A Stochastic Approach To The Diffusion Equation
Price
Free (open access)
Transaction
Volume
47
Pages
9
Published
2001
Size
598 kb
Paper DOI
10.2495/AIR010121
Copyright
WIT Press
Author(s)
B. Spagnolo & P. Barrera
Abstract
We propose a stochastic differential equation for the pollutant concentra- tion. This equation models the advection-diffusion equation of air pollution in the atmosphere. We obtain exact solution for the mean concentration and its standard deviation in three dimensional case. We give also the general expression of the higher moments of th^ concentration. As particular cases we obtain the exact steady state solution for neutral atmosphere conditions and for weak wind. 1 Introduction The dispersion of pollutants in the atmosphere is usually described by the diffusion equation which reads [1] c)c & c9c r/c 0 / cVc\ ^ /^ ^^A , ^ ^ ^^ /i —+ ^. — 4-r —4-^;— ^ — Dr
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