does nitrous burn?

[arskiracer]

Some guy from a custom engine shop told me that nitrous didn't actually burn, but it expands like crazy when it gets hot. He said the expanding gas is what makes the huge performance gain. Is that true?

[FastCougar]

Technically, he is right ... sort of. Nitrous does not burn ... that is gasoline's job. The idea is the have gasoline act as a catalyst to burn oxygen. Nitrous Oxide is chemically N20 ... 2 nitrogen molecules and 1 oxygen molecule. N20 will break down into it's two components, nitrogen and oxygen. This occurs somewhere around 575 degrees F ... in the combustion chamber. That is why nitrous MUST be offset with fuel. Without the extra fuel, when this chemical break down occurs, the engine would run lean and BAM ... kiss your engine goodbye! However, if you light a match and open a bottle of nitrous, nothing will happen except the match will be blown out.

[arskiracer]

so the fuel burns with the oxygen... what does the nitrogen do?

[exigent]

prolly combines with other stuff when the oxygen bond is broken.


You shop dude is right... n2o wont burn... well... it will burn but not like its propane or natural gas or somthing. It burns like oxygen burns. Remember your fire triangle?



Anyways... nitrous is air in a can basicly. Hes half right... when it turns from a liquid to a gas it expands and COOLS.... this raises the pressure in the manifold and cools the mixture... and the oxygen helps the burn.

[Aries]

Yeah, Nitrous is an Oxidizer.. it's not flammable.

I remember doing a project in science class, where we took an upsidedown test tube full of oxygen, and another one of hydrogen.. we lit a match, and put it in each. It didn't do anything in the oxygen, but there was a small burst of fire in the hydrogen. Then we took a lit match, and blew it out, and tried it again. The match re-lit in the oxygen, and did nothing in the hydrogen.. The oxygen helped the match burn. The nitrous is basically feeding lots of oxygen into the engine.

I dunno if this makes any sense... but what the heck.. I thought I'd just throw in the few bits of education I got in High School.

A question though.. Why don't they just inject pure oxygen into cars? Why add Nitrogen?

[Faboo]

packaging right???........oxygen is a diatomic....right??

i dont know what that has to do with anything...but i'm trying to act like all those years of school did something. good question Aries, i wonder the same thing

[EllenD]

Yes, Oxygen is diatomic, just like Nitrogen, but basically what fastcougar posted is the entire story. There was a discussion about whether nitrous was flammable, and the answer is no, and yes. If you light a match around free N2O nothing will happen, but under pressure in the can it will combust. So don't go throwing cans of it in fire. I've known people that for some reason did that for fun and lost most of their hair and parts of their faces.

Fastcougar I'm impressed...are you a science freak or just a car freak? I have my degree in pre-med and I always feel like such a dork when I talk about things like that. Glad to see someone else knows some stuff too.

[Pinebox]

From what I remember from chemisty, the nitrogen molecules are very cold. So, when the N2O molecules breaks apart in the combustion chamber, the oxygen burns with the fuel, and the nitrogen actually makes it "colder" in the chamber. The combustion with the extra oxygen and fuel makes the extra power, and the nitrogen keeps it "colder" than it would be without it. The way I see it, it's good things from one swtich. :)

[Kinger]

Here is my grand explanation copied directly from the wonderful internet :) Nitrous Oxide is comprised of 36% oxygen as compared to about 21% that is in a normal atmospheric intake charge--that's about 70% more oxygen! More oxygen means more combustion which in turn means more power (assuming that there is sufficient fuel to burn the additional oxygen!)

So if greater oxygen and fuel content in the combustion chamber cause the increase in horsepower, why not just inject oxygen? Well, the engine would produce more power than it could handle and simply blow up! Once the N2O is injected into the chamber and the temperature reaches 572°F (on the power stroke), the molecules breakdown and the the nitrogen and oxygen molecules are separated. The oxygen is immediately burned and the remaining nitrogen helps to dampen the combustion so that the above problem does not occur.

[Nipanther]

Another thing that the Nitrous does is it causes the molecules to speed up by directing the cold to confine the space.

If the area is cold it speeds up the molecules and then it adds horsepower. If the area is hot then the area expands and then the molecules must cover expanded area.

I hope i didn't lose you.

N2O is not flammable, but will blow up when the tank is extremely heated and will be a not beatuiful sight.

[FastCougar]

Before I installed my ZEX kit, I educated myself for 3 months and read everything and anything I could lay my hands on. I have two rather large books at home discussing nitrous use in cars as well as a video tape produced by a drag racer. I know just about anything there is to know about nitrous systems.

The danger in using nitrous is not from the mixture itself, but from the container in which it is housed. If nitrous oxide was not compressed, it would exist in a gaseous state and the bottle would hold next to no nitrous. By compressing nitrous oxide, you change the state from gas to a liquid and can therefore store much more nitrous and wallah ... instant means of moving it from point A to point B ... via pressure. This pressure is not something to mess with. Overfilling bottles is VERY bad and should not be attempted. Doing so on warm days can cause the pressure in the bottle to reach it's rupture point. 12 lbs. of liquid nitrous in a 10 lb. bottle has a dramatic effect on bottle pressure. While I am on the point, bottle weights are not the weight of the bottle, that is merely a measurement of how much liquid nitrous the bottle can hold. The bottle itself can weigh quite a bit. For example, a 10 lb. nitrous bottle may weigh 18 lbs. empty, but filled to it's designed capcity, it will weigh 28 lbs.

Leave a bottle heater on or get into a rear end accident with a full bottle of nitrous and you are in for quite a shock as to what kind of damage a small metal bottle can do. It essentially becomes a high velocity projectile. Just as the pressure in the bottle pushes the nitrous though the lines and to the intake manifold at the other end of the car, that pressure escaping the bottle through a hole will move the bottle. Keep in mind that this isn't because the bottle is "exploding" in the traditional sense of the word, it's because the pressure is so great that it causes the bottle to completely rupture and as the liquid expands to "boil" off as a gas, propulsion is the result. Remember when you where a kid and you would blow up a balloon, pinch off the tip and then let it go and watch it fly across the room ... same thing, different materials. Now instead of a rubber object flying around, you have a 15 lb. metal bottle flying out of your trunk. THAT is why you never want a nitrous bottle within the cabin of your car.

This is what happens when you mis-wire your bottle heater so that it can be turned on with the car off ... it should have been wired to a switched power source. This guys' 91 Maxima was totaled because he accidently turned on the bottle warmer without knowing about it and 3 hours later, the pressure got so great that the bottle ruptured and "exploded" (no fire damage because it didn't actually exploded, which implies fire/combustion).

http://www.enhancedhealth.com/explosionPic1.jpg

And now, the remains of the nicely "unwrapped" bottle:

http://www.enhancedhealth.com/explosionPic11.jpg

Now, imagine trying to explain that one to your insurance company! :rofl:

Unfortunately for this dumbass, his car was in his garage and it sent his rear quarter panel through the garage door and trunk up into the ceiling doing quite a bit of damage to more than the car itself.

http://www.enhancedhealth.com/explosionPic2.jpg

Luckily for him and his family, nobody was nearby. The entire problem can be traced back to the fact that his bottle heater was installed improperly.

Any more questions?

[Jagular]

That little incodent could have been avoided had the guy spent the money and got the little $30.00 IHRA safty mandated blow off valve. At 3000lbs the little blow off valve lets go and lets all the nitrous out without exploding the bottle

[Aries]

I believe the guy did have one installed. the Nitrous Company is not taking repsonsibility for it though, because they said he disassembled and reassembled the valve, which caused it to malfunction... there's a site that's pretty popular that has the information on this guy's case.

[DanG]

Pinebox:

Bit of misinformation with your statement- Nitrogen is no "colder" than the matter surrounding it. It is the effect of Volume, mass, temperature, and pressure. The equation of all four of these elements always has to balance- For a given mass of gas, you can increase temperature to increase pressure while keeping volume the same. If you decrease temperature without messing with volume, you decrease pressure. In the application of nitrous, you increase the VOLUME. Since the mass and pressure remain the same, temperature DECREASES, quite rapidly. The gas is "sucking up" all of the heat energy it can as it expands in the environment to which it's been injected. It's an endothermic reaction- Everything around the nitrous (in this case, the intake stream) become very cold.

Likewise, the opposite occurs in the combustion chamber.

The combustion chamber equation looks like this at temperature of dissocation:

2N20 + heat = 2N2 + 02

The heat is caused by compression - Again, the whole volume, temperature, and pressure relationship. You decrease the volume without decreasing the amount of gas that's present. Temperature skyrockets, and bam- The N20 dissocates.

Then, the fuel comes in, with the catalyst of the spark from the spark plug:

C8H18 + O2 + heat = C02 + CO + H2O

The carbon chains in the fuel use the increased oxygen content to combust at a greater rate than that of "naturally aspirated" engines. Hence, the argument that nitrous really falls into the catagory of "forced induction". You spray (i.e. force) catalyst (O2) into the normal air/fuel combustion environment.

The problem is then left- Where did all the nitrogen go? The answer is two-fold. First, over 70% of the air we breathe is nitrogen- Diatomic nitrogen (N2), which is very stable. There is a very high temperature of dissociation for plain nitrogen, but it does happen- The nitrogen dissociates, and it gobbles up oxygen whereever it can get it- Hence nitrogen oxides. This reaction is unfavorable, and is a sign of incomplete combustion (just like CO - Carbon Monoxide). This is what the sniffer checks for at your local emissions station- NOXs, CO, and unburnt HCs (hydrocarbons).