Here are a few observations..
- The lift and drag forces are many times higher when the wind is incident on the sides of the vehicle. Not surprising seeing how cars are designed to go forward, not sideways. However, it does provoke some thoughts as to how you might design a vehicle that minimizes forces over the entire range of possible wind directions.
- There is no orientation that produces any sort of down force. In fact, the lift is always at least equal to, and in many cases significantly greater than the drag. It's possible that this model is missing any effects due to flow moving under the chassis in the real world.
- The rotation rate that I used is probably influencing the results since the symmetric model should produce identical force profiles if each incidence was run as a steady state solution. It was just the easiest way to get the flow solver to give me a nice set of data for the animation. :)