Re: Rougtero Water Screw

["Kris Ames" <kris@cioe.com>]

----------
> From: Jevan Furmanski <furmansj@expert.cc.purdue.edu>
> To: Steve Ames <steve@ns1.cioe.com>
> Cc: gmlist@cioe.com; jedi@ecn.purdue.edu; khelek@ns1.cioe.com
> Subject: Re: Rougtero Water Screw
> Date: Thursday, October 29, 1998 2:15 PM
> 
> 
> 
> On Thu, 29 Oct 1998, Steve Ames wrote:
> 
> > > This water screw crap is what had DiVinci convinced that he could
fly.
> > > Well, he couldn't and this technology isnt as far reaching as
people are
> > > making it.  Especially since all the water on Jearn is clean and
fresh.
> > > There isn't a need for water screws really.  Maybe a shallow well
or two.
> > 
> > To fly you have to move a lot of air (very compressible stuff) at a
> > pretty good clip. To pump water (to either move the water or, in the
> > case of screw powered boats and subs, move the pump) is much easier
> > since water is not compressible. Dervish powered screws are where its
> > at :)
> > 
> > Using the screw pump you can change the tubing diameters to get
> > pressure variences to force better speed than just moving water.
> > 
> > Using an inverted screw could be even more successful...
> > 
> > 						-Steve
> 
> 
> unfortunately, the flow rate can't change, so the point is moot.  A
tower 
> from which the water can flow is the best plan.  Screwing air will
never
> work, but that is a fluid dynamics thing and you should ask Kris.
> (hahaha)  We had to wait for lift from aero to fly.> 


True flowrate (volume per time) will not change but the velocity at any
point can be changes by bigger/smaller:

m'(mass flow rate) = Density * Velocity * Crossectional Area of pipe. 
Assuming the mass flow rate is constant (it could vary if the people
powering the screw are intermittent and lazy)  the velocity must change
when the pipe diameter changes since density is also a constant.

As far as screwing air (unless we are not talking spider monkey's here), 
I don't think that is possible either mainly because air is compressible
and there fore would not enter the screw to begin with unless it was
pressurized to do so.  If you are capable of pressurizing the air then
their in no need to use a screw any way since you can make things flow
due to the pressure differential.

-Kris

> 
> Dervish is a shord duration spell.  I think that mutated cows for
strength
> or something obnoxious would be much more effective.  especially since
> they can move heavy structures, and keep them moving with momentum on
> their side.
> 
> Jevan
>