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The advection-Diffusion Equation in three dimensions was solved using the Separation variable, Substitution and Laplace transform methods, taking into account that eddy diffusivity along the horizontal, lateral coordinates and wind velocity are constant respectively, while the vertical eddy diffusivity is a function of the vertical height z, Monin-Obukhov length L friction velocity at different emission rate and operation of iodine (I-131) in an unstable condition. We took the measured data from Inshas, Cairo, Egypt and compared the concentration of the calculated results with the results obtained from the solution equation at heights of 0.7, 27, and 43 meters. We found that all models are within a factor of two with the observed data from statistical evaluations in unstable conditions, we found that all models fell into a factor of two with the observed data. Whereas with NMSE and FB, the current models correlate better with the observed data. [ABSTRACT FROM AUTHOR]

Three‐dimensional advection–diffusion equation with steady state was evaluated from continuous point source taking the vertical and crosswind eddy diffusivities as power law of vertical height and downwind distance with constant wind speed to get the concentration in three dimensions. Separation of variables technique and Hankel transform were used to calculate this equation. The proposed analytical solution was compared with diffusion experiment of radioactive Iodine‐135 (I135) in unstable condition at Inshas, Cairo, Egypt. A good agreement achieved between calculated and observed concentration support our proposed model. [ABSTRACT FROM AUTHOR]

Hankel transform was employed to solve the two-dimensional steady state advection–diffusion equation considering a continuous point source with vertical eddy diffusivity as a power law of vertical height and downwind distance, also, taking wind speed as power law. The analytical model was evaluated and compared with Hanford diffusion experiment in stable conditions and Copenhagen diffusion experiment in unstable and neutral conditions which was done by reducing the general analytical model to a one with linear vertical eddy diffusivity and constant downwind speed profile. Comparison with other analytical models was held. The presented model predictions show a good agreement with observations and lay inside a factor of two with observed data of both Hanford and Copenhagen diffusion experiments. [ABSTRACT FROM AUTHOR]

The investigated work aims to calculate the concentration of different isotopes through short downwind distances. A theoretical model was designed to calculate the isotope concentration in the wind. The mathematical calculation depends on wind speed, decay distance and the dilution factor to get the concentration of isotopes (131I, 133I, 135I and 137Cs) detected in wind at different distances from a nuclear power station. There is a good agreement between the calculated and observed concentrations of 131I, 133I, 135I and 137Cs. [ABSTRACT FROM AUTHOR]

A short range model calculating ground-level concentration from elevated sources is estimated, which realized a Fickian-type formula, taking the source and mixing height as functions of the wind velocity and eddy diffusivity profiles. The model estimated with an exact solution of the advection diffusion equation as compared with experimental ground level concentrations using meteorological data collected near the ground. [ABSTRACT FROM AUTHOR]

The wind characteristic for six stations, on the Red Sea and Sinai coasts in Egypt, are analyzed for power generation. The Weibull parameters are determined by two methods. the best locations are El-Tur, Hurghada and Zafarana, where annual average wind speed at 10m are greater than 4.5m/s. [ABSTRACT FROM AUTHOR]