Date:         Fri, 23 Aug 2002 21:18:49 +0100
Reply-To:     Clive Smith <clive.harman-smith@NTLWORLD.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Clive Smith <clive.harman-smith@NTLWORLD.COM>
Subject:      Re: Custom Scoop Update - Should you care! FISH Y
Content-Type: text/plain; charset="iso-8859-1"

Very good, hope you had your fibreblend before all that pooping.
Anyway, anyone aware of the sometimes disconcerting dichotomies between
theoretical and empirical aerodynamics would of course back it up with a
pressure plot along the side of the van with a few static tappings spaced
judiciously down through the duct.

We await your Excel spreadsheet data and accompanying graph with eager
anticipation. No doubt it will be supported with pictures of a tufted van
side and a few calculations of mass flow rate Vs vehicle velocity.

Till then, again, great stuff - the full poop indeed!

Clive
'88 Syncro Transporter (sans static tappings all along its side)

----- Original Message -----
From: "Chris S." <MrVolkswagen@HOTMAIL.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Friday, August 23, 2002 3:49 AM
Subject: Re: Custom Scoop Update - Should you care! FISH Y


> Alright all you pooper-scoopers!  ;-)
>
> Our Vanagon scoops work.  Why?  The only requirement of an body opening to
> draw in air is to have lesser air pressure within that opening and greater
> air pressure just outside of that opening.  Them fancy words are "pressure
> differential" -- weather folk call it wind, but this one does not require
> any prior consumption of beans.  If you look carefully at our scoops, they
> are designed quite ingeniously.  First, the leading edge of the scoop lies
> in a depression.  This causes an initial drop in air pressure causing the
> air to turn in towards the body.  The rear edge of our scoop is placed
just
> wider than the surface of the windows -- look how the edge just below the
> windows leads to the rear of the van and then turns up and behind the
scoop.
> This causes the air flowing next to and over the windows to ram directly
> into the scoop.  Also it creates an area of higher pressure.  This
> high-pressure air is sucked into the lower pressure area at the leading
edge
> of the scoop making the entire unit functional.  The slats in the scoop
are
> there to direct the air into the bottom of the air ducts lessening the
> turbulence.  Next time you're outside stand in front of the Vanagon and
look
> down the side towards the scoops.  You'll see what all the poop is all
> about.
>
> The scoops served the air-cooled motors well, where they provided cool and
> relatively dust-free air, hence their high placement on the body, for the
> sealed engine compartment.  There the engine fan forced the air over the
> cylinders and out the bottom.  For the H2O motors those same scoops
provide
> cool intake air and help to keep engine bay temperatures lower.
>
> You want to make these even more functional?  Provide a way to increase
air
> pressure just outside of the scoop.  This could be accomplished by
something
> as simple as a piece of aluminium protruding perpendicular to the body
just
> behind the scoop.  Not much would be needed - maybe an addition 2cm or so.
> Heck, you could experiment and use a piece of thin wood that could be
jammed
> between the scoop and the body.
>
> Well, all this scoop talk and I'm missing my bed time.  Maybe I'll poop
and
> go to bed.
>
> Chris.
> '85 Westy.