Boundary-Layer Meteorology

, Volume 139, Issue 3, pp 501–519

Regime Diagrams for K-Theory Dispersion

Article

DOI: 10.1007/s10546-011-9594-4

Cite this article as:
Smith, R.B. Boundary-Layer Meteorol (2011) 139: 501. doi:10.1007/s10546-011-9594-4

Abstract

In atmospheric dispersion, the “non-Gaussian” effects of gravitational settling, the vertical gradient in diffusivity and the surface deposition do not enter uniformly but rather break up parameter space into several discrete regimes. Here, we describe regime diagrams that are constructed for K-theory dispersion of effluent from a surface line source in unsheared inhomogeneous turbulence, using a previously derived Fourier–Hankel method. This K-theory formulation differs from the traditional one by keeping a non-zero diffusivity at the ground. This change allows for turbulent exchange between the canopy and the atmosphere and allows new natural length scales to emerge. The axes on the regime diagrams are non-dimensional distance defined as the ratio of downwind distance to the characteristic length scale for each effect. For each value of the ratio of settling speed to the K gradient, two to four regimes are found. Concentration formulae are given for each regime. The regime diagrams allow real dispersion problems to be categorized and the validity of end-state concentration formulae to be judged.

Keywords

Deposition Diffusion Dispersion K-theory Settling Surface-layer transport 

Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  1. 1.Yale UniversityNew HavenUSA

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