City-scale wind simulation with topography?

Q: Are there precedents for urban-scale outdoor windflow models, with topography?

Hi everyone- I am coming from the AEC/3d modeling/Rhino-Grasshopper world. Following a great series of tutorials, I am at a point where I can get a OpenFOAM Case File and ‘slice’ it and visualize it to show results. I have been inputting buildings of an urban block, usually simplified to a single plane, and then seeing the results @ a person’s height for ‘human comfort’ simulations.

I have now been requested to do this but with topography. I have managed to get a mesh with some results, but I am not sure how to visualize these results for people who don’t recognize the terminology “CFD.” (which still includes me, really)

The input STL looks like below - a pretty large area with foothills

If I slice through the results at a Z normal, the results look as such (U magnitude Time 6)

I think ideally we would still talk about pedestrian comfort (roughyl 1.5 m from base plane)… is there a way to offset the topography STL and use that to create a sliced result?

Or is there a better way to visualize this that I haven’t considered? Thank you!

Hi, see plugin GitHub - mobigroup/ParaView-plugins: ParaView plugins which allows to load DEM as GeoTIFF or NetCDF file and even place image (Google Satellite map for example) on it.

I have used the following in the past:

  • load in the volumetric results
  • Load in the bottom surface / topography as stl
  • transform the surface with 1.5m upwards
  • Resample with dataset, source foam, destination transform
    results in: