Numerical study of the dispersion of the pollutant (CH4) in a canopy urban [Etude numérique de la dispersion du polluant (CH4) dans une canopée urbaine]

The present work is about the study of pollution dispersion (ch4) in urban site consists of street canyons. several numerical simulations were performed using the chensi code. the flow is considered three-dimensional,turbulent. the aim is to explain the experimental data obtained by atmospheric wind on the physical model. the site company of mock urban setting test must be selected to be simulated by the chensi code developed by the dynamic team atmospheric inhabited (central school of nantes,france). numerical results presented in this study in the mean flow field,the concentration field of the passive scalar in one direction of wind incidence (-45° from street axes). for an objective comparison of the chensi model performances within other european codes used for must configuration simulation. for the direction of the wind incidence (-45°),an analysis showed that the results for the mean concentration field was in good agreement within the ones obtained experimentally.