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.

Model parameter input data can depend on position and time step.

Transport equation

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

Shape functions:

Weight functions:

Linear equations:

Steady state solution:

Dynamic solution:

Linux / Windows + Fortran compiler

Optional: Nvidia CUDA Toolkit

Example for 2.8 million nodes, 100 sec. time step:

4 Gbytes RAM

Intel Core i5-4590 @ 3.30GHz - it takes 45 sec. to resolve linear equations for one time step

GTX 1060 3Gbytes - 17 sec. to resolve linear equations for one time step

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