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-   -   Need some help with my math, how much HHO needed? (http://www.fuelly.com/forums/f32/need-some-help-with-my-math-how-much-hho-needed-9808.html)

JohnNeiferd 08-24-2008 01:04 PM

Need some help with my math, how much HHO needed?
 
First off, I know its not practical at all to run an engine on solely HHO made with a common hydrogen generator. But that?s besides the point, I need some help with the math here.


Can someone help me figure out what I did wrong with these calculations and what steps I need to add in?

A Geo Metro 1.0L engine running at 3200rpms (estimated at 65MPH) and at 60% throttle would require 67.8042CFM (cubic feet per minute) of the air fuel ratio.

(1000cc X 3200rpms) / 2.54 / 2.54 / 2.54 / 12 / 12 /12 = 113.0069cfm X 60% = 67.8042

We?ll assume that we are running a stoichiometric ratio at 14.7:1. That means there is a total of 15.7 parts (14.7 + 1 = 15.7). We?d need 63.4854 of air and 4.3187CFM of fuel.

(67.8042 / 15.7) X 14.7 = 63.4854CFM of air.
(67.8042 / 15.7) X 1 = 4.3187CFM of fuel.

An important key to remember is that Hydrogen Generators split the water, H2O. This means it not only generates hydrogen but also oxygen. There are 2 hydrogen molecules and 1 oxygen molecule, which gives us a total of 3 molecules. (2 + 1 = 3). So, in order to get 4.3187CFM of fuel (Hydrogen), we?ll need more than 4.3187CFM of HHO because part of it is oxygen. So we?d need 6.4781cfm of HHO to create 4.3187cfm of Hydrogen.

(4.3187cfm of HHO / 2) X 3 = 6.4781

With 6.4781cfm of HHO, we?d have?

(6.4781 / 3) X 2 = 4.3187cfm of Hydrogen
(6.4781 / 3) X 1 = 2.1594cfm of Oxygen

Therefore, in order for a 1.0L engine to run on HHO we?d need to inject 6.4761CFM of HHO and the engine would have to suck in 61.3260CFM of air.

However, when talking about engines and hydrogen generators, liters are more commonly used them CFM. So, we have to inject 183.3827 liters per minute of HHO to run an engine on pure HHO.

Using www.ask.com 6.4761CFM is 183.3827 liters per minute.
Using www.ask.com 61.3260CFM is 1736.5590 liters per minute.


I checked my math and it seems to work out, but I must be missing something. Because if I was trying to figure out how much gasoline an engine needed, wouldn?t I use the same method? But 183.3827 liters (48.4446 gallons) of fuel per minute is definitely not correct.

Can someone help me figure out what I did wrong with these calculations and what steps I need to add in?

ashoda 08-24-2008 06:36 PM

The volume of gas you produce for a gallon of gas is very different then putting HHO as a gas into your intake. As the gas travels through the intake it changes from a liquid to a gas state, while your HHO is already in a gaseous state.
I am interested in the method you are using to produce your HHO gas?

nowhhs 08-24-2008 06:53 PM

I'll try to find some of the obvious mistakes. First, the engine only sucks in air/fuel during the intake stroke, so your 3200 rpm = 1600 intake strokes/min. Change the 3200 to 1600. Next, throttle position has very very little effect on the amount of air/fuel being sucked in, 3200rpm uses approximately the same amount of air/fuel whether at 20% throttle or 100% throttle, so take out that calculation. Next, 14.7:1 ratio is by weight, not volume, which is what you're doing. So to find the amount of fuel you're using, you first have to find the weight of the air your engine is pumping. That makes the rest of your calculations moot, so when you get to this point, re-post and I'll try to "help" more. Good luck.

JohnNeiferd 08-26-2008 04:32 PM

I haven't been able to construct a HHO generator that puts out resonable amounts of HHO within taking in too many amps. I made one large one that takes around 30 amps, might work good vehilces with large alternators, but not small cars. I've just been using the classic steel plates, baking soda, and water. No measurements or anything, I just mix some baking soda, water, and run some electricity through it.

nowhhs, as for the calculations, I'll give them another try by converting it to weight. Not quite sure how to do that for sure, especially in dealing with HHO in its gaseous state. ill see what i can do though

nowhhs 08-27-2008 07:37 AM

Speaking for myself, thats why I don't believe in HHO, you can't make enough of it to make any difference at all. If you do, using tons of electrical power, the current draw at the alternator drags down your engine more than the HHO benefits you. You can't win. I don't want to get into an argument or "discussion" with anyone about it, thats just my 2 cents. YMMV

JohnNeiferd 08-27-2008 08:48 AM

I know what you mean, I don't believe in HHO either. However, if anyone was skilled enough to create a small version of a heat exchanger, where the exhaust heat boiled some water and the steam turned a turbine attached to an alternator, then you'd be able to turn that wasted exhaust heat into additional fuel, HHO.

I was just trying to do the math to see how much HHO it would be necessary to produce if someone did make this type of system. I know some automakers are working on a "turbine alternator" where the flow of exhaust gases turns the alternator, but I figured one that uses heat would be a little more efficient since it wouldn't generate any additional backpressure.

dkjones96 08-27-2008 09:03 AM

Yeah, your throttle calculations are a bit off. There is a huge difference in manifold vacuum from idle to 50% but after 50% there isn't much difference to 100% but that depends entirely on your rpm. On the dyno, my car will make 75ftlbs at 2000 rpm at 25% throttle and 100 at 50% and 115 at 100% but 25% drops off to almost no power(35 ft lbs) by 3250 when 100% just finished its first peak to 130 ft lbs.

GasSavers_BEEF 08-27-2008 12:07 PM

johnneifred,

that's just water injection though. if you boil water, you get steam not hydrogen and oxygen. when the steam cools down it recondenses.

there have been benefits to water injections especially in turbo engines if for nothing else, to keep the turbo cool

*edit* my bad, I re-read your post and you said to create steam to turn an alternator. sorry man

JohnNeiferd 08-28-2008 11:51 AM

Thanks for the edit BEEF, I was just about to try to re-explain what I meant, but I you've figured it out.

As for my calculations, I'm not sure how soon I'll get to them. I've been talking to Erik about how to lean out my '87 Civic and right now I'm waiting on a vacuum gauge I ordered from Ebay. Once I get the vacuum gauge I can compare reading at WOT (should be zero) and at half-throttle and such, and that should help me figure out how to get my calculations straight.

R.I.D.E. 08-31-2008 05:08 AM

You calculate the total volume of HHO as fuel, when only 12.5% of HHO has any BTU energy. That is the Hydrogen. Oxygen contains no BTUs of energy.

You need to multiply your HHO volume by a factor of 8 to get your calculated fuel volume up to the level you have stated.

If you want to directly compare the liquid volume of Hydrogen to Gasoline you need to reduce your Hydrogen to a liquid volume which is about 1/860th of its gaseous volume.

Even then its mass is much less than Gasoline, not sure of the weight ratio, but I would bet Gasoline is 10 times heavier for the same liquid volume.

regards
gary


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