Date: Mon, 22 Mar 2004 18:08:15 -0800
Reply-To: Randy Bergum <organslave@EARTHLINK.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Randy Bergum <organslave@EARTHLINK.NET>
Subject: Re: Vangaon Drag Coefficient?
Content-type: text/plain; charset=US-ASCII
The Reynolds numbers we are talking about vary hugely for the sphere
measurements - I don't recall much of anything these days, but the speeds
vary by many orders of magnitude. For the van driving in reasonable speed
ranges, say 10-80 MPH, the Cd is probably fairly constant, not unlike tire
drag.
Randy
> [Original Message]
> From: P.Dooley <pdooley@gte.net>
> To: Randy Bergum <organslave@EARTHLINK.NET>; <vanagon@GERRY.VANAGON.COM>
> Date: 3/22/2004 5:47:44 PM
> Subject: RE: Vangaon Drag Coefficient?
>
> OK, so the Vanagon has a fixed shape and a sphere has a fixed shape.
> Seems like what you are saying is the Cd is variable for a sphere but
> fixed for the Vanagon?
>
> How is that possible? I think either shape profile is variable
> depending on the Reynolds number. I would bet the Vanagon profile would
> go above 1 in the right conditions.
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf
> Of Randy Bergum
> Sent: Monday, March 22, 2004 8:04 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Re: Vangaon Drag Coefficient?
>
> Yes...... a sphere can vary from the low 0.2 or so to around 2.0-ish
> depending on Reynolds number (the ratio of inertial to viscous forces).
> How weird is that!
>
> The Van CD of 0.44 is what I remember also.
>
> Randy Bergum
> 1990 Carat
>
>
>
> > [Original Message]
> > From: Bruce Nadig <motorbruce@HOTMAIL.COM>
> > To: <vanagon@GERRY.VANAGON.COM>
> > Date: 3/22/2004 12:36:48 PM
> > Subject: Re: Vangaon Drag Coefficient?
> >
> > Do drag coefficients ever go above 1.0?
> >
> > Cheers,
> > Bruce
> >
> > >From: "J. Harvey" <jtharvey2@HOTMAIL.COM>
> > >Reply-To: "J. Harvey" <jtharvey2@HOTMAIL.COM>
> > >To: vanagon@GERRY.VANAGON.COM
> > >Subject: Vangaon Drag Coefficient?
> > >Date: Mon, 22 Mar 2004 11:07:03 -0800
> > >
> > >Anybody know it? -john
> > >
> > >_________________________________________________________________
> > >Check out MSN PC Safety & Security to help ensure your PC is
> protected
> and
> > >safe. http://specials.msn.com/msn/security.asp
> >
> > _________________________________________________________________
> > Get reliable access on MSN 9 Dial-up. 3 months for the price of 1!
> > (Limited-time offer)
> http://click.atdmt.com/AVE/go/onm00200361ave/direct/01/
>
|