land-speed
[Top] [All Lists]

Re: Tires

To: Skip Higginbotham <saltrat@pro-blend.com>
Subject: Re: Tires
From: Rick Hammond <r.hammond@sympatico.ca>
Date: Sun, 03 Mar 2002 15:37:00 -0500
Skip Higginbotham wrote:

> Hello Ed,
> Tire frontal area is a really big issue at any speed as drag increases
> greatly with increase in speed and the Cd is relatively high.......but how
> about considering this......the top of the tire is moving twice as fast as
> the car, relative to the wind, and the bottom of the tire is not moving at
> all relative to the wind (no slippage). So if you cover the top of the
> tire, most of the skin drag would be eliminated? Here's one to calculate,
> Mayf. The desired answer might be "How much of the tire to cover?" or what
> is the real drag of an open tire?
> The top of our tires were going 542 MPH at the "5". The top of Law's tires
> were going 700 MPH. Hammond's at 600. I wonder what sonic shock waves will
> do to tire tread...or.....how narrow a tire can we use and still be safe
> from excessive distortion? Seems we had a thread about flexing some months
> ago......wonder what happened? I seem to remember some sensitivity about
> it.....
> Skip (One would think that I have enough to do.....)
>

Skip,
So...if you had a horn pointed backwards as you approached the speed of sound 
and
you honked...??
Now I won't be able to sleep ;-)
If the boundary layer comes into play, maybe we should have rotating nose
cones...ok, better stop.
Cheers,
Rick

///  unsubscribe/change address requests to majordomo@autox.team.net  or try
///  http://www.team.net/mailman/listinfo
///  Archives at http://www.team.net/archive/land-speed


<Prev in Thread] Current Thread [Next in Thread>