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Cd · 01-11-2021, 03:16 PM

I'm adding some NACA ducts to my cars' box cavity.
I'm running into some placement issues with the ducts, since they need to line up with the airflow around curved surfaces.
Luckily for me, I had previously done a tuft test, and I am able to overlay the image onto a photo and guess at the correct placement.
When lined up into the direction of the airflow, the ducts look odd. Nothing matches the angles of the other ducts, and they look crooked.
I have done two ducts on top, but will wait to cut out the others till I get advice.
Please have a look at the images and let me know what angles you think the ducts should be at.
Thanks !

01-11-2021, 03:16 PM	#1 (permalink)
Cd Ultimate Fail Join Date: Feb 2008 Location: Austin,Texas Posts: 3,585 Thanks: 2,872 Thanked 1,121 Times in 679 Posts	Need advice on NACA duct placement to airflow on curved surface. I'm adding some NACA ducts to my cars' box cavity. I'm running into some placement issues with the ducts, since they need to line up with the airflow around curved surfaces. Luckily for me, I had previously done a tuft test, and I am able to overlay the image onto a photo and guess at the correct placement. When lined up into the direction of the airflow, the ducts look odd. Nothing matches the angles of the other ducts, and they look crooked. I have done two ducts on top, but will wait to cut out the others till I get advice. Please have a look at the images and let me know what angles you think the ducts should be at. Thanks ! Attached Thumbnails