DIY Hydrogen additive...?

[teoman]

Rusty, did you measure any gains?

How many amps was your cell consuming?

[RustyLugNut]

Originally Posted by hayden55

It sounds like a great idea. So you start with 35% efficiency engine, then a 65% efficient alternator, and then you have a 30% efficient electric fuel cell. Sounds like 6.825% efficiency being added back to the engine... but i forgot to add in the free energy so with that added in its more like 120% efficiency.

Did you read my post? Did you understand it? Can you refute its basis?

[RustyLugNut]

Originally Posted by RedDevil

In some unique cases you can get lightly better economy by introducing water mist, but not if you have to split the hydrogen from the oxygen to merge them later on again.

Unicorn corral, you're needed.

Was it you who argued against my position on another thread? I asked you to bring it to someone who had the education and knowledge to understand my post. He replied that it is plausible. Read my post. There is nothing untoward in its basis. If you don't understand it, find someone who does.

[RustyLugNut]

Originally Posted by teoman

Rusty, did you measure any gains?

How many amps was your cell consuming?

On the gasoline engines, both carb and fuel injected, an average of only 5% gain was found (2-10% range ) playing only with timing and producing a set power output ( about 20 hp if I recall correctly ). But these were the vehicles that responded to the addition of HHO. Some vehicles saw zero gains. One had a -2% loss. I think you can see what I am going to say next. There are a bunch of parameters that contribute to HHO even being measurably effective, and this is at part load. It must be noted that the dyno we were using was not set up for low power loads and it's 0.4 hp gradients meant at 20 hp testing 2% was its minimum detectable change. We had hoped to get into an EPA approved lab or the local university dyno lab but time and cost meant we had to use time bought on a local hot rod shop which was set up for hundreds of horsepower measurement. Simple A-B-A-B testing was used to verify findings.

The cell stack had 4 cells in series pulling 15 amperes from the vehicle alternator and externally heated with water recirculating at 80 degrees C. A current limiter with a feedback circuit was used. The production of hydrogen is directly measurable by the amperes. One Coulomb per second is an amp, so just multiply that by 60 to get your moles per second of hydrogen. Each cell is cylindrical and was run at 1 atm.

This test was done a couple decades ago to see if these HHO devices held any merit. What we realized was, . . . it depends.

It depends on intake air temperature, combustion mixture turbulence, the presence of hot EGR and the makeup of the combustion chamber material ( iron heads were preferential to aluminum ) .

A test on a 1990 Daihatsu with a 993 cc gasoline engine was done as it's fuel and ignition timing were easily manipulated. It was California compliant with EGR and provisions for a hot air intake from earlier models. Even with it's aluminum head it gained just under 50% increase in fuel efficiency running on lean burn at an AFR of 28:1 which was the limit of our wide band oxygen sensor (WBOs). The 50% gain is from the lean burn, of course. However, the lazy hemispherical combustion chamber of this engine allowed only about 20:1 AFR before erratic combustion started rearing it's head ( COV>5% using pressure sensors under the spark plug and audio readings externally ). With the addition of HHO we could peg the WBOs at 28:1. HHO allowed the extended lean burn.

Now people are going to ask, why didn't we pursue a marketable unit? Simply, it didn't make economical sense for consumer vehicles. And emissions were impossible at that time without the use of the now available lean NOx traps. And with tightened current emissions, the time period of running lean allows the catalytic converter to cool down thus, when the engine switches to stoichiometric running, the cat is too cool to be effective and elevated emissions result. This is pretty much why all lean burn schemes have disappeared from the North American and European markets.

[RustyLugNut]

As a side note, we revisited the idea of HHO in 2008 as I was part of an Xprize entry.

We modified a 2.4 L Mercedes diesel ( iron head ) by machining the glow plug holes to accept Ford long reach spark plugs and running the engine on syn-gas from diesel using a POx technique. HHO was added in a very small amount to smooth out the combustion. All the gasses were added in the intake and thus, the engine had to run very lean or destructive knock would occur at 21:1 compression ratio. The calculated AFR was well north of 30:1 . This is in corroboration with the findings of pfgPro on his turbo Talon. This engine was hoped to get our 190 D Mercedes near 100 mpg.

[teoman]

Thank you for the detailed answer.

As far as I understand it is not really for the average joe. You would need a lean burn enabled car to begin with, and then have the ability to chane the advance parameter of it.

[RustyLugNut]

Originally Posted by teoman

Thank you for the detailed answer.

As far as I understand it is not really for the average joe. You would need a lean burn enabled car to begin with, and then have the ability to chane the advance parameter of it.

I have always wanted to construct a hybrid gasoline/electric drive train where the engine is a slow turning, over sized, lean burning only design. Most of the motivation to putter along at low speeds and also to accelerate would be provided by an electric drive. The engine would be a narrow speed ranged engine tuned for maximum efficiency at your normal cruising speed with final drive ratios tuned so the engine operated between 1600-1800 rpm. Heat exchangers to warm the incoming air as well as metered EGR allow us to run sub-critically of detonation. A POx ( partial oxidation process ) chamber would feed the intake with CO and H2 to provide the high octane syn-fuel.

Hold it! You are saying that syn-gas already had hydrogen? Why do you need the HHO generator?

Good question.

Several years ago, a discussion on the Physics.org forums hooked me up with a graduate student in India who was interested in making an electrolysis unit to provide OXYGEN to his ozone generator. He had high hopes of producing an effective unit to deodorizer and disinfect. Interestingly, he found a measurable amount of ozone already in the oxygen stream coming from the electrolyzer. The amount increased to several hundred parts per million (ppm) if impure tap water was used in the electrolyte. SwRI ( Southwest Research Institute ) did a paper a while back where ozone concentrations as low as 40 ppm measurably accelerated combustion in a natural gas mixture. Several hundred ppm would be significant.

I feel the majority of the combustion effects of these so called HHO generators comes from the oxygen stream and the accidental inclusion of ozone. Not to discount what hydrogen can and does do in railroading the production of reactive species, but you might see greater benefits if we sought to maximize the production/addition of ozone.

But at this point, Life and the Wife limit my time to experiment on this topic. Maybe someone out there might be inspired to do so.

[teoman]

Interesting...

My 2 cents that just popped in to my mind. I am told not to store my diving equipment in the same room as electric motors run (brushed type is implied i believe) because the arc generates ozone which deteriorates the rubber.

So intake manifold sucking over the alternator?

[RedDevil]

Back in the days this subject came up a dozen of times, in no small manner spurred on by RustyLugNut, I tried to find any scientific backing for the idea that tiny amounts of hydrogen would indeed have a significant effect on engine efficiency on regular car engines.
But I could find none.

It is clear that a relatively large amount of hydrogen does have an effect, as it is consumed as a fuel and affects the burn speed and pinging resistance of the air/fuel mixture.
So that is a thing.
But it requires an additional supply of hydrogen. Electrolysis could never generate enough, due to its inefficiency, and so it would never offset the gains.

If a very low amount of hydrogen would have the same effect then the inefficiency of electrolysis would be less of a problem.
There are studies that show the effect exists even with trace amounts; like the one that IIRC used a purpose built block with a 30-1 compression rate and octane fuel on severe lean burn (not unlike Rusty's X-prize setup).
Under those conditions even seed values of hydrogen do have an effect.
But not in anything resembling a regular car engine using ordinary fuel.

Then the addition of water mist can give a few % improvement in the right conditions, I assume by reducing pumping loss and by adding volume to the exhaust gas, which is especially useful when the head is hot enough anyway.

Even if you do find efficiency gains from using a 'HHO' bubbler that may have more to do with the water that comes with the bubbles.

[19bonestock88]

So one could imply that installing a bubbler alone(no HHO) could help efficiency...