Finite element simulation of chimney emissions: a proposal for near field impact assessment in highly complex terrains

Abstract

This work focuses in the simulation of transport and reaction of pollutant emissions from high stacks with the Finite Element Method. Nowadays tendencies on numerical modelling of punctual emission sources are analyzed. The so-called hybrid models are one of the best available options. These models simulate the pollutant evolution in the microscale, from hundreds of meters to few kilometres, with lagrangian puff models, and the urban and regional scales, few kilometres and above, with Eulerian finite differences schemes. Approximation exposed in this paper has the aim of substituting the lagrangian local treatment, source of several problems and approximating errors, with an Eulerian Finite Element approach. Simulations for highly demanding problems (from both topography and wind speed point of view) have been computed and analyzed. The results show that the approach is efficient and accurate, although some mesh adjustments has found needed for extremely windy situations.