investigation of dissipation flow in the urban canyon

In regard to wind flow in the cities, obtaining a minimal level of pollution in the environment is achievable. different policies have been considered for minimizing urban pollution such as the attachment and/or reduction of building parts like airtraps, ceiling forms, and so on. due to an increase in population in cities and an increasing need for housing, the construction of high-rise buildings is inevitable. people are forced to live in high-rise buildings to meet their housing needs and from lack of urban open spaces. a cfd based software, envi-met, is used to acquire knowledge concerning the air pollution surrounding the buildings. in this case, we can approximate that an angle of 30 degrees, in regard to an urban canyon, is the best angle to dissipate pollution. also, in an ideal case with imposed changes in the form, we could reduce the problem by better navigation of inside wind of urban canyons into spaces between blocks of buildings that have the capacity to trap the particles. finally, it is found that we may be able to have more optimal results for the dissipation of pollutants by suitable orientation of blocks in regard to the wind flow.