Article,
Study on micro-atmospheric environment by coupling large eddy simulation with mesoscale model
JOURNAL OF WIND ENGINEERING AND INDUSTRIAL AERODYNAMICS, (August 2012)
DOI: {10.1016/j.jweia.2012.03.033}
Abstract
This paper investigates wind field and traffic pollutant dispersion at
street level in a local urban area. A coupling method is employed that
the time-varying boundary values of velocity and temperature at the
local urban area are provided by the Weather Research and Forecasting
(WRF) mesoscale model which computes the atmospheric flow over the
entire city while the atmospheric environmental flows are computed by a
large eddy simulation (LES) code developed by the authors in the local
urban area. In order to reduce the LES computation cost, a combined
model for buildings in the urban area is proposed that in a central
area, where the wind and pollution is most concerned, the buildings are
properly resolved in fine grids and non-slip flow condition is
prescribed at rigid boundaries whereas in the surrounding region the
buildings are treated as drag element and coarse grids are used in
computation. The wind field, temperature and carbon monoxide
concentration fields are computed from 9 a.m. of October 26, 2009 to 8
a.m. of the next day in a built-up district of Beijing and the results
show good agreement with observations. The advantage of proposed
approach is that the multi-scale effect of atmospheric motion is
considered and temporal evolution of flow structure in local urban area
can be simulated by large eddy simulation at moderate computation cost.
(C) 2012 Elsevier Ltd. All rights reserved.
