"Falcon technology is extremely geometry tolerant and easy to use, enabling you to begin seeing and understanding air flow behavior within seconds of starting the application. Results update almost in real-time in response to changes in wind-direction and speed that you specify. Visualization tools available within the Falcon family of applications include 2D and 3D flow lines, shaded result planes, vector plots, and surface pressure shading. Quantified outputs include velocity, pressure, drag force, and drag coefficient."
Recently they also added a plug in for Revit which will allow you to analyze the affects of your building design to wind allowing you to position the building to either maximise the gain from a prevailing breeze or to shelter a specific area such as outdoor gathering spaces or a pool area.
It's very easy to use and set up using the correct time, location and desired orientation of the building.
you can also use Project Falcon on: