Hey, Mr. Skip...
yes you certainly may see the house. Hell, we might even be moved in, but I
am not holding my breath! Carpet is supposed to be this Friday, but I bet it
doesn't happen till next week. Then there is the remainder of the cabinets,
a built in set of cabinets the flank the fireplace. And, and, and... But if
you get here we can see it! When you going to be here?
Oh, one of the things I failed to mention regarding the relative wind
blowing on that open tire (lakester) is that the wheel produces the Magnus
effect (flow over a rotating cylinder), if I remember correctly. And that is
LIFT. so you really do want to kill the flow across those big fat tires at
speed. Add some lift to an expanded tire with smaller contact patch and
zooooomiiiieeee, yehaaaaa!
mayf
----- Original Message -----
From: "Skip Higginbotham" <saltrat@pro-blend.com>
To: "DrMayf" <drmayf@teknett.com>; <land-speed@autox.team.net>
Sent: Monday, March 04, 2002 4:38 PM
Subject: Re: Tires
> Mayf,
> Congratulations on your home and shop!!! Having done that a couple of
> times, I know how much fun it is. (-:(-: Would love to see it later on
this
> month when we are there.
>
> Thank you for taking your time to take a stab at this problem. From your
> analysis and conjectural deduction, it would seem that covering/enclosing
> the upper half is the most important as it reduces the drag by about ?%
> (may be about 65% or so) because the free stream air now only interferes
> with the enclosure and not the rotating tire. The rotating tire and the
> shear between it and the enclosure have a drag loss but the fenderwell
> (enclosure) vents can reduce this some. We will add the vents like the
> sports cars do. How far down the tire should the enclosure go depends on,
I
> suppose, the diameter of the tire.....or does it? As the tire surface
> airspeed approaches 0 (when the tire is contacting the surface, no
> slippage) drag also approaches 0. So the lower part (?%) can run in free
> stream air with little drag penalty.
> We are building enclosures for the rear tires on the "Rose" and results of
> this discussion will directly effect the amount of tire that gets
enclosed.
> Right now I would cover 75% of the tire and leave the bottom 7-8" out in
> the open. Simplifies the fairing problem a lot! I'll see if my little mind
> can figure out the differential airspeed for the lower 8".
>
> How any of this would work in a fenderwell that is out of free stream air
> absolutely baffles me. But it might help some if the airflow in the
> fenderwell is significant and the direction can be established. Prolly
need
> some tunnel time for this one.
>
> I have seen Cd for open tires that vary from .19 to .7.......anybody have
> some measured data?
>
> Skip (This is what makes this sport fun!)
>
>
>
>
> At 02:53 PM 3/4/02 -0800, you wrote:
> >Skip, you asked some really great questions in this post! I am not sure I
> >can answer them in other than general terms and thoughts. See the
thoughts
> >interspersed with what you wrote below...
> > Subject: RE: Tires
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