3 and 5 cm2 sec−3 for two series of experiments. The mean autocorrelation coefficients of the vector relative acceleration are computed and the value of B in Lin's isotropic diffusion theory is found to be 68 and 28 cm2 sec−3 for two series of experiments. The horizontal eddy diffusivities for the isotropic diffusion process are found to range from 0.4×103 to 6.4×103 cm2 sec−1. The mean cross-covariance coefficient of the relative acceleration is computed and the value of Bij in Lin's anisotropic diffusion theory is found to be 30 cm2 sec−3. The values of the diffusion tensor for the anisotropic diffusion process are found to range from 0.3×103 to 1.8×103 cm2 sec−1.