land-speed
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Re: Ballast

To: "DrMayf" <drmayf@teknett.com>, "Dave Dahlgren" <ddahlgren@snet.net>
Subject: Re: Ballast
From: "glen barrett" <speedtimer@charter.net>
Date: Wed, 4 Jul 2001 13:32:07 -0700
MAyf
The exhaust was pointed up and slightly back. It is a shaft turbine
connected to the drive train. Don told me and others the thrust to weight
ratio would not be enough to start moving the car.
Glen
----- Original Message -----
From: "DrMayf" <drmayf@teknett.com>
To: "Dave Dahlgren" <ddahlgren@snet.net>; "glen barrett"
<speedtimer@charter.net>
Cc: "Joe Amo" <jkamo@rapidnet.com>; "Smith, Simon-Pierre"
<Simon-Pierre.Smith@PSS.Boeing.com>; "land speed"
<land-speed@autox.team.net>
Sent: Wednesday, July 04, 2001 10:53 AM
Subject: Re: Ballast


> Silly sounding or not, It was a good protest! Why, well it is a jet engine
> he is using ang the realpurpose of the jet is to move large quantities of
> hot air backwards. I am not sure where the test was conducted, but if it
was
> on a smooth surface, not the mud dry lakes, then given some time it would
> have accelerated. Look at thrust; it had lots of power but it took forever
> to reach even a hundred miles an hours. It just takes time to over come
> inertia with hot air, sorta like this group sometimes. As to the 10% of
the
> power of a piston engine beig made by hot exhaust gas, I am really
> skeptical. Thrust from hot air is same as rocket engine where the formula
is
>
> T  =  mdot * Ve
>
> which is mass flow per second * exit velocity in ft per second.
>
> All that at the exit plane of the tail pipe. convert your cfm engine flow
to
> pounds mass per second and multiply it times what you think is a good
> velocity...won't be 10% of hp I don't think. MAybe, but.....
>
> mayf the red necked ignorant desert rat inPahrump
>
> ----- Original Message -----
> From: "Dave Dahlgren" <ddahlgren@snet.net>
> To: "glen barrett" <speedtimer@charter.net>
> Cc: "Joe Amo" <jkamo@rapidnet.com>; "Smith, Simon-Pierre"
> <Simon-Pierre.Smith@PSS.Boeing.com>; "land speed"
> <land-speed@autox.team.net>
> Sent: Wednesday, July 04, 2001 8:03 AM
> Subject: Re: Ballast
>
>
> > That was a silly protest and should have been demised from the
beginning.
> Every
> > engine has a thrust factor in the exhaust period no exceptions... It has
> been
> > well documented and accounted for for decades, most notably in
airplanes.
> Piston
> > engines account for about 10% of the rated HP in thrust. Where you aim
it
> is
> > sort of up to the builder!
> > Dave Dahlgren
> >
> > glen barrett wrote:
> > >
> > > List
> > > A couple of years ago the issue of Vescos car came up and a protest
was
> > > started by Jim Fueling stating the Vesco car was assisted by thrust
from
> the
> > > exhaust. I and several others were in attendance at this meeting.
Vesco
> > > proved that the exhaust flow / pressure was not enough to move the
> vehicle
> > > at full thrust alone. With any drive to the wheels the vehicle will
not
> > > move. I don't remember the exact numbers but they were very low. Some
> where
> > > in my file I believe I have the engineering reports submitted by Don
> Vesco.
> > >
> > > It's like Fueling's Chevy powered streamliner (4 wheels )with one
> removed
> > > being called a motorcycle. My feelings on that issue is a motorcycle
has
> two
> > > wheels unless it is a real side hack racer which there is a class for.
> > > Lets see what this starts.
> > > Glen
> > > ----- Original Message -----
> > > From: "Joe Amo" <jkamo@rapidnet.com>
> > > To: "Dave Dahlgren" <ddahlgren@snet.net>
> > > Cc: "Smith, Simon-Pierre" <Simon-Pierre.Smith@PSS.Boeing.com>; "land
> speed"
> > > <land-speed@autox.team.net>
> > > Sent: Tuesday, July 03, 2001 7:51 PM
> > > Subject: Re: Ballast
> > >
> > > > I am with your line of thinking Dave, BUT
> > > > with the aero/go fast expertise that the
> > > > Vesco's have, it would also seem logical
> > > > that they have good reason for their design...
> > > > Joe :)
> > > >
> > > > Dave Dahlgren wrote:
> > > >
> > > > > Thinking logically it would seem the down force to be canceled by
> the
> > > increase
> > > > > in aero drag. It has to make a lot bigger hole in the air if it
> comes
> > > out 90
> > > > > degrees to the direction of travel. If you aim it out the back it
> will
> > > do no
> > > > > harm and might fill in the hole to a certain degree that you are
> making
> > > in the
> > > > > air. 'Base drag' and all that stuff.
> > > > >
> > > > > Joe Amo wrote:
> > > > > >
> > > > > > yes, but when it is applied through the wheels
> > > > > > you get to take advantange of all that multiplied
> > > > > > torque from the motor, and that likely pushes
> > > > > > alot harder than any thrust derived from pushing the exhaust
> > > > > > against the air, perhaps that is why Vesco uses it for
> > > > > > downforce......
> > > > > > Joe :)
> > > > > >
> > > > > > "Smith, Simon-Pierre" wrote:
> > > > > >
> > > > > > > Seems to me that for every pound of downforce you get from
your
> > > exhaust, you get that much times your coefficient of friction out of
> your
> > > tires.  On salt you'd be better off pointing the exhaust back so you
get
> > > pure thrust.  Remember that the thrust doesn't go through the wheels
so
> it
> > > is not traction dependent.  At Maxton I'd figure you can get a
friction
> > > coeff above 1 so it might be worthwhile pointing it up.
> > > > > > > One other point, if the exhaust is pointed up and is aft of
the
> rear
> > > axle it will lighten the front wheels.  This will give it a greater
> > > effective downforce on a rear wheel drive car.  Hard to make up for a
> > > coefficient of friction of about .5 though.
> > > > > > >
> > > > > > > Simon-Pierre Smith
> > > > > > >
> > > > > > > > ----------
> > > > > > > > From:         Joe Amo[SMTP:jkamo@rapidnet.com]
> > > > > > > > Reply To:     Joe Amo
> > > > > > > > Sent:         Sunday, July 01, 2001 11:08 PM
> > > > > > > > To:   Dan Warner; land speed
> > > > > > > > Subject:      Re: Ballast
> > > > > > > >
> > > > > > > > Here you go Dave, an exhaust
> > > > > > > > collector that is directed up for
> > > > > > > > the acceleration heavy portion of the
> > > > > > > > run, that rotates to or towards a more
> > > > > > > > rearward aspect to enhance drag toward
> > > > > > > > the end of the run.....
> > > > > > > > Joe
> > > > > > > >
> > > > > > > > Joe Amo wrote:

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