Airfoil Analysis (drag coefficiet)
 

Hi, currently I am using CFD to analysis on an airfoil. And my question is about finding the spot for drag coefficient.

Here is what I did, I selected the forces under the report drop down menu. In there, I obtained drag coefficient by using the vector component. Once I have specified it, the forces as well as some other coefficients will be listed on the window. so here is my question; could someone please tell me which column and row that indicates the drag coefficient.

Thank you so much.

Re: Airfoil Analysis (drag coefficiet)
 

Total force or total coefficient. But for coefficient you must specify your reference values (velocity, area etc.), which will be used for calculation of drag coefficient (report->reference.values).

Re: Airfoil Analysis (drag coefficiet)
 

ha ok, thats mean more clear thank you al_c.

As for specifying the reference values, could you tell me which are these reference values more appropriate in my analysis? In my case the instructor asked us to select the pressure far field as reference values, but I did not get it why can't we select others reference values and what they are for.

As for the total force, I suppose that is my drag force in my case right?

I would appreciate if someone could answer this for me. Thank you

Re: Airfoil Analysis (drag coefficiet)
 

Usually density and velocity of ambient flow, wing area and ambient pressure are reference values for force coefficients of airfoil (in 2D case chord length instead of wing area).

As for the total force, I suppose that is my drag force in my case right?

Yes, if you set right direction. Drag force operates in direction of ambient velocity vector.