John
It is great fun to try to figure this stuff out.
Drag goes up with the square of the speed and HP goes up with the cube of
the speed but both are directly proportional to air density. (see Katz "Race
Car Aerodynamics" p 47).
I always thought we should go faster in the cool because rolling friction is
independent of air density but the other factors such as traction seem to
reduce the affect.
Dave the Hayseed
----- Original Message -----
From: "landspeedracer" <landspeedracer@msn.com>
To: "Marge and/or Dave Thomssen" <mdthom@radiks.net>; "Land-speed Racers"
<land-speed@autox.team.net>
Sent: Sunday, September 15, 2002 9:49 AM
Subject: Re: Cool Air and drag
> Dave
>
> Just as the HP required to go faster goes up exponentially, I wouldn't be
> surprised that the HP required to go faster through the denser air goes up
> in a similar fashion. I know at 220+ MPH my car (normally aspirated)
wasn't
> breaking even.
>
> John
> ----- Original Message -----
> From: "Marge and/or Dave Thomssen" <mdthom@radiks.net>
> To: "Land-speed Racers" <land-speed@autox.team.net>
> Sent: Sunday, September 15, 2002 10:38 AM
> Subject: Fw: Cool Air and drag
>
>
> > Right tree.
> > Drag is proportional to air density and so is normally aspirated HP-you
> > break even.
> > NO2 , nitro, and supercharging have the benefit of being able to
increase
> > engine air density with adjustments during the heat of the day when air
> > density and drag are lower.
> > Dave the Hayseed
least> >
> > or
> > > N2o would benefit from running in the hottest part of the day
> drag
> > > caused by the rho factor of the equation or am I barking up the wrong
> > tree
> > > Gary
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