The Quasi-Solid Box Method for Simulating Wind Around Obstacles in the
System for Atmospheric Modeling
Abstract
A novel method to simulate the wind and turbulence around obstacles,
such as buildings, has been developed for use in a computer model that
was previously used only to study turbulence and clouds over flat Earth
surface. The method, called the Quasi-Solid Box Method, forces the
simulated flow to stop in the model grid-cells that are inside an
obstacle. The accuracy of the method is tested using cases of a flow
past an idealized single rectangular building, a cubic building rotated
by 45o, and a building in the form of a cylinder. The
simulations are compared with wind tunnel observations around a small
model building and to results from other models. The modeled gas tracer
dispersion around the building also agrees quite well observations. We
also report results for successful simulation of a flow around a cubic
building rotated by 45o relative to the flow, and
around a building in the form of a cylinder of aspect ratio of one. The
main appeal of the new method is its simplicity that requires very minor
modifications to the model code. The improved model can be used for
detailed studies of the impact of climate change on urban environments.