Humidity

[Robert Harris]

Water, used in more than a modest amount, has the unfortunate tendency to 
absorb more heat from the combustion process than it returns in increased 
expansion of the working gasses.  This means that except for countering other 
bad things, water generally does no good.  The increased humidity - increased 
power effect most people observe is probably the reduced temperature induced 
air density increase. For most engines the pressure should peak about 15 
degrees and by about 20 after top dead center the fire is out.  The only hope 
for "free" energy that I can see is to inject water a la diesel directly into 
the chamber at about this time.  Most of the convertible heat has been utilized 
by then and adding excess water will simply result in increased pressure 
without affecting the combustion process.

After having been "steamed" into submission for my unorthodox beliefs that 
excess thermal energy may be recovered by other means, I still remain convinced 
that water used as an expendable working fluid can recover significant power 
without violating any generally accepted principles - only now the mechanism 
has to be more elegant than simply pissing into the intake.



If the first ingredient ain't Habanero, then the rest don't matter.
Other Obsessions: Ferro-Equinary , 1972 "Killer Whale" Mustang
Robert Harris <bob at bobthecomputerguy.com>


-----Original Message-----
From:	Michael T. Kasimirsky [SMTP:mtk at tmc.astm.cmri.cmu.edu]
Sent:	Tuesday, September 23, 1997 11:56 AM
To:	diy_efi at coulomb.eng.ohio-state.edu
Subject:	Re: Humidity

On Tue, 23 Sep 1997, Charles Fulton wrote:

>
>
> Michael Skolones wrote:
>
> > I'm afraid there's an energy conservation problem in this hypothesis.  The
> > energy produced by the hydrogen/oxygen combustion will be equal to the 
energy
> > required to split the water molecules into hydrogen and oxygen in the first
> > place. The net energy change due to this water combustion cycle will be 
zero.
> > Mike Skolones
>

>True it does take energy to split the Hydrogen and Oxygen but we must
>remember that an internal combustion engine is not even close to 100%
>efficient or else the exhaust wouldn't be any hotter than the air going
>in.  So why couldn't some of the otherwise wasted heat be used to break
>down water and reuse the components in a more productive way.  We don't
>violate conservation of energy with this just convert otherwise unused
>energy into a useable form.  Water injection is a proven method as is
>nitrous, and there are plenty of guys to tell you that nitrous makes more
>power.

Water injection is used to reduce detonation by reducing intake charge
temperature.  It won't give you more power in it's own right.  It can be
used to make more horsepower since it allows you to run additional boost,
different ignition timing, etc.

Splitting water into hydrogen and oxygen and then recombining them will
result in a net zero energy release in a perfect world.  Since we don't
live in a perfect world, there will be losses.  Breaking and recombining
water will be a net energy loss, every time.

The first law of thermodynamics is, in a nutshell, 1) you can't win, 2)
you can't break even, and 3) you can't quit.

Look at it this way: if simply injecting water into the engine would give
you more power, every car for sale on this planet would be equipped with
water injection from the factory.  No one would pass up this "free"
horsepower, since it would improve fuel economy, performance, etc.

Nitrous oxide also works by both cooling the intake charge as well as
breaking down into N2 and O2, giving more oxygen to react with the
additional fuel injected with the NO2 gas.  If you don't add additional
fuel with nitrous, you won't get more power, you'll get melted motor
parts.


Michael T. Kasimirsky       ---->              mtk at tmc.astm.cmri.cmu.edu
Days:    Staff Engineer                     or mk4u at andrew.cmu.edu
         ASTM Test Monitoring Center           Phi Gamma Delta,
Nights:  1992 Suzuki GSX-R750 Pilot            NRA Life Member, AMA Member
         1990 Yamaha FZR400 Superbike Racer    DoD #1848
         1991 Suzuki GSF400 Bandit Mechanic    WERA Novice #753