Hydrogen Generator Experiment

[stevey_frac]

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.

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.

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.

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.

[tjts1]

Originally Posted by stevey_frac

This is wrong though. They tested the kits. The kits provably don't work.

But hydrogen fuel enrichment that enables a lean burn engine to run very lean at low loads is more efficient. Provably so. The kits just don't have the sophistication to lean out the AFR. To do it properly, you'd have to add a wideband O2 sensor, and trick the ECU into running quite lean if the load was low.

Better yet would be to have a wideband, and an ECU with lean cruise built in.


Need proof? Check out this study:

ScienceDirect - International Journal of Hydrogen Energy : Hydrogen enrichment for improved lean flame stability

(i hope that link works)

Alternatively, do a google search for hydrogen fuel enrichment.

Well if you think you've invented a magical free source of hydrogen that doesn't require any energy, I'm sure we would all love to heard about it. Until you do, any benefit gained from the hydrogen will be more than made up for by the additional alternator load. Sorry buddy but there is no free lunch here. Please check your spelling.

Originally Posted by stevey_frac

The same thing happens when you hit the gas peddle on you car with respect to air. There is no magic device that allows the air in the intake manifold to suddenly jump from 5 psi to 14psi (MAP reading). As a result, the AFR dosent' perfectly track at 14.7:1. It wanders. Richens up when you punch the peddle, leans out when you suddenly let off. That's fairly normal, and the same would be acceptable in a hydrogen system.

You need to read up on EFI or better yet build an EFI system before you start saying things like this. You have no idea what you're talking about.

[stevey_frac]

Originally Posted by tjts1

Well if you think you've invented a magical free source of hydrogen that doesn't require any energy, I'm sure we would all love to heard about it. Until you do, any benefit gained from the hydrogen will be more than made up for by the additional alternator load. Sorry buddy but there is no free lunch here. Please check your spelling.

Small amounts of hydrogen improve the thermodynamic efficiency of the gasoline engine by allowing lean burn flame stability to be extended. Lean burn at lower loads improves BSFC of the engine. This is not a second law of thermodynamics violation. This allows the engine to run at a higher effiency, extracting more power from the gasoline. It does not make free energy from the hydrogen. Go read up on hydrogen fuel enrichment. Not the kits. The science. The kits are garbage. I've said as much. There has been a lot of work done fairly recently that shows that hydrogen reduces peak cylinder temperatures, reduces NOx production, and reduces HC emissions.

Originally Posted by tjts1

You need to read up on EFI or better yet build an EFI system before you start saying things like this. You have no idea what you're talking about.

What i'm talking about is referred to as controller overshoot and undershoot. There is no perfect controller. Even with the best smith predictor (look it up) and the most optimally tuned PID controller, when you change the operating conditions, it won't track perfectly.

Furthermore, the intake manifold can't be treated static, or even linear pressure system. It's going to vary as at least a second order system, with the inertia of the air coming in (similar to inductance) and the volume of the air in the manifold at any given (similar to capacitance).

Current computers don't solve this equation and predict the exact amount of fuel at this instant required.

The current manifold intake temperature is X, and the current RPM is Y, therefore this is the amount of fuel required. Then they apply a half dozen modifiers to it for coolant temp, intake air temp, and fuel trims as determined by the O2 sensor.

I would actually say I know a fair bit about controllers and EFI.

And I apologise for my speellling.

[Nerys]

ahh I have not done this yet (no time no money) but I may give it another go now that I have a metro to play with.

the solution seems pretty easy to me. the problem is NOT energy. Energy is not really relevant. the problem is MONEY. how much does that energy cost you.

so the solution seems easy to me. DO NOT power they HHO generator off the engine.

power it off a battery pack and use your silly cheap (compared to gasoline) electricity at home to recharge the battery pack.

when and or IF I get around to trying this that is how I am going to do it. 3 deep cycles in the boot with the HHO generator.

[Christ]

Why wouldn't you just save the space and weight in the car, and generate the HHO at home, then store it and use it in the car? You'd get better overall fuel efficiency that way, since you're not carrying around a generator and a few deep cycles.

[Frank Lee]

Your time would be better spent whittling a wooden chain out of a 16' plank.

But hey, it's your time.

[Christ]

Me, I prefer teaching my infant to hold his own bottle...

[Nerys]

well the problem is generating HHO is easy. STORING HHO is not so easy. Hydrogen is a very frisky little atom. it leaks from EVERYTHING including steel tanks.

then you have the problem of COMPRESSING it. take a weather balloon you know those 16foot rubber balloons that will fill an entire room of your house? fill it with HHO. that MIGHT be enough to suppliment your car for 15 minutes. See the problem. the only way to do this is to generate in real time or to COMPRESS it into a storage tank. Compressing it is VERY expensive.

I know HHO can work. its only logical. you insert more fuel you go further. its just that simple. The question is NOT if it works. The question is is it EFFECTIVE or PRACTICAL

ie can you generate ENOUGH HHO to make a difference you can measure? if it does not give me at least 5mpg then its likely not worth it to me.

its not really a loss. I already have the 5gallon pail I am going to use and the stanless plates and threaded rod and tubing.

I need the batteries anyway. 1 for my Thing and 2 for my Camper. so if it don't work I just PUT those batteries where I need them anyway. IF IT DOES work it will be worth buying 3 more.

SO its really a zero lose situation for me and a fun experiment. Just no time :-(

I say what the hell try it. I think the reason most people meet with failure is

#1 powering it from the car alternator. Alternators are powered by your engine and therefore are NOT very efficient. any "watts" you gain from the HHO your LOST and then some generating the watts to make the HHO from your engine.

#2 not making ENOUGH HHO. people underestimate just how MUCH your going to need to have any measurable effect. Here is the way I see it. If your at IDLE and you turn the machine on. if your engine speed does not INCREASE on injection of the HHO your likely not making enough gas.

[Frank Lee]

I think the reason most people meet with failure is

they're clueless.

[tjts1]

HHO is BS. End of story.