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Old 12-04-2007, 11:39 PM   #31
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Re: Hydrogen inside Air Intake increases Gas Mileage?

Hydrogen isn't an energy source, it's simply a storage medium. Just like a battery.

If hydrogen can provide a greater energy density than a competing battery then it'll become widespread. If it can't then it'll remain the source of urban myths and legends. Just like the 100mpg carburettor.
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Old 12-05-2007, 01:23 AM   #32
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Re: Hydrogen inside Air Intake increases Gas Mileage?

Quote:
Originally Posted by texan
mikasf- You are spamming this site with nonsense, therefore you are banned.

Now thats a come back!

So where have you been hiding Tex?
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Old 12-05-2007, 12:40 PM   #33
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Re: Hydrogen inside Air Intake increases Gas Mileage?

Quote:
Originally Posted by KiwiBacon
You can break even if you get to 0 degrees kelvin.
But getting there is a problem.

Thanks to the mod who banned that muppet.
To that i say, It's impossible to get to 0*K, so nyah! We've gotten close that. The best way is to find my ex and stick a thermometer in her heart when you mention my name
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Old 12-05-2007, 01:20 PM   #34
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Re: Hydrogen inside Air Intake increases Gas Mileage?

Quote:
Originally Posted by Moppie
Now thats a come back!

So where have you been hiding Tex?
Oh, here and there. It's been a couple of years though hasn't it? I still pop in here once in a while, I just usually don't find anything to post to.
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Old 12-05-2007, 06:20 PM   #35
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Re: Hydrogen inside Air Intake increases Gas Mileage?

Quote:
Originally Posted by Steel
To that i say, It's impossible to get to 0*K, so nyah! We've gotten close that. The best way is to find my ex and stick a thermometer in her heart when you mention my name
Now that's cold.
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Old 12-05-2007, 11:08 PM   #36
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Re: Hydrogen inside Air Intake increases Gas Mileage?

Quote:
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Oh, here and there. It's been a couple of years though hasn't it? I still pop in here once in a while, I just usually don't find anything to post to.

I'm spending less time in here to, especialy since getting a Prelude. The damn things is as reliable as it is boring.
Have you bumbed into Fritz in your travels? I lost contact with him after PH shut down.
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Old 07-20-2009, 12:13 PM   #37
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Re: Hydrogen inside Air Intake increases Gas Mileage?

I realize that this is a dead thread, but I wanted to make a couple of points.

1) Themodynamics tell you that the combustion cycle is NEVER 100% efficient. In fact, there is about 2-3x more chemical energy consumed than the mechanical energy output by the engine.

2) Electromagnetics tells you that it is a practical impossibility for 100% efficiency in converting that energy to electricity.

3) It has already been mentioned that electrolosis is not even close to 100% efficient in breaking the energy bonds of the hydrogen and oxygen in the water. It's true that hydrogen and oxygen store the energy "chemically" until the hydrogen is burnt and returned to a water molecule. However, the conversion to mechanical energy is subject to the same thermodynamic limits (~30%) due to the combustion cycle.

4) Hydrogen is not necessarily the best way to store energy. While it is advantageous from when measured as stored energy per unit mass (i.e J/kg), it is not advantageous when you consider the stored energy per unit volume, even if you use liquid hydrogen. In addition liquid hydrogen requires a very heavy storage tank due to it's volitility and the extreme vapor pressure at ambient temperatures (i.e. easily over 1000 psi at temperatures up to 50 deg C).

In conclusion, if you burn 1 Joule of fuel to create 0.3 J of mechanical energy, then convert that to 0.25 J of electricity that is then used to store 0.1 J of chemical engergy stored in they hydrogen, you've just lost 0.9 J of energy to get back to where you started.

Hydrogen is also less safe than other fuels such as gasoline and kerosene. Both of these fuels are diffcuilt to ignite when compared to hydrogen. Gasoline will only burn when the air/fuel mixture is within a very narrow range, something like 5%-10%. However hydrogen will combust over a very wide range (4%-70%), making leaks very dangerous. Hydrogen flames are not normally visible. Further complicating hydrogen saftey is the fact that metal exposed to hydrogen becomes brittle. Because hydrogen is the smallest atom, it will diffuse through any other material used to contain it. Just as a helium ballon deflates over time as the helium leaks between the rubber molecules of the balloon, hydrogen will diffuse through any containment material, requiring new safety precautions in tankers and pipelines that carry it. Of course, since hydrogen is a gas at standard temperature and pressure conditions, tank ruptures cannot be contained, and any ignition of a leaking containment will often result in explosive combustion of the hydrogen, although this danger is somewhat reduced since leaks will be more likely disburse since hydrogen is lighter than air.

Given these facts, not only is it wasteful and counterproductive to install a hydrogen device in your car, it's potentially dangerous if the device is actually capable of producing significant hydrogen.
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Old 07-21-2009, 08:31 PM   #38
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Re: Hydrogen inside Air Intake increases Gas Mileage?

I fully agree on all points, and you bring up some very good tech.

But... I'm going to close this one because this is a thread I don't want coming back to haunt me

But... I'm also making it a sticky so it hangs around long enough for folks to read.
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