[Marcelo]

I need to calculate the drag coeficient for an object subject to diferent velocities. In order to make that I think in two posibilities: to simulate a wind tunnel (a cylinder with slip-wall, inlet and outlet boundary conditions) or use a Far Field boundary condition. I have to make a lot of cases, so I'm making a stady analysis. I did a wind tunel with a 5L radio and a longitud of 20L, and in order to use the Far Field condition I used a domain of app 10L of radio. With the two posibilities I obtain diferent results. What is the more correct way to do this?

Regards