Classification of Turbulent Diffusions in the Atmosphere

[摘要] Turbulent diffusions of matter (gas, minute particles or heat) emitted from a point source are classified into the following four types, and interrelations among them are discussed: (1) the instantaneous source type, (2) the continuous fixed source type in a fluid flow, (3) the continuous fixed source type in a fluid at rest (4) the continuous floating source type. As an extension of this research, the turbulent diffusion of matter from a body source in an isotropic turbulent field is discussed in the latter part of this paper. Furthermore, some remarks are made on the interrelation between the so-called Eulerian and Lagrangian correlation functions, and the equation expressing the wind velocity profile near the ground is derived by making use of the Lagrangian correlation.

[学科分类] 大气科学