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H2 Combustion-Booster Claimed



 
 
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  #11  
Old September 20th 05, 04:59 PM
Harry Andreas
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In article , Bryan Martin
wrote:

Lets see. You take energy from the electrical system to crack water into H2
and O2. Then you pipe the H2 into the engine with the gasoline where it will
combine with oxygen to form water. The article I read doesn't say what you
do with the O2, I guess you just vent that to the atmosphere. Seeing as how
conversion of water into H2 and O2 is not 100% efficient due to losses in
the wiring and such and seeing as how burning H2 with air is also not 100%
efficient, there is no possible way to get a net energy gain out of this
system. In fact this system will result in a net loss and lower fuel economy
since the electrical energy to drive the electrolysis must come eventually
from the alternator which is driven by the engine.


That's the Second Law of Thermodynamics: in ANY energy conversion scheme
there is inefficiency and therefore loss.


The only way to get any kind of gain out of this is to inject the water
itself into the engine. This might give some power gain in the short term
but pumping salt water into your fuel system and engine will certainly do
them no good in the long run. The article specifically mentioned putting
water and an electrolyte (salt) into the booster tank.


Agree on the salt.
Water injection only works to increase power if you increase engine
compression. The higher compression ratio gets you more power, the
water injection cools the charge and acts like an octane booster.
Just don't run out of water...
If you run water without increasing compression ratio, you will get a little
due to the density increase of the air, but it's not major.

--
Harry Andreas
Engineering raconteur
  #12  
Old September 20th 05, 06:25 PM
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Harry Andreas wrote:
In article , Bryan Martin
wrote:

...


The only way to get any kind of gain out of this is to inject the water
itself into the engine. This might give some power gain in the short term
but pumping salt water into your fuel system and engine will certainly do
them no good in the long run. The article specifically mentioned putting
water and an electrolyte (salt) into the booster tank.


Agree on the salt.


Someone else wrote that it was KOH that was added, not a salt.
Dunno why, if it was just a water injection system. Would the
KOH help to control NOx emmissions? Could the KOH be threre
for boiling point elevation?

Water injection only works to increase power if you increase engine
compression. The higher compression ratio gets you more power, the
water injection cools the charge and acts like an octane booster.
Just don't run out of water...


If you are injecting atomized (e.g. liquid) water into the
cylinders then during the power stroke the water will
evaporate. That evaporation converts heat to pressure at
constant temperature. You get a higher compression raio
without a higher temperature. Does THAT help to control NOx,
in addition to giving you more power?

If you run water without increasing compression ratio, you will get a little
due to the density increase of the air, but it's not major.


IIUC, adding the water will increase the compression ratio
due to the phase change of the water. Water injection increases
the compression ratio without changing the geometry of the cylinder
and piston, right?

--

FF

  #14  
Old September 20th 05, 07:06 PM
Capt. Geoffry Thorpe
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Water can reduce the charge termperature as it evaporates in the cylinder
which can increase the charge mass a little, but mostly it improves knock
resistance by cooling the charge and increasing the specific heat of the
charge mass. But to really take advantage you have to either increase the
compression ratio or boost.
NOx is recduced somewhat since the peak temperatures are reduced.

If you are trying to change the fuel chemestry to get more energy out - you
have to put energy in. Lose - lose.

If you are trying to make the fuel burn "better" to make it "all" burn -
gasoline burns just fine. Unburned fuel in the exhaust comes from three
primary sources - mixture that is pushed into the crevices around the piston
/ sparkplug / etc. where it can't burn (it comes out of the crevices during
the exhaust stroke), mixture that is quenched at the cylinder walls due to
heat loss. And excess fuel from running rich. The bulk of the charge mass
burns just fine. Cow magnets, magic additives, whatever aren't going to
change any of that.

If making the fuel burn "better" made it burn faster - Well, if it really
worked all you would do is destroy the engine because the faster combustion
would result in detonation.

--
Geoff
the sea hawk at wow way d0t com
remove spaces and make the obvious substitutions to reply by mail
Spell checking is left as an excercise for the reader.


  #15  
Old September 21st 05, 01:22 AM
Harry Andreas
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In article , "Capt. Geoffry
Thorpe" The Sea Hawk at wow way d0t com wrote:

Water can reduce the charge termperature as it evaporates in the cylinder
which can increase the charge mass a little, but mostly it improves knock
resistance by cooling the charge and increasing the specific heat of the
charge mass. But to really take advantage you have to either increase the
compression ratio or boost.
NOx is recduced somewhat since the peak temperatures are reduced.

If you are trying to change the fuel chemestry to get more energy out - you
have to put energy in. Lose - lose.

If you are trying to make the fuel burn "better" to make it "all" burn -
gasoline burns just fine. Unburned fuel in the exhaust comes from three
primary sources - mixture that is pushed into the crevices around the piston
/ sparkplug / etc. where it can't burn (it comes out of the crevices during
the exhaust stroke), mixture that is quenched at the cylinder walls due to
heat loss. And excess fuel from running rich. The bulk of the charge mass
burns just fine. Cow magnets, magic additives, whatever aren't going to
change any of that.


Actually, ( I was trying to make it simple ) either compression or boost can
be expressed as as BMEP, which takes both into account.
As BMEP rises you get better combustion of any unburned fuel from being
too rich (not a factor in today's autos) , but the higher pressure also
suppresses
the boundary layer at the cylinder wall, giving better combustion there also
and lower unburned hydrocarbons as a result.
Using water injection, as you say, allows you to increase BMEP without
risking knock because it cools the intake charge, acting (as I said) like
an octane improver.

--
Harry Andreas
Engineering raconteur
  #16  
Old September 21st 05, 03:35 AM
Big John
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B-26K with R-2800 engines could pull 2500 HP with water injection.
I've got 150 hours in bird.

Think some if the 'Jugs' had water and could pull 90 inches with the
water getting 2800 HP in late models.

Big John
`````````````````````````````````````````````````` `````````````````````````````````````````````````` ```````

On Mon, 19 Sep 2005 22:14:20 -0700, Charlie Springer
wrote:

On Mon, 19 Sep 2005 00:03:47 -0700, wrote
(in article . com):

It sounds reasonable that injecting H2 into your fuel stream can
improve the combustion. I assume that combusting the H2 in your
cylinders along with the regular fuel will boost temperature to give a
cleaner burn. Would the higher temperature harm your engine life at
all?


Don't know about a cleaner burn. Higher temperatures mean mire nitrogen
compounds. In fact, a pure H2 and atmosphere engine will produce the nitrogen
compounds that make up smog. To be clean, you need a pure O2 for oxidizer,
not air.

The fuels we use are hydrocarbons and there is plenty of hydrogen there
already. In a perfect burn, as in stoichiometric combustion with O2, all you
get from gasoline is water and CO2. Octane is just 8 carbons surrounded by 18
hydrogens. Adding hydrogen and decreasing gas might get a hotter fire, but we
run about as hot as we need (or can stand) now for long engine life. Hotter
might help prevent oddball bits of hydrocarbon from being unburned (handled
by catalytic converter) but increase NO2, etc.

The link didn't lead to whatever you saw, so I can't comment on the thingy.
It probably works as well as putting magnets on your fuel lines.

-- Charlie Springer


  #17  
Old September 21st 05, 03:34 PM
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Capt. Geoffry Thorpe wrote:
Water can reduce the charge termperature as it evaporates in the cylinder
which can increase the charge mass a little, but mostly it improves knock
resistance by cooling the charge and increasing the specific heat of the
charge mass. But to really take advantage you have to either increase the
compression ratio or boost.
NOx is recduced somewhat since the peak temperatures are reduced.

If you are trying to change the fuel chemestry to get more energy out - you
have to put energy in. Lose - lose.

If you are trying to make the fuel burn "better" to make it "all" burn -
gasoline burns just fine. Unburned fuel in the exhaust comes from three
primary sources - mixture that is pushed into the crevices around the piston
/ sparkplug / etc. where it can't burn (it comes out of the crevices during
the exhaust stroke), mixture that is quenched at the cylinder walls due to
heat loss. And excess fuel from running rich. The bulk of the charge mass
burns just fine. Cow magnets, magic additives, whatever aren't going to
change any of that.


Ah but the thermodynamic efficiency of a heat engine increases as
the compression ratio or temperature ratio increases. The issue
is not how to get more heat out of the fuel, it is how to convert
more of the heat to mechanical energy.

--

FF

  #19  
Old September 23rd 05, 04:19 PM
Mike Rapoport
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Water injection does not increase efficiency, it lowers it. The water goes
in as a liquid and goes out as a gas. The energy to do that comes from
burning fuel. It will always take more fuel to produce a given amount of
power with water injection than without. Water injection does allow higher
MP or higher compression so the engine can produce more power. Piston
engine fighters used it for more peak horsepower and some turbines use it
for the same purpose but it definately come at the price of higher fuel burn
per horsepower.

Mike


"Jeff" wrote in message
...
Some fellow is claiming he has a small device that will boost
combustion efficiency and save drivers lots of money, while reducing
emissions.

Obviously, plenty of claims have been made before, so I'm asking --
does this sound on the level?


Water injection has been around for a long time, both for internal
combustion and aircraft jet engines, it does improve efficiency, reduce
temperatures and reduce some emissions. It depends what is being claimed
for the actual device.

Regards
Jeff



  #20  
Old September 23rd 05, 07:29 PM
Bill Daniels
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"Mike Rapoport" wrote in message
ink.net...
Water injection does not increase efficiency, it lowers it. The water

goes
in as a liquid and goes out as a gas. The energy to do that comes from
burning fuel. It will always take more fuel to produce a given amount of
power with water injection than without. Water injection does allow

higher
MP or higher compression so the engine can produce more power. Piston
engine fighters used it for more peak horsepower and some turbines use it
for the same purpose but it definately come at the price of higher fuel

burn
per horsepower.

Mike


Hmm, consulting my ancient copy of Ricardo's "High Speed Internal Combustion
Engines", Sir Harry said that water injection can be substituted for any
excess fuel consumed for the purpose of reducing cylinder temperature and/or
increasing detonation margin. Further, evaporation of the water reduces the
intake charge temperature so as to reduce pumping losses. He goes on to say
that, while there is energy lost to evaporating the water droplets, the
overall fuel economy of an aircraft engine at max power setting will be
improved by use of water injection particularly if the compression ratio has
been increased to take advantage of the increased detonation margin.

Bill Daniels

 




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