Negative Drag Coefficient Results (but not always)

Project Support
1

Hi there,
I am wanting to run some comparisons between 5 simulations. However, I am getting negative figures for the drag Co.

Firstly, am I doing it correctly? have I entered all of the right details? I realise that this is not your job to check these things - but maybe you can point me in the direction where I can get assistance. Particularly in the Forces and Moments catagory.

I have some other simulations that return positive lift and drag co. = +L/D result. - https://www.simscale.com/workbench/?pid=7899718963401376497&mi=spec%3A1a655ef8-710e-437f-87f8-e817d7b52824%2Cservice%3ASIMULATION%2Cstrategy%3A63

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2

Hi!

In the future, please keep it to one post to have a better overview of what you are working on without jumping back and forth all the time :wink: Make sure you apply a no-slip BC on your airfoil and also that the values of your result control item are applied in the right direction with the correct direction.

I have already commented on your other post and tagged the PowerUsers.

Best,

Jousef