Pure Oxygen Injection

[AnArKey]

I'm pondering just adding pure oxygen injection. Get a O2 cylinder, some high pressure line, a solenoid, and a jet. O2 should be MUCH cheaper than N20, considering it's used alot in gas welding. I have been trying to figure out why anyone uses N20 when there is O2. O2 obviously is pure oxygen, where N20 is 1/3 oxygen. So, you would only have to use 1/3 as much to get the same HP shot. All regular air is is 79% N2, and 21% O2, so I fail to see how using N20 or 02 makes any difference in the final composistion of the air in the combustion chamber, just that you need to use O2 at a much lower total rate. Consider air is 21% oxygen, N20 is 36% oxygen. That's about a 70% higher concentration of oxygen. In theory, if your car was sucking up PURE N20, it should be capable of making 70% more power than air. Now, to compare, 02 is well, 100%. Using a spreadsheet I compared the final oxygen concentration, using a % for air, N20, and O2. I show O2 as being 526% as effective as N20 at increasing final oxygen concentration. So, you need to use only about 1/5th as much O2 as you would N20 to get the same HP boost. Considering it's probably less to refill a O2 cylinder at a welding store than a N20 bottle at the race store, it sounds like it could be MUCH cheaper in the long run, and each bottle will go 5x as far. Unless I'm totally missing something.

So why is N20 so popular, and nobody uses O2? Is is the fact that O2 is reactive at the moment of injection, but N20 doesn't break apart into N2 and O until 576C (combustion begins)? Does the extra oxygen make pre ignition happen faster/easier? That may be it, but I wonder if the use of water/methanol injection would counteract that anyway.

SNIP

Ah....I discovered something. O2 is stored as a highly compressed gas, at about 2000psi. N20 is compressed until it's a liquid, so a lot more mass of N20 can fit in a bottle than O2. Best I can figure, about 5x mass of N20 fits in a cylinder as O2. So in the end, a tank will last about the same for the same HP shot. Darn.

 

[TurboBuickSix]

If I recall correctly, I think the main reason it is not used is it would cause a catastrophic event if it were attempted,but I could be mistaken.The reason nitrous is used instead is the lower (acceptable)oxygen amount???

 

[WFO]

hey fwiw,you can liquify o2 also.the first f/a-18a's i worked on had "lox bottles"(liquified oxygen)for the pilots to breathe.

had to throw one off the boat one time cuz it had fractured internally and was getting all frosty.that meant it was about to explode .

what you need is an "obogs" (on board oxygen generating system)like the newer f/a-18c's had.then your bottle would never run out.

later,sean

 

[AnArKey]

Originally posted by TurboBuickSix
If I recall correctly, I think the main reason it is not used is it would cause a catastrophic event if it were attempted,but I could be mistaken.The reason nitrous is used instead is the lower (acceptable)oxygen amount???

I addressed these concerns, as far as I can understand them. Obviously you don't use the same mass flow rate of O2 as N20. You use a 1/5th as much, and should get the same result. Why not?

I just called a local welding store. This will be FAR cheaper than N20. Since they do not charge even close to equal amounts, a bigger tank gets better value.

Best I can tell, NOS and all the other nitrous companies use standard gas cylinders. A 20CF cylinder is basically a 5lb NOS bottle. A 40CF is a 10lber, and a 80CF is the 20lber.

A full 20CF oxygen cylinder will provide a 50shot for about 75 seconds. Compare that to the same size 5lb NOS bottle, which will only last half as long at the same HP shot. $10.25 for the oxygen bottle refill, and about $20 for the NOS bottle. Half the cost, twice the life, already 4x cheaper.

Once we step up to a big tank, the 80CF, or the size of a 20lb nitrous bottle, we REALLY see the advantage. To refill the NOS bottle will cost you about $80-$100. To refill the oxygen cylinder will be $14. Of course, as before, the oxygen will go about twice as far. So it's 10-15x cheaper to run oxygen than nitrous in this manner.

Kick ass huh?

It should be noted you will need a regulator to run O2. Since it isn't a liquid under pressure but is still a gas, the pressure in the tank will be constantly dropping from 2200psi down to 0psi (empty). So the best approach I can think of, is use a regulator to drop the pressure down to say 10-20psi, and then use a orifice at the point of injection that limits the CFM of O2 to what you want to use.

 

[cool 84]

The nitrogen is needed as a buffer. Pure oxygen burns way too hot and will melt things very quickly, even in small doses.

Plus nitrous is non-flammable. And as far as I know there is no sulfur added to oxygen so if there's a leak you'll never know it until it's too late.

 

[AnArKey]

As a buffer? Once again, that theory doesn't make sense, so long as you use a much smaller amount of O2 as N20. Air is just nitrogen and oxygen. Nitrous oxide, once combustion is taking place, is just nitrogen and oxygen.

Look at it this way:

Air is 21% oxygen.
N20 is 36% oxygen.
O2 is 100% oxygen.

Engine is sucking in:

90% air
10% N20

(21%*90%)+(36%*10%)=22.5%

The end result will be 22.5% oxygen content, compared to 21% if it was plain air. That's about a 7.14% increase in horsepower potential.

Now try it this way:

98% air
2% O2

(21%*98%)+(100%*2%)=22.58%

The end result will be 22.58% oxygen. That's about a 7.52% increase in horsepower potential.

The composistion of gases in the combustion chamber prior to ignition are practically idential, using 10% N20 or 2% O2.

The only difference I can figure is you won't get any charge air cooling from O2 (it's already a gas) where with N20 you do (it boils as it's injected). I haven't found the math on it yet, but you also won't get the cooling from the process of 2N20->2N2 + O2. I doubt either of these processes remove a significant amount of heat, especially compared to methanol/water injection, which should always be used in conjunction with the proposed O2 injection.

As for leaks, let's not go there. Same discussion as propane. Except propane can ignite, oxygen still needs a fuel, it just accelerates combustion. You could be in a room with 50% oxygen and light a match. The room won't blow up, but the match will burn up VERY fast. If you had 10% propane, BOOM.

Point is, leaks are practially a non issue. These cylinders are very reliable and used by thousands of gas welders.

 

[nisnutz]

Pure oxygen is very flammable worse yet you dont even need a flame to set it off. If any kind of grease or oil comes in contact with it your in deep ****, stay away from it.

 

[AnArKey]

Gasoline is very flammable. You shouldn't use it. Put water in your gas tank.

You might as well have said..."oxygen is bad....you shouldn't use oxygen, oxygen is bad.....MMMM K?"

Oxygen is NOT flammable. Why do so many people never figure out there are TWO elements to combustion, FUEL (which is flammable) and oxygen. If oxygen was flammable, you would set the planet on fire lighting a smoke.

You may recall Apollo 1, where they sat in 100% oxygen for hours. Nothing spontaneasoly ignited. It took a short circuit, and a glowing hot section of exposed wire touching a piece of fabric (which was the fuel), to create a problem. At that point, yeah things went straight to hell in seconds.

I said adding a very small amount to the engine, probably before the turbo. It will mix instantly. You are just converting your intake air from 21% oxygen to 22-24% oxygen. In the end, this is exactly what N20 does.

Tell me why it's different. If I hear one more "it's bad because I say so" I'm gonna go nuts.

Treat a cylinder like a baby? So a 20lb piece of cromemoly steel is as delicate as glass then? If a cylinder pressurized to 2200psi ruptures, it doesn't matter if it's nitrous or oxygen, you are screwed if you are close. Funny I haven't heard tons of stories of people getting blown apart by their NOS bottles, even though there are 10s of thousands of kits out there. Could be because compressed gas cylinders are designed well, and don't rupture or leak easily.

 

[nisnutz]

For a guy that seems to wanna come across as somewhat intelligent yur an idiot. Pure oxygen is extremely flammable.Check before u speak.

 

[nisnutz]

For a guy that seems to wanna come across as somewhat intelligent yur an idiot. Pure oxygen is extremely flammable.Check before u speak.

 

[nisnutz]

Oh and by the way I Work around 99.9% 02 all day and have seen what happened to a guy that tried to use pure 02 to pressure check a hydraulic line. KABOOM

 

[cool 84]

The risks of oxygen are greater than propane. You can smell a propane leak easily. Oxygen is more easily ignited than propane, doesn't always take a spark to ignite it, and you can't smell it. About needing a fuel, I'm not sure about that but I've seen the regulator blow off of an oxygen tank and there was a huge flame blowing out of the broken line. I'm not sure what the fuel was in that case. Are you forgetting in your formula the nitrogen that's already in the intake air along with what's in the nitrous?

 

[slimtastic]

basicly whats going on is that when you use pure oxygen for a flame, very little fuel is needed hence the neutral flame on a torch...dont do it.

 

[sstock]

"Pure oxygen is very flammable worse yet you dont even need a flame to set it off. If any kind of grease or oil comes in contact with it your in deep ****, stay away from it."

This is a good thread but I'm sorry you are wrong. Oxygen is 'NON Flammable" gas. Oxygen is an oxidizer meaning it adds no fuel to the fire so to speak, however will allow things to burn that otherwise would not burn in an atmoshere of 21%.

Example: Our Nomex hoods that we use in the fire service will not burn at 21% oxygen however in an oxygen enriched atmosphere of 30% nomex will burn and burn very fast.
So to recap, Oxygen is not flamable but I fear with flammable liquids under compression and combustion could cause an extremely hot cylinder and cause melt down or worse yet a small explosion in short term. Just my .02
Remember the liquid O2 explosions of the early Mercury space missions?

Later
Steve

 

[AnArKey]

Originally posted by cool 84
Are you forgetting in your formula the nitrogen that's already in the intake air along with what's in the nitrous?

No, I included that. I DID however fail to account for variences of density, which I have corrected for on my excel sheet I'm doing on this. I don't want to write them all out, but it didn't change the crux of the argument, just the ratio of O2 to N20 to get the same final result. It wasn't AS good, but still pretty good.

nisnutz, now that we are name calling, I think it's pretty easy to see who the idiot is. Flammable oxygen is not. That's not the word for it. Yes it can make the potential for danger with flames much higher, but O2 isn't is NOT classified as flammable. Here look at this O2 MSDS:

http://www.weldingsupply.net/oxygen1.htm

Special Fire Fighting Proc: OXYGEN IS NONFLAMMABLE, BUT SUPPORTS AND
VIGOROUSLY ACCELERATES COMBUSTION OF FLAMMABLES. TO FIGHT FIRES, SHUT OFF
SOURCES OF OXYGEN AND FIGHT FIRE.

About liquid O2, shouldn't even be in this discussion. That's a whole other level to deal with and I'd never suggest it.

It still seems promising, but I think there migth be issues with regulation more than anything. Needs to be very accurate and a flow rate never used before. Neither welding nor breathing devices have ever needed to use up O2 at the rate the engine would need to. Apparently, regulators are also not very reliable, from what I have heard. I'd need a almost fail proof regulator, as a big leak would be a disaster.

 

[WFO]

Originally posted by nisnutz
For a guy that seems to wanna come across as somewhat intelligent yur an idiot. Pure oxygen is extremely flammable.Check before u speak.

sorry 'bout your luck numbnutz,but oxygen is an inert gas.

i'm a certified welder and i put out fires all the time with straight oxygen.

 

[WFO]

Originally posted by AnArKey
About liquid O2, shouldn't even be in this discussion. That's a whole other level to deal with and I'd never suggest it.

rumor has it i was being facetious about that one...

'course rumor has it i'll drink jameson's for breakfast...

 

[wistleofdeath]

O2 is not flammible. it aids in in combustion they use it to cut steel I would not like to put that in my iron cumbustion chamber

 

[AnArKey]

OK, this one has been going on over at eng-tips.com, and finally I got a answer about WHY it's a bad idea.

Nitrous comes open, releasing oxygen after combusiton has begun. It does not effect the compression cycle, as if anything it reduces the oxygen % in the chamber until it breaks open.

O2 injection would net a oxygen enriched air charge all through the compression phase. Higher oxygen content, even 1-2% like I am suggesting, is enough to drastically increase the ignitability of the fuel/air charge. In other works, it acts like a detonation catalyst, and nitrous doesn't, at least not directly.

So, there you have it.....bad idea. But at least I know WHY. I didn't want to drop it from a bunch of "oxygen is Bad....MMMMK" comments. Take a peek at the hydrogen peroxide thread, that's looking very promising.

 

[TurboBuickSix]

I was gonna say what you said, but did'nt want to sound like a know-it-all, mmmmk?