Moving floor/ground approximation?
 

I'm working with CFDesign doing some basic analysis of wings and diffusers on racecars, and having trouble getting my head around how I would simulate the ground moving beneath the car such as in a rolling road windtunnel? Basically the air needs to move twice as fast past the ground compared to the model.. any ideas?

Thanks,

Ground moves with same velocity as the air. You need to impose a tangential velocity to the ground in your simulation.

Much appreciated, I'm not familiar with that in CFDesign but I'll give it a shot.