Hello all, I am trying to monitor the drag force on an airfoil held stationary in an imposed flow, I had suspected my Cd value to be somewhere around 0.2 for this design, but in my simulation I am getting values in the range of 15.00-20.00. Are the force monitors supposed to give the actual value of the drag and lift co-efficient, or is there some relation I am supposed to apply to scale approrpiately?

Any recommendations?

Thank you

Skander

I should also say that I often get negative Cd values? This doesn't make any sense to me, but am wondering if it is due to the fact that I am imposing the flow on the airfoil rather that assigning a moving wall boundary to the airfoil and letting it move through stationary fluid.

Hi Skander, Did you setted up the references values correctly? If not, go to Report->References Values and put all the info that it needs. Try to match unity values with the model, for example, in an airfoil try to have the airfoil with 1 meter of lenght, and put that value in the references values. Then, can you tell me if you get an exact value of Cd? I´m dealing with it right now and I would like to know different strategies for that problem. Hope this helps!