Re: TheAirCar

From: The Phantom (phantom_at_aol.com)
Date: 10/21/04 

Date: 21 Oct 2004 16:56:13 -0500

On Wed, 20 Oct 2004 17:44:24 -0700, Don Lancaster <don@tinaja.com>
wrote:

>Eunometic wrote:
>>
>> Don Lancaster <don@tinaja.com> wrote in message news:<4175E00D.D88BFE38@tinaja.com>...
>> > Eunometic wrote:
>> > >
>> > > Roland PJ <roland@rolandpj.com> wrote in message news:<cl43b9$7d3$1@ctb-nnrp2.saix.net>...
>> > > > Fred McGalliard wrote:
>> > > > > "Ivar S. Ertesvåg" <ivar.s.ertesvag@ntnu.no> wrote in message
>> > > > > ...
>> > > > >
>> > > > >>This is not a 6-ton american SUV but a relatively light car for urban
>> > > > >>transport.
>> > > > >
>> > > > >
>> > > > > Might be very interesting if the compressed gas is used in liew of a battery
>> > > > > for a car that runs mostly on electric power from an overhead wire or
>> > > > > similar.
>> > > > >
>> > > > >
>> > > > I think the application is for taxis that have a limited (geographical)
>> > > > range. But why not go for electricity?
>> > > >
>> > > > The only advantage of compressed air motor over electric motor is peak
>> > > > power. I think super-caps can solve that, so why bother with compressed air?
>> > > >
>> > > > Roland
>> > >
>> > > A compressed air motor and storage system doesn't require any exotic
>> > > or limited supply materials such as nickel, neodynium, boron,
>> > > sumarium, cobalt, platinum, lead etc that set a limit to cost
>> > > reductions. These problems may be solved with switched reluctance
>> > > motors and carbon nanotube based hypercapacitors but most certainly
>> > > haven't yet.
>> >
>> > The fact remains that a compressed air storage system cannot store
>> > jack*** in the way of energy density.
>> >
>> > And that both the compression and recovery processes are exceptionally
>> > ineffficient.
>> >
>> > See http://www.tinaja.com/glib/energfun.pdf
>>
>> You don't know what you are talking about.
>>
>> Guy Negre who has put his own time and money on line is an EXPERIENCED
>> and famous Formula 1 racing engine designer. Formula 1 engines are
>> the peak of development in heat engines and I'd put his credibility
>> and knowledge of the laws of thermodynamics ahead of you any day.
>>
>> Sorry, you'll eventually have to remove those silly web pages
>> eventually. Best do it now before it become too much of a glaring
>> embarasement.
>>
>> MDI are managing a piecewise near isothermal (constant temperature)
>> expansion of the air: through the use of heat exchangers and a special
>> piston motion they are managing to add heat from the evironment into
>> the sucesively expanding air at a rate fast enough to stop it chilling
>> and becoming an adiabatic expansion whcih would be less efficient as
>> the cold air has less pressure and volume.
>>
>> It's the same story in reverse where compression efficiency is kept
>> high by the same process.
>>
>> They are managing to store some 46MJ or 12.77kw.hr in their 3 x 30
>> cubic meter 300 bar compressed air tanks. Cars use approximtely
>> 10kw.hr/ton/100km and on the basis of the stated range of the car and
>> its weight the efficiency of the car must be around 80%. Compression
>> would also be around 80% efficient.
>>
>> This is competitive with batteries.
>>
>> If you follow the links on these sites and you open open your closed
>> mind you might become englightened.
>>
>> http://www.theaircar.com/howitworks.html#
>> http://www.theaircar.com/ficha.html
>>
>> Not they have disclosed the motion and even have an animation of it.
>>
>> All of their sums check out!
>
>Then I am sure you will want to invest heavily in them.
>
>Meanwhile, I still believe that the energy density of compressed air is
>uselessly low.

  Well, I can see why you still have that mistaken belief, Don. :-)
  It says very clearly at that first web site above that:

  " The CAT´s 34 P04 engine is equipped with patented variable-volume
butts and a dynamic variable-volume volumetric reducer."

Anybody knows that with variable-volume butts,
entropy is conserved. :-)

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