Quote:
Originally Posted by aerohead
In the FLOW-IMAGES galleries,there are some color shots of the VW Rabbit which Hucho,Jansen,and Emmelman were involved with.There is also an overhead ( plan view ) of the Rabbit nose in smoke.
You can see what little radius is required to prevent separation.
One of the SAE papers reported 80-mm in full-scale for leading edges.I think that translates to 4 and a fraction in inches.
But there is a formula,something like 0.03 X width = R.
I didn't expect to be here today but we finished early in Dallas and I got in before traffic formed.I'll try and remember for next time.
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Boy! I wasn't even close! My memory is FUBAR.
Hucho has two reports:
the first occurs on page 181.A table is presented and the formula presented is Radius divided by the square-root of the area of the face you're streamlining.The minimum drag occurs for values around 0.4.
The second reference is on page 423,Figs 11.25 and 11.26.The drag relationship is for radius divided by width ( which also happens to be the height) and minimum occurs in the neighborhood of 0.06- 0.10.