SINOPSIS

A theoretical study was developed to obtain solutions of the atmospheric diffusion equation for various point sources, considering radioactive decay and axial diffusion, under neutral atmospheric conditions. An algebraic turbulence model available in the literature, based on the Monin—Obukhov similarity theory, was used to represent the turbulent transport in the vertical direction; in the longitudinal directions a constant mass eddy diffusivity was considered. The bidimensional transient partial differential equation, representative of the physical phenomena, was transformed into a coupled one-dimensional transient equation system by applying the generalized integral transform technique (GITT).The coupled system was solved numerically using a subroutine based on the lines method. In order to evaluate the computational algorithm, some representative physical situations were analyzed.