Date: Tue, 1 Nov 2005 11:39:55 -0800
Reply-To: Marc Sayer <marcsayer@COMCAST.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Marc Sayer <marcsayer@COMCAST.NET>
Subject: Re: Fuel ponderings
In-Reply-To: <43678B8A.3080300@charter.net>
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It isn't an issue of BTUs in a gallon of gas (or rocks or whatever),
it's an issue of getting the BTUs to do work. Right now our vehicles are
incredibly inefficient. Most of the energy in the fuel does no work, it
is simply waste energy (mostly heat). An efficient system would have no
radiator or cooling system, that waste heat would be used to do work.
And the exhaust gases would not be hot either, again that waste heat
would be used to do work. The exhaust would not make any noise because
that wasted energy, in the form of sound, would be used to do work. A
Turbocharger does reclaim some of the waste heat and sound energy in the
exhaust, but not a whole lot. In a highly efficient race engine we
currently use around 1/3 of the BTUs in a gallon of gas to do any actual
work. The other 2/3 are lost as waste energy of some form or another. In
the average street car we use around 1/4 of the BTUs. In other words you
are paying $2.50 a gallon but only getting about $0.62 worth of work.
Then we lose even more of that by conversion to waste heat in the drive
train, and to parasitic lost such as alternator, etc. It's like having
an employee who only works 15 min out of every hour, but who also takes
several minutes of the 15 minutes he "works" getting to and from his
work station.
With iron or steel components we are limited to around 50% efficiency in
the engine itself, but we should be able to build ceramic components
that will allow us to operate at higher efficiencies. We should and
could develop the technologies. We don't because there is not enough
financial incentive to do so. If we could extract 75% efficiency, we
could have cars running around 100-150 mpg.
We store kinetic energy in the car itself when it is moving, then we
convert that energy to waste heat when we use the brakes. Why not make
that energy do some work instead? And why rely solely on atomization to
facilitate combustion? Why not take Smokey's idea of a hot vapor engine
and and supply hot gasoline vapor rather than liquid gasoline to the
engine? We could use some of that waste heat to make that happen and
achieve 100% fuel combustion, a goal we are still no where near, even
with the best FI systems. That would reduce emissions, and increase
efficiency.
John Rodgers wrote:
> Given that the engines in use today in vehicles are heat engines, and
> the fuels that are used to provide that heat have specific values of
> BTU's per pound, how does one increase fuel efficiency, i.e., increase
> the miles per gallon on fuel?
>
> Reduce vehicle weight is one way.
> Reduce friction.
> Streamlining for the vehicle.
> Better fuel metering.
> Congress legislating that it be so??
>
> What else???
>
> Is it really possible to get more BTU's from a pound of fuel than a
> pound of fuel has?? What good does better mixture control and
> vaporization actually do? Given better mixture control and vaporization,
> can fuel efficiency actually be increased beyond where it is now, just
> on that basis?
>
> The whole business about fuels and fuel efficiencies is about energy
> exchange without energy loss. Is it possible??
>
> Given E = MC2, - the potential for large energy release from a tiny bit
> of matter - we have so much "potential" energy in the form of solid
> matter that it is mindboggling, yet even with Einstein's equation we
> cannot tap that energy in a truly controllable way The rock simply
> sits there or there is a big "Bang". Doesn't seem to be any "In between"
> point where we can meter off a bit of all that energy as we need it. I
> suppose one might consider an atomic pile as a controlled metering, but
> it is really a a controlling of natural radiation being emitted from a
> radio active substance. Not quite the same as deliberately "cracking"
> an atom of inert solid matter in a controlled way to siphon off a
> specific amount of it's energy.
>
> I really would like to be able to stick my banana peel and a beer - can
> and all - into the power generator on my Vanagon and fire up the "Flux
> Capacitor".
>
> There it is............this mornings pondering at coffee!
>
> Regards,
>
> John Rodgers
> 88 GL driver
>
>
--
Marc Sayer
Journalist, Photographer, Dog Trainer (APDT member #062956)
Board member - Western States Great Dane Rescue Association
Director of Operations & Training - Deaf Dane Rescue Inc.
Springfield, OR USA
My Homepage - http://gracieland.org
Deaf Dane Rescue Homepage - http://gracieland.org/DaneRescue/
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