Porous media: A faster numerical simulation method applicable to real urban communities

Abstract

The rapid development of cities worldwide and the expansion of a global economy have rendered climate change one of mankind's most severe challenges. The built environment has become a major focus for research into ways to reduce the climate effects of urban areas. Researchers who seek to model the performance of a large group of buildings, however, have available only complex simulation methods that require a massive amount of calculation if applied within an ordinary computer environment. Finding a simpler, more efficient modeling process would be a valuable contribution. This study selects a typical residential community as the simulation object, assigning boundary conditions derived from field measurements. A method of numerical simulation that treats buildings as porous media is applied to the area to simulate wind conditions. Results of the porous media method are compared with results from standard computational fluid dynamics (CFD) methods. Modeling results of the porous media method also are validated against physically measured data. Both validation methods indicate that the porous media method produces reliable results at a higher simulation efficiency. Compared with standard CFD method, in this study, the porous media method reduces the number of meshing grids by 27.8%, reduces the total iteration steps by 52.2% and reduces the total computational time by 66.7%. The porous media method is applicable to large-scale construction and intensive modeling, where it can effectively predict the wind environment at the initial planning stage.