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Old 04-06-2009, 09:26 PM   #11 (permalink)
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All I have to say is "LOL".

Sometimes, the stupid people are necessary. Most of the time, they're a burden. (When they're necessary, it's only to make the marginal seem intelligent enough to pass for a smart person... i.e. elections.)

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Old 04-06-2009, 09:42 PM   #12 (permalink)
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It's actually probably dumb in alot more weighs than the obvious. For instance we know very well what happens when we burn fuel at atmospheric concentrations and o2 rich concentrations. . .but there are not very many experiments with hydrogen at high temperatures mixed in. It might make the engine more brittle because thats what happens when water breaks apart in your cylinder(vapor in Atmo concentrations. . .obviously if you dump water its thermal stress cracking.)

But hey if you have a way to get small amounts of juice for "free" and can store the created H2 and O2 safely till you wanna use it go ahead. . .Keep in mind its going to be alot like nitrous. . .
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Old 04-06-2009, 09:45 PM   #13 (permalink)
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I have a set of plans for one of the devices in question, but only for something to play with on a personal level, and I"ll probably never actually build it.
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Old 04-06-2009, 09:53 PM   #14 (permalink)
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I HAVE one. . .but I was going to run it off a set of low wattage SEs. Until I tested the amount of gas they would be producing and at a locked throttle position RPM didn't even wiggle.

Which, um is the subject of some interest since the ICE-SE e motor concept floundered rather miserably. . .
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Old 04-06-2009, 10:17 PM   #15 (permalink)
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I have trouble believing you could extract a useable volume of hydrogen to run a vehicle with a simple solar panel in a reasonable amount of time and then you'd need to compress it for storage. It certainly wouldn't produce enough to power it on the fly! I'd need to see some very convincing math to think otherwise.

On a vaguely related note, water injection is sometimes used on highly turbocharged engines to cool the cylinder temps down.
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Old 04-06-2009, 10:47 PM   #16 (permalink)
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Over the course of this discussion I seem to have mixed two topics up. One a man powered a car on hydrogen from a cylinder. a second man supplemented his car by adding hydrogen directly to the intake(think like a dry shot of nitrous) along with regular air and gasoline. outcome of 2 was his engine ran a touch lean because it was expecting the H2 gas to be air containing some O2. . .but there was alot more O2 in it than expected.

You are dead straight. The guy had a truck and the entire back was covered with PVs and he only saw low improvements. He then used them on his house(original intent).

The only. . I guess advantage you could call this system is a go-between poor mans hybrid. It gives you a little boost during the day like a hybrid does all the time, but its not really cheap. I mean if you can get solar panels free then yes it is(I watch for unattended solar fountains and highway signs, just kidding).

The other problems are most cars don't have any good surface area for this. Your roof and trunk are usually the only good places to put pv(hood can get too close to thermal max once you stop moving and shut it off). That said slapping them on the roof of your box truck or minivan will at least annihilate the parisitic drag of the AC and power steering and otherelectric functions. If you still have juice you now know what to do with it.

A while back I posited the idea of using the exhaust heat to run small Stirling engines and have both of them generate electricity and then just use electric motors(gets the immediate efficiency of ICE combined with the max efficiency of SE as a two stage system(more efficient than one phase between the same two resevoirs)).

Needless to say there are too many conversions mentioned above that misplace energy. My considerations have somewhat abandoned SEs for the time being, but this one is still lurking out there.

The problem with the water for fuel is you are taking fuel converting it to useful work and converting it to fuel and then useful work. Energy cannot be created or destroyed but it frequently goes places you don't want it to(friction and under your window sills). converting always loses energy when mechanical work is involved and thats exactly what they saw when they turned the unit on. the alternator seeing a large draw and inefficiently converting work to electricity and then inefficiently covnerting water to H2-O2 and then inefficently burning air,H2-O2 and Iso-Octanyl.

Using an SE downstream from the engine along the exhaust you have a 400 degree temperature difference and the possibility of work, without being parisitic to the engine(It will cause slightly more backpressure on the engine as the air cools and decelerates to density increases but thats pretty negligible). If you draw 3 HP out of the SE, convert H20 to H2-O2 and then burn it your engine is getting 2 HP "free." Not really free, but its energy that you had previously decided was worthless.

Problem currently faced is no one manufactures an SE of this size. SES builds pretty huge 25 KW SEs that run on a 650 degree difference and there are toys. Nowhere in between.

Last edited by theunchosen; 04-06-2009 at 11:00 PM..
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Old 04-07-2009, 03:32 PM   #17 (permalink)
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There are 2 things that must be realized to sum up:

A: As said above, producing hydrogen using the power from your car isn't going to increase mpg, it should decrease it. You don't get more power out of burning the hydrogen cracked out of water than it takes to do the "cracking".

B: Hydrogen can be produced at home, stored, and used in a vehicle. To have any range, it must be stored at a high pressure and then you have a H-bomb on wheels.
Imagine the scene of an accident..."were waiting for forensics to arrive to get particles from the crater so we can find out who hit who".
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Old 04-07-2009, 05:30 PM   #18 (permalink)
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Quote:
Originally Posted by rkcarguy View Post

B: Hydrogen can be produced at home, stored, and used in a vehicle. To have any range, it must be stored at a high pressure and then you have a H-bomb on wheels.
Imagine the scene of an accident..."were waiting for forensics to arrive to get particles from the crater so we can find out who hit who".
totally agree with the first part.

The second part. . .It's only as dangerous as rupturing your fuel tank. Most likely what would happen is a valve would snap off the tank causing it to accelerate in whatever direction the valve was.

Hydrogen is very energetic and much lighter than air, not like propane, methane or iso-octanyl. The hydrogen once its out of the tank would rapidly expand and no longer be dense enough for combustion. Seriously try getting some to burn more than a few inches from a small outlet.
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Old 04-07-2009, 06:16 PM   #19 (permalink)
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Quote:
Originally Posted by theunchosen View Post
totally agree with the first part.

The second part. . .It's only as dangerous as rupturing your fuel tank. Most likely what would happen is a valve would snap off the tank causing it to accelerate in whatever direction the valve was.

Hydrogen is very energetic and much lighter than air, not like propane, methane or iso-octanyl. The hydrogen once its out of the tank would rapidly expand and no longer be dense enough for combustion. Seriously try getting some to burn more than a few inches from a small outlet.
Actually a large hydrogen leak can be very dangerous. It will escape from a pressure tank and form a huge combustible cloud in a short amount of time before it has a chance to disperse. Hydrogen has a lower explosive limit of 4% and an upper explosive limit of 75%. This wide range of flammability and its rapid combustion speed can result in quite a powerful explosion.

All the big car companies that are experimenting with hydrogen vehicles use metal hydride hydrogen tanks. The reason is it prevents the hydrogen from being released quickly in case of a storage tank breach. This provides time for it to disperse or burn off slowly.
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Old 04-07-2009, 08:43 PM   #20 (permalink)
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Quote:
Originally Posted by ConnClark View Post
All the big car companies that are experimenting with hydrogen vehicles use metal hydride hydrogen tanks. The reason is it prevents the hydrogen from being released quickly in case of a storage tank breach. This provides time for it to disperse or burn off slowly.
They actually use them because its easier. Its what the aircraft companies have been doing for years with oxygen. The reason is the hydride is MUCH lighter than any tank. Even if we ignore safety completely the pressurized cylinder that would be needed to hold that much H2 would weight a ton.

Scuba tanks rated up to a few thousand PSI only hold 60-100 ft^3 of air(not very much fuel) and they weigh in around from 25-50 lbs dry. Multiply that by 10 times or so to get a decent amount of fuel and you weigh four times more than my gas tank. OR as much as my gas tank and engine for just the fuel.

H2 does have a very high dispersive rate. Its collisions are much more elastic than as I mentioned methane or propane. a LEAK would be very dangerous yes because it would be a much more controlled pressure release than the tank being ruptured. I've been in the shop when H2 tanks and O2 tanks are dropped and its pretty nerve racking to see it coming.

Whenever high-pressured vessels rupture from a high energy impact(car collision, bullets, dropping a substantially heavy enough object on them) the pressure can force massive crack propogation. If and when they break they go in in a big way. Leaks usually occur at the valves or seems and are caused by fatigue.

Seriously try to light a stream of H2 coming out something the size of a welding torch from 3 inches away from the nozzle. Not happening. Oxyacetlyne Will do it just fine, propane and methane will do it to. Its why they use hydrogen in High Energy heat engines because it very quickly converts energy to movement(pressure).

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