AirWare:     urban air quality
assessment and management

TIMES: dynamic 3-D modeling

TIMES is a dynamic, 3-D (multi-layer) Eulerian model developed by ESS in collaboration with the Institute for Mathematical Modeling of the Russian Academy of Sciences, Moscow:

where:

Q is the emission strength,
c the pollutant concentration
w the wind speed
Dh and Dv the horizontal and vertical diffusion, and
R represents chemical transformation processes.

The model uses a multi-stage diagnostic wind model to generate sequences of the 3-D wind fields, and processes time variable emission stregth as well as stability class and mixing height parameters.

The model can be used both at the meso-scale for regional and urban-scale analysis, as well as on a micro-scale for street canyon simulations of within a chemical plant for accidental releases.

For the near-field street canyon and process plant modeling, the model considers, in addition to the DEM and surface roughness, also the geometry of obstacles such as buildings. Time variable emission strength and time variable meteorological conditions can be represented.

Dynamic 24 hour example