Quote:
Originally Posted by john_bud
Uh...no. When I hit the gas peddle, there is a slight lag in the air motion, but it is VERY slight. In a carburated engine, the FUEL is the stuff that lags and quick stabs of the throttle result in lean misfire unless a quantity of fuel is squirted in. The engine is operating at a vacuum and there is a large force pushing the air into the cylinders from that vacuum. In a hydrogen generation system, the hydrogen has to be cracked from water. That takes time for the reaction to occur, time to heat the water to allow the reaction to be efficient, time for the partial pressure of the gas in the liquid to build, time for bubbles to form, time for the bubbles to raise to the surface and pop, time for the gas to traverse the distance from the generation system thru the tube to the manifold. That time is in seconds - whole seconds and typically in the 3-10 range depending on the system status. Just put a potentiometer on a system and go from 1 amp to 20 amps and see how long it takes.
|
The hydrogen production in an electrolyzer is directly proportional to the current flowing through the system. The current can vary from 0 to full current very very quickly. Technically speaking the current would probably rise as some sort of 2nd order damped system, but the time constant on such a system would be on the order of miliseconds. There would be some delay for the pressure to rise, but it wouldn't be terrible either. Pressure propagation at room temperature is typically around 600 km/hr.
Quote:
Originally Posted by john_bud
The other side of that is also there. You can't instantly STOP hydrogen/oxygen generation. I for one don't want to slam on the brakes and have the engine still supplied with loads of combustible gas + oxygen! Because the quantity of dissolved gas in the reaction fluid would be huge if you had to reach 20%. Sure, a 5% target would be better, but still the issue remains. Naturally, no systems take that into account as they are not capable of generating enough gas.
|
When current stops flowing through the electrolyzer, hydrogen production stops instantly. The only overshoot would be whatever hydrogen was still bubbling out of the water, and i can't imagine that would be a terrible lot. In any case, to much hydrogen wouldn't hurt anything, and wouldn't cause any significant over run. We're not talking about enough hydrogen to even keep the engine at idle, never mind run away.
Quote:
Originally Posted by john_bud
Speaking of percentages... I thought I made it clear that my numbers were made "easy" to make the math simple. Even at 5% hydrogen a small 4 cylinder engine needs an astronomical volume of gas. While most may spend the majority of the time at 30% throttle, should we ignore the system's requirements for idle ? acceleration ? Higher rpms? I run less than 30% most of the time, but do run 100% on occasion and 50-70% frequently to go from stops or to merge on the freeway.
|
Hydrogen Fuel Enrichment is only useful at lower loads. At higher loads you WANT to run at stoich, and as such, you wouldn't design you system for these conditions.
Quote:
Originally Posted by john_bud
Your last point was that you can make hydrogen "in a millisecond" by using "electronics". I call BS on that and ask you to provide some factual proof. While I don't know everything, I do know that chemical reactions like this are not digital! And yes, I HAVE diddled around with electrolysis, chemical reactions and even electronics.
|
I think i've already addressed this, but I'll say it again:
Hydrogen production is proportional to current. If you run 100 amps through an electrolyzer, it's production is instantly going to be 100 amps worth of hydrogen.
I think what you've been playing with has been much much smaller scale, and you've been seeing bubbles starting to form, and nothing heads to the surface immediately, giving you the impression of delay. But then, you were probably running very small current amounts. A properly designed system would be able to fire up and have full production nearly instantly. A real automotive system would probably have to throw down nearly a kw to achieve enough hydrogen production.
But I do think it's not a really effective solution. Existing lean burn engines and atkinson engines offer similar gains with less fuss. And as has already been pointed out, these are all band-aid solutions to the problem of engines that are too large.
Bring on the 200 CC turbo engines please. Preferably Diesel.