Numerical experimentation with particles having non-zero terminal velocity in the atmospheric surface layer
Tóm tắt
Numerical solutions are obtained for a two-dimensional eddy diffusion equation describing aerosol particles in the atmospheric surface layer. Particles are assumed to be from either an elevated line source or a surface area source. Characteristics of the solutions are exhibited as a function of source type, lower boundary condition, and the ratio of terminal velocity (Ω) to friction velocity (u
*). This theory indicates that suspended particles tend to escape the near-surface layer, and are thus subject to long-range transport, when the ratio Ω/u
* is less than von Karman's constant. This prediction is consistent with available data.
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