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Hydrogen generator, a failure as you guys said
2

Hydrogen generator, a failure as you guys said

Hydrogen generator, a failure as you guys said

(OP)
OK on board hydrogen generator, from water, fully tested and a glowing failure. Advertised volume was 1 liter/minute, tested at 17 and 15 amp draw it would only produce 1 liter every 2 minutes 15 seconds, 1/2 the spec volume. Anything beyond would boil water in generator. 17-18 amps for several muinutes seemed to be the peak before boiling. I tested it anyway on a 1996 Saturn 1.9L vin"8" engine using a scangaugeII reading serial data, the unit is very accurate and calculates instant MPG, average MPG, load, rpm, fuel used, distance ect. I have used it for several months now and tracked it's accuracy, which I was impressed with.
Test data 20.4 miles 2200rpm about 60mph, mostly flat expressway, low traffic, acceleration not above 80% up to cruise speed Normal engine 43.3mpg, .5 gal used
             Hydrogen on   42.6mpg, .5gal used 15 amp draw
Oxygen sensor was disconnected and the mileage never changed.No difference was seen on the fuel trim numbers or even the oxygen sensor graph, at idle. I feel the volume was so low that it had no effect at all. We bubbled the hydrogen into water and ignited it as it came to the surface, all we observed was a very small "pop", this amount of energy would have almost no effect on a full breathing engine at 2000rpm.
So as most of you said, save your money, I opted for a full refund as advertised.
Gary Para contact me for any more information gpara@mis.net
SAE, ASE PMTA, BS. IN&T L-1 certification

RE: Hydrogen generator, a failure as you guys said

Let us know how long it takes to get your refund.  I have heard that it can be forever on these kind of things.  I believe that even if you could break down water fast enough to make a difference, the alternator load would consume more energy than the H2 would yield.  Everything I have ever read says that it takes more energy to electrolyze water than the energy it yields.

RE: Hydrogen generator, a failure as you guys said

I don't want to defend the indefensible, but you are missing the point. The hydrogen is not being used solely as a fuel, the benefits of hydrogen as a combustion initiator are well known in the literature. The idea is that the hydrogen improves the combustion process for the gasoline as well.

Nowm, that may not work, or it may absorb more energy to amke the hydrogen than the compensating improvement gives, but it is not a totally stupid idea.

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: Hydrogen generator, a failure as you guys said

Out of curiosity, was this the hydrogen boost version?

RE: Hydrogen generator, a failure as you guys said

2
(OP)
The generator was supposed to increase fuel economy 20% min. increase power, keep oil cleaner ect. Looking back thru the communications it was supposed to generate 2 liters/min, not 1, perhaps at that level it could have effected the economy but as it stands now, you saw the test results. The company did give me a return address, from Florida where it was sent after I submited the test data to them. It is going back today and will let you know when the refund comes. Perhaps the states attorney would be interested in the false statements made by this guy. Web site is out of Canada, but shipped from Florida. I wounder if he is trying to hide being listed thru another country????? It was worth the effort to at least see if H-0 readded to the combustion processe did anything for the IC engine at the low level.
Gary

RE: Hydrogen generator, a failure as you guys said

A 1.9L, 4-cycle engine at 2200 rpm consumes 2090 L/min of air-fuel mix. So, even 2 L/min of H2 is only 0.01% of the total. Adding the 1 L/min of O2 also produced would help (or is that done, already?).  But, more energy input than output.  Perhaps, solar cells on car roofs for the electrical input.

RE: Hydrogen generator, a failure as you guys said

I'm telling you guys... a nuclear reactor is the answer.  Now aside from the problems with every Tom, Dick and Muhammad having access to nuclear materials, it would mean never having to fill up for 10, 20, or 30 years?  

I'd support that, just get a fusion reactor together when my first fuel cell runs out in 30 years.  :D

RE: Hydrogen generator, a failure as you guys said

GregLocock, is it possible that such a small hydrogen mass could change combustion in such a dramatic matter?

There is a company stating an "ultra-lean burn" spark ignited engine with hydrogen boosting.

Thank you.

RE: Hydrogen generator, a failure as you guys said

Look for papers by Dr Harry Watson. Yes, it doesn't take much hydrogen to modify the combustion process.

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: Hydrogen generator, a failure as you guys said

(OP)
Just for your information, refund was within 5 days of return of generator.

GP

RE: Hydrogen generator, a failure as you guys said

gpara

the claim of 20% improvement in fuel consumption is still conservative. The one from this side of the world claims that there will be 50% improvement in fuel consumption. I checked on the demo vehicle but as expected there was no increase in torque or power if compared to the original car without any electrolizer installed. how on earth can anyone expect a 50% improvement?

There is one FISITA paper on how a japanese researcher improved a CNG DI engine using hydrogen premixed with the CNG. This is ok because the researcher was looking for way to improve the misfire problem when runned at ultra lean burn mode.

Claiming or boasting that hydrogen can be generated onboard a vehicle using water is just plain stupid. In the first place, if we invest 2J to get 1J of heating value from hydrogen, how can we expect 50% or even 20% fuel consumption improvement? electrolysis is not 100% efficient, generating electricity from alternator is also not efficient.

RE: Hydrogen generator, a failure as you guys said

Azmio,
Re "In the first place, if we invest 2J to get 1J of heating value from hydrogen, how can we expect 50% or even 20% fuel consumption improvement? electrolysis is not 100% efficient, generating electricity from alternator is also not efficient."

It's a lot worse than that. An auto engine is only about 33% efficient in converting heat into mechanical energy, and I suspect an alternator is ~45% efficient at converting mechanical into DC electrical -- it makes AC, then half is absorbed by large diodes (waste heat) in making the DC, so a cooling fan is required. So, from 2 J electricity, get 1 Joule of heat which only produces 1/3 J mechanical --> 0.15 Joule electricity = -92.5% loss.

RE: Hydrogen generator, a failure as you guys said

... An on-board ammonia generator using H from water and N from the air (don't ask me how it would work) would make a lot of sense.

RE: Hydrogen generator, a failure as you guys said

kenvlach

you're right, with all this inefficiency we have not even discussed about the temporary storage and transporing the hydrogen from one location to another. With such a lightweight molecules, hydrogen can easily leaks out. This will further go against hydrogen and the device that gpara bought.

somptingguy.

i read about that as well. If i am not mistaken, the chemical reaction involving ammonia will still require activation energy to get hydrogen. Where will this come from? nothing comes for free in this world.

I somehow still wonder, is the hydrogen economy real or it's just something to win vote during election?

RE: Hydrogen generator, a failure as you guys said

Azimo, you may have missed the point.  On-board ammonia generation would eliminate the need to buy bottles of AdBlue (or equivalent) for SCR systems.  Agreed it'll require some energy input, but it might be less than that required to manufacture and distribute urea.

RE: Hydrogen generator, a failure as you guys said

I went to a web link from the above link for Hydrogen generators a 600 cc/min generator consumes <1200 watts. Here is what it costs.  I've included other fuels too. The reason methane is cheap is because there are no taxes on it, similar for propane.  Take taxes from the others and gasoline and disel are neck and neck the cheapest on an energy basis.  Oh, and for all diesel users, you should get about 15% better milage because diesel has 15% more energy than gasoline........

    HYDROGEN            
    1100    watts    From Brochure
    600    cc/min    From Brochure
    36000    cc/hr    
    1.27    ft^3/hr    
    274    BTU/CF    
    347.98    BTU/hr    
    102    watts    
    $0.10     $/KW-HR    Electricity Price
    $0.11         
    $316.11     $/MMBTU    For H2
GASOLINE            
    125000    BTU/Gallon    
    $2.50     $/gallon    
    $20.00     $/MMBTU    
Methane            
    56000    BTU/Gallon    
    $1.10     $/gallon    
    $19.64     $/MMBTU    
Propane            
    100000    BTU/Gallon    
    $2.00     $/gallon    
    $20.00     $/MMBTU    
Disiel            
    140000    BTU/Gallon    
    $2.70     $/gallon    
    $19.29     $/MMBTU    
Electricity            
    1    MMBTU    
    293    KW-hr    
    $0.10     $/KW-hr    
    $29.30     $/MMBTU    

RE: Hydrogen generator, a failure as you guys said

A few more thoughts regarding the hydrogen generator:

At higher temperatures electrolysis can actually reach an efficiency above 100% (if you don't count the waste heat as energy - which you do have anyway).
http://en.wikipedia.org/wiki/High-temperature_electrolysis

Also, when you lift the throttle and increase the load on the alternator, you can use wasted braking energy to produce hydrogen.

So, one could possibly and mainly use waste energy to generate that extra hydrogen.

Adding hydrogen can improve the combustion process:
Since hydrogen can accelerate the combustion process this could be an advantage at low throttle settings when burning speed is lower and efficiency suffers. (The faster the combustion, the higher the efficiency).
Also, as hydrogen does ignite at leaner settings than gasoline does, this concept could be an additional advantage at low throttle settings and high pumping losses.

Obviously, as has been mentioned, additional NOx would need to be reduced (for instance, with a NOx-catalyzer).

However, if you consider the complexity this entire system would add, there might be simpler ways to increase efficiency on a gasoline or diesel engine.

RE: Hydrogen generator, a failure as you guys said

globi5

"Adding hydrogen can improve the combustion process:
Since hydrogen can accelerate the combustion process this could be an advantage at low throttle settings when burning speed is lower and efficiency suffers. (The faster the combustion, the higher the efficiency)."

Is hydrogen really introduced to accelerate the process? It would seem the octane rating is to slow the burn rate..or have I had a senior moment??

Cheers

I don't know anything but the people that do.

RE: Hydrogen generator, a failure as you guys said

At low throttle settings you don't need all the octane that is required at WOT (but you've got it in the tank anyway).  Something like H2 to accelerate the burn at low BMEP could indeed enhance efficiency.  Going leaner instead of throttling can also lead to improved efficiency.

RE: Hydrogen generator, a failure as you guys said

thundair,

hemi is correct.

Saab made a variable compression ratio engine with a maximum compression ratio of 14 in order to take full advantage of the gasoline at low throttle settings:
http://www.saabnet.com/tsn/press/000318.html

RE: Hydrogen generator, a failure as you guys said

And of course hydrogen has a higher flame speed than pretty much anything. (Hydrogen is the lightest molecule and steam is also lighter than CO2).

RE: Hydrogen generator, a failure as you guys said

(OP)
All of this is mute because it made NO difference when added to a fuel injected engine.The extra Hydrogen did nothing to enhance the combustion or mileage without modifying the operating system. All these claims are for standard engines with extra hydrogen added.
Gary

RE: Hydrogen generator, a failure as you guys said

I don't doubt your test results and the usefulness of these systems sold online.

But I don't think it is impossible to gain anything out of it per se.
As you mentioned, the amount of hydrogen added to the combustion will need to be significantly higher.
And fuel management and throttle control would definitely need to be adapted.

However, it might make more sense to use all that extra electric power to power an electric motor connected to the drive or a supercharger and gain efficiency this way.

RE: Hydrogen generator, a failure as you guys said

I just wonna start new thread, and fortunately I spot this one. It exactly cover what I have in mind.

I think most people have little understanding when exactly adding extra hydrogen to in regular fuel mixture (gasoline or diesel) will have any impact on general fuel economy.

The only time when you can expect significant improvement in fuel economy with added hydrogen is when the engine is in extreme operational condition. That specially apply when the engine is in high RPM. That mean very short time to perform complete combustion.  
I do not think that you will see much of a different in highway driving. You probably will see much bigger difference in city driving. Starting the car from total stop  required the engine to go to high RPM. This where combustion become less deficient . And this is the point where extra hydrogen may help.
I so on one of the web sides that sell the hydrogen buster that the old SAAB with turbo have the best improvement in fuel economy. That might have some sense specially in the older cars.  

Now to the point that I really wonna talk about.

I read some info about Wankel rotary engine.
The engine have remarkable power to wight ratio.
Mazda by the way did pretty good job on that engine.
I found all that advantages of: low weight, high power , simplicity....
The biggest disadvantage is that this engine use a lot of fuel. One of the reason of that it have difficulty to burn all that fuel. Reason for that is, very short period of combustion, and "inconvenient " shape of combustion chamber (very long and narrow as oppose to piston engine).
The result is high fuel usage (basically a lot of hydrocarbon go un burn thru exhaust).
Mazda solve the problem with high emission of hydrocarbons by using "afterburner" with extra fuel from the tank (that make the millage even worst).
Another solution Mazda did (in there experimental car) is just usage of hydrogen instead of gasoline. That solve all the problem (except come from we can get cheap hydrogen).

The question is.
What will be the impact on Wankel rotary engine fuel economy if extra hydrogen generator was used to improve the speed of combustion?
Should the millage improve?
Should the level of un burn hydrocarbons by reduce?
How much of hydrogen we will need to see the difference if any?

   

RE: Hydrogen generator, a failure as you guys said

There are good reasons to start your own thread instead of hijacking some one else's thread.

If you start with the poor thermal efficiency of a rotary, then add some special technology to improve it you can also apply the technology to a piston engine. Youmight close the thermal efficiency gap between rotary and piston but you will not surpass the piston engine.

The three problems with rotary engines and fuel efficiency are:-

Combustion chamber shape. This is somewhat offset by the leading and trailing spark plug arrangement.

Chamber surface area to volume ratio. This is inherent and can't be fixed.

Port timing is fixed and cannot be varied by changing cam or cam timing on the run.

Their advantage is their power density that allows for a smaller motor and as crank speeds are high, the torque is low, so a lighter duty gearbox can be used. This all helps save fuel by reducing chassis weight and maybe reducing friction in the gear box with smaller gears, but at higher speeds.

Regards

eng-tips, by professional engineers for professional engineers
Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips Fora.

RE: Hydrogen generator, a failure as you guys said

As far as thermodynamics goes: Wankel engines and gasoline piston engines both adhere to the Otto-cycle.
http://www.grc.nasa.gov/WWW/K-12/airplane/otto.html

So, speeding up the combustion at low loads will improve combustion in both piston as well as a Wankel engine, because it will adhere closer to the ideal Otto-cycle.

In a Wankel engine it will create bigger gains because the extremely high surface area will cool the gases even more the longer the combustion takes.
Also, one other issue with the Wankel engines is the moving combustion chamber, which seperates the heavier gasoline molecules from the lighter air molecules and enrichens one end of the combustion chamber, which obviously also worsens the slower the combustion. This should indeed be less of an issue with hydrogen.

Keep in mind: The Mazda 787B winning Le Mans 1991 with a naturally aspirated Wankel engine did not have a reduced fuel economy compared to its turbocharged piston driven counterparts even though the Wankel engines are generally not known to be economic. This is related to the fact that economy of Wankel engines suffer particularly at low loads and race cars are hardly driven at low loads.

On the other hand though, pumping losses do not really exist with a Wankel engine, because the rotor doesn't work against any pressure in a crank housing. So reducing the pumping losses by opening the throttle and leaning the mixture will not generate the same benefits with a Wankel engine as with a piston engine.

I wish Mazda would release some data regarding the combination of driving its gasoline/hydrogen RX-8 on mainly gasoline and use hydrogen just to speed up the gasoline combustion particularly at low loads. (Obviously they won't, because this was and is not the goal of their project).

RE: Hydrogen generator, a failure as you guys said

Oh, btw and still off topic. Wankel engines do have variable port timing - probably even before the piston engines applied it commercially.

Even the very first commercially available Wankel engine in the NSU spider already had variable port timing. 2 intake ports and the second port would open after reaching a certain load and/or rpm.

The Renesis engine in the RX-8 actually has 3 intakes ports (3 on each side: 6 per rotor).
And possibly the only engine (including piston engines) currently produced without port(valve)-overlap (and still reaching max power at 8500 rpm).

Obviously the timing of each port is fixed (and not variable) and they also don't have variable exhaust port timing - but still.

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