Vanadis

3D dynamic with convection eulerian type model of air pollution transport in urban environment.

Convection-diffusion equation was solved using Finite Element Method.

FEM upwind scheme using unsymmetrical weighting functions has been developed for the unsteady convection transport equation.

Transport equation

Geometry: linear 8-node shape functions (Hexahedral elements)

Shape functions:

Weight functions:

Linear equations:

Steady state solution:

Dynamic solution:

Ground level View in front of chimneys from a distance 1000m

Results are presented on two normal surfaces.

At time=0 second 1st chimney is turned on.

After 1000 seconds 2nd chimney is turned on and wind direction has been changed.

The influence of the high building is visible.

Demo properties:

3D dynamic with convection model
time step = 100s
one pollution source at position: x=0m, y = 0m, h = 60m
space: 8000m x 8000m x 420m (hight)
plot (example on the left) - concentration at ground level after 2000 sec
output data are available for all time steps for every surface
changable parameters: Q_v[kg/s]; K_x,y,z[m²/s]; P[1/s]; v_h[m/s]; v_x[m/s]; v_y[m/s]; α[m/s];

author: Marek Chodorski

e-mail: marek_ac@wp.pl