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Old 05-19-2010, 06:26 PM   #12 (permalink)
aerohead
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Quote:
Originally Posted by tasdrouille View Post
To me, if the dimples were to work on such an helmet (can't say they do or don't without WT testing), Louis Garneau placed them probably in the worst possible place. You'd want the dimples where the flow is transitioning.
I'm going to agree on the positioning.
For turbulent boundary layer,which I believe is the premise of the dimples,only a small area,right at the forward stagnation point would be the proper location.
In the 'FLOW-IMAGES' photos there is an image of a submerged bowling ball in the US NAVY hydro lab in Pasadena,California.You will see that only a very small area has sand adhered to the leading 'edge',adequate to force the transition to higher Reynolds number.
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