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Old 05-29-2009, 12:07 PM   #11 (permalink)
theunchosen
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Quote:
Originally Posted by jason.thompson View Post
theunchosen,

I see your perspective and in it your right. Now let me unload some hydrogen propaganda.

The idea of getting your electricity from a source outside the engines crankshaft might help open up hydrogen generators. Considering today's engines produce just as much waste heat as they do work at the wheels.

First of all we need to get on the same page.

Most vehicles have only 25% thermal efficiency. Side note: I don't understand why people use MPG as a way to measure efficiency. You are making more work for yourself. Also I want to pick on ecomodder's mission statement. You guys are not concerned with power? Power is what does work. Fuel efficiency is a result not a goal.

So the unchosen, your example works if our engines were 100% thermal efficient. It is not so simple. Take today's diesel engines which have particulate matter filters. The engine dumps fuel to burn out the ash. A cleaner burning engine requires less fuel dumps. A gasoline engine uses fuel to cool combustion. So why not substitute water+methanol or steam? But I think for gas 3-way-cats to work they need rich 14.7 to 1 fuel mixtures. So leaning them out which you can do with hydrogen might make them not work?

I'm not saying go out and buy anything. It's kind of like this pretend on-board hydrogen generators are a rare species of ants. These ants secrete a liquid which cures cancer. Here I am on my hands and knees with a magnifying glass carefully working to not squish anything which might be under a leaf or twig. Here you are running around screaming at the top of your lungs looking towards the sky and truly believing cancer curing ants couldn't possibly exist.
Thats not really at all what I am doing. What I am telling you is just that. . .running hydrogen as fuel gets the exact same efficiencies as running gasoline. It doesn't change.

Its very easy to test whether the hydrogen does something. Put a hydrogen gas tank in your car and feed the line in after the throttle body near the intake manifold.

In that situation the hydrogen as far as the rest of the car is concerned is free. The result is minimal FE increase flowing enough hydrogen to maintain a pilot light(Good luck getting that out of any electrolysis system you can buy for less than 1 grand). If you twist the valve more and let it run pretty wide open FE changes alot.

Thats because you're dumping in sub 0F coolant and a ton of extra fuel.

Moral of all hydrogen testing is unless you've got a compressor that can handle slowly compressing the hydrogen to avoid detonation and you can do it for free(solar or whatever) running hydrogen in your car is pointless.

The only place anyone has encountered any FE improvement for fuel cost is in ultra-lean gassers running hyper 35:1 AFR. In that case it improved FE because it encouraged the flame front to travel faster as it hit the H2 pocket avoiding the flame dying out in the chamber(encountering pockets of 140:1 AFR when the chamber is running too lean the AFR is not homogenous by any means).

Once again unless you have "free" electricity that the engine is not using in any way shape or form using one of these generators is a waste of your fuel.

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