Point taken.
I gather also that a "matt" surface has been shown to be beneficial on
gliders, although it is attributed to being because the slightly roughened
surface causes rainwater to spread as a film, rather then bead-up (the
beads then causing early flow separation).
I notice that Toyota use big dimples on the rearward side radiator inlets
on the latest MR2; but possibly more for style than effect.
Duncan McF.
On Sunday, August 18, 2002 4:58 PM, JW [SMTP:xs191@attbi.com] wrote:
> Duncan.
>
> Sorry for the shot, but your new response was worthy. A couple more
sentences explains your position, which is much more useful than
> just stating it.
> It is an intriguing subject. When I initially brought this subject
up, I had recently been fondling the wing of some sort of military
> craft. I don't recall what it was. I described the surface as feeling
like 'smooth sandpaper'. The military officer explained that
> there were two reasons for the rough surface. One was to contribute to
the stealthyness, and the other was speed. He didn't go into any
> detail as such, but said that the speed increase was dramatic over the
same airplane with a smooth surface.
>
> Jeff
>
> McFadyean wrote:
>
> > Thanks for the insult!
> > If you read the Sport Aviation article carefully (i.e. between the
lines) I think the conclusion is apparent.
> > Dimples work well on golf balls. On a well proportioned airfoil at zero
angle of attack the effect is also zero or negative.
> > By comparison, VGs on wings can improve certain aerodynamic
characteristics; but I never heard that terminal speed was one of them.
> > I'm sure that dimples have their place, but in situations of making the
best of an already bad aerodynamic job
> >
> > Duncan McF.
> >
>
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