Isolating wing induced drag component
 

Hi,

From the total drag of a swept wing I'd like to determine the contribution of induced drag. So I thinking that the best way to do this would be to simulate the wing in a large fluid domain to get the total drag. Then simulate the wing but put a boundary at the wing tip and get another total drag value. As no wing tip vortex will be made in the second instance (okay there will be some vortical motion near the tip at the trailing edge) the difference between the two total drag values would be the induced drag. Also, there would be the slight difference due to the profile drag on the wing tip itself.

So my questions are:

1. What would be the best wing tip boundary condition? A free slip wall?
2. Is there a better approach that could be used instead?

Thanks.

The concept that total drag=profile drag+induced drag is a simplification anyway so any simulation aimed at separating the components will have to be a bit of a compromise. So having said that, a free slip wall sounds as good as anything.

I've found some journal papers on the wake integration method. Which can be used to decompose drag in wave, viscous, induced etc parts. However, these papers only give calculus equations and contours plots and not how to actually obtain the data.

Does anyone have any experiance in this to help?

Thanks