Keywords: atmospheric dispersion, circular cylinder, wake, model evaluation, concentration fluctuations, laterally displaced sources, computational fluid dynamics, CFD, dispersion modelling, atmospheric flow, cylindrical obstacles, ammonia, propane
Modelling of atmospheric flow and dispersion in the wake of a cylindrical obstacle
The computational fluid dynamics code ADREA–HF is used to simulate atmospheric dispersion field experiments around an isolated cylindrical obstacle and two upwind sources of ammonia and propane, with the ammonia source located at different lateral positions. Model calculated concentrations and concentration fluctuations are compared with the experimental results, to investigate the effect of the lateral source displacement on the fluctuations intensity, showing a fair level of agreement. The observed differences were mainly attributed to the specificities of the cases, such as the interaction of a laterally displaced plume with the cylindrical obstacle, and to the variability observed in the field.