Wind speed increases after buildings…

Hi Eddy3D team and All,

We have been simulating two cases with a model consisting of context volumes and trees/screens assigned as Darcy-Forchheimer Model values. We can simulate the cases as shown below. However, we are getting some strange results, as shown in the picture where the wind speed is decreasing in front of the buildings and increasing behind the buildings. The initial wind speed is also different although the inputs are the same.

Left: Model with solid geometry and trees/screens assigned with Darcy-Forchheimer Model
Right: Model including only the solid geometry

Are there any good reasons for these differences and unexpected results?

Any recommendations on how to get more realistic results are appreciated. Thanks,

cheers,
Bjorn