The influence of wind direction and source location in the flow pattern and concentration field over an urban canopy

Resumo

The flow characteristics and pollutant dispersion around a group of obstacles are investigated
numerically using a Reynolds stress turbulence closure model. The mathematical modeling is based on the solution
of the conservation equations (mass, momentum, and chemical species). Numerical simulations were performed
over an idealized urban canopy with twenty-four unequally spaced buildings with rectangular cross sections and
constant height with a commercial software ANSYS-FLUENT 16.0, that uses a finite volume method. The
influence of the source location was evaluated. Two different locations of the point sources were considered. Wind
direction influence was also analyzed and discussed. It was found that the flow pattern is very affected by the wind
direction, with the formation of eddies and low-velocity regions, and the mean concentration distribution was also
determined by the source location and building configuration relative to the wind.