Do you use nitrogen?

[Gorilla]

<munching popcorn> This is a slow motion train wreck. Russian? Your turn.

 

[Headwind]

Race cars use nitrogen because the tire pressure will remain the same with high temps. Also, on a jet aircraft, how would you get 270 psi into your main tires with an air compressor?

HEADWIND

 

[mtrv]

Since I do have slow leaking aircraft tubes, and a bottle of nitrogen with regulators which is normally used for other purposes, I will now fill the tires with nitrogen.

This forum has served a purpose on this subject; and I report back in a few months to a year or two, to let you all know how the nitrogen has stood the test of time, compared to ordinary compressed air in a GA airplane.

 

[sleddriver71]

Whats wrong with Layman's terms?



You looked that one up for this didn't you? It takes a lot to bust my balls, huh?

Hello? Did I not say that? It takes large temperature changes to change the state of the gas.


More Wikipedia BS you really didn't know.

Uhhhh, it was ALL right.


For any other gas to get near the carcass of the tire, it would have to be trying to enter the tube. Hey moron, nothing is trying to come IN to the tire! Did you forget that the pressure in the tire is HIGHER than the outside air? Geez...try harder next time.

Jerk.

And another thing. You need to stay off my back. I am tired of you running your mouth about me. You don't know a lick about me, so shut it.

How old are you? Why are you such a sore loser? Why can't you learn to take criticism? Why can't you accept it when your wrong? Why do you have to let your bad temper show in your responses? Why can't you think straight when your flustered? Why don't you change your call sign? Why are you such a name caller? Why don't you grow up?!

 

[The_Russian]

<munching popcorn> This is a slow motion train wreck. Russian? Your turn.

I'll be back later, busy today.

How old are you? Why are you such a sore loser? Why can't you learn to take criticism? Why can't you accept it when your wrong? Why do you have to let your bad temper show in your responses? Why can't you think straight when your flustered? Why don't you change your call sign? Why are you such a name caller? Why don't you grow up?!

Old enough. I am not a sore loser. Nothing I posted was incorrect. And, that should be noted instead of me being ripped apart be someone who doesn't like me. I can take criticism but not from someone who is just doing it because they dislike me. A Squared has made that clear on previous threads. A bad temper in arguments and not being able to think straight when someone offends me emotionally are some of my downfalls. Every human has some of those. I will conceed that! I am not going to change my call sign because I am proud of where I have been in my life and stand for what I have done. I should not be ashamed of who I am because others don't like my career path. Name calling is fun. People call me names on here all the time if you haven't noticed. I don't think I'll ever grow up. I'm a Toys 'R' Us kid!

 

[The_Russian]

And BTW.... If A Squared was really interested in correcting those who were wrong on the subject for the benifit of this thread, he would have ripped apart the other ten posts that were wrong just like he did to mine.

 

[Andy Neill]

I don't know what the rest of you are breathing, but I breathe in over three times as much nitrogen than oxygen every day since the earth's atmosphere is 78% nitrogen and only 21% O2.

 

[Ralgha]

And BTW.... If A Squared was really interested in correcting those who were wrong on the subject for the benifit of this thread, he would have ripped apart the other ten posts that were wrong just like he did to mine.

Actually he did rip apart a few other posts, not just yours, however, you are the only one who can't admit that you were wrong.

 

[V-1]

Since I do have slow leaking aircraft tubes, and a bottle of nitrogen with regulators which is normally used for other purposes, I will now fill the tires with nitrogen.

This forum has served a purpose on this subject; and I report back in a few months to a year or two, to let you all know how the nitrogen has stood the test of time, compared to ordinary compressed air in a GA airplane.

Why not perform a controlled experiment? Inflate one main tire with ordinary air, and one with nitrogen. Take tire pressures before and after every flight. Record them carefully in a table or graph. Report back to us in twelve months on your findings. There might even be some government grant money available to finance your research (and as a side benefit, your flying)!

Around here, there is a retail automotive tire store chain that advertises "Nitrogen Inflation" as a significant benefit for cars...because the molecules are bigger and don't leak as rapidly as oxygen ones. It always makes me smile to think of the people who pay a premium for that 22% of gas in their tire that isn't oxygen.

I'm no gas expert (though I can hold my own against anyone when it comes to producing it) but it seems to me if oxygen molecules leak out faster than nitrogen molecules, at some point in time there would have to be a very small percentage of oxygen molecules remaining in a tire vs. the remaining nitrogen molecules.

 

[wrxpilot]

Race cars use nitrogen because the tire pressure will remain the same with high temps. Also, on a jet aircraft, how would you get 270 psi into your main tires with an air compressor?

HEADWIND

No, that is NOT why race cars use Nitrogen. ASQUARED is correct, all gasses follow the same law of PV=nRT. If temp goes up, pressure goes up. Do some aircraft tires really require 270 PSI? Well even if they do, there are air compressor systems that can easily handle it. Not every air compressor is like the one out in your garage.

Here's a link to Ingersoll Rand about the benefits of Nitrogen:
http://www.irtools.com/products/nitrogen/

 

[mtrv]

If temp goes up, pressure goes up.

Yes, but the statement is misleading. I'm going to use common refrigerent gasses for A/C units as an example.

R-22, which has been used for many years, will be running approx. 102 psi at 60 F. , while the new replacement freon, R410A will hit approx 170 psi at 60F. This is over 1 1/2 times the pressure, for the same identical temp. Increase the R-410A temp to 120F, and it's now 350psi, versus 260+ for the R-22. Needless to say, using freon, isn't the best for pumping tires that will tend to heat up, with some use.

These same differentials apply to Nitrogen and ordinary compressed air. However, I'm not in the mood to look up the exact differentials, so that I appear to be a walking encyclopedia. In the end, the pressure increase for nitrogen, as the temp. increases, will be less for nitrogen.

At least, I believe so! And no, I'm still not going to look up the exact differences.

 

[The_Russian]

Actually he did rip apart a few other posts, not just yours, however, you are the only one who can't admit that you were wrong.

What's wrong about my first post? Nitrogen does eventually freeze. I failed to state it would turn to liquid first. Am I the only one not taking crazy pills?

Nitrogen freezes at a lower temperature. It also retains a constant pressure over large temperature changes. On top of that it does not contain moisture, unlike the ambient outside air. If outside air is pumped into an aircraft that flies above the freezing level, the moisture within the air will freeze inside the tire. This can cause an imbalance or corrosion.

Also, aircraft tires are designed to resist nitrogen permeation though the carcass.

In its context for pilot information this is correct. If we get into the science of gas laws, the paragraph can be expanded on. If A Squared had the capacity to teach instead of insult, then he would have added constructive statements. Such as, "Russian, nice post. But I would like to add a few tidbits of info".

 

[wrxpilot]

Yes, but the statement is misleading. I'm going to use common refrigerent gasses for A/C units as an example.

R-22, which has been used for many years, will be running approx. 102 psi at 60 F. , while the new replacement freon, R410A will hit approx 170 psi at 60F. This is over 1 1/2 times the pressure, for the same identical temp. Increase the R-410A temp to 120F, and it's now 350psi, versus 260+ for the R-22. Needless to say, using freon, isn't the best for pumping tires that will tend to heat up, with some use.

These same differentials apply to Nitrogen and ordinary compressed air. However, I'm not in the mood to look up the exact differentials, so that I appear to be a walking encyclopedia.

Huh??

You're talking about a refrigerant system at particular operating temperatures and pressures. A very confused analogy to inflated tires. Your initial pressure for the tires will be whatever you set it at, regardless of temp. Here's how the gas laws work:

PV=nRT

Rearranges to P/T = nR/V

We're going to look at two different states of pressure/temperature:

P1/T1 = P2/T2
(n, R, and V cancel out as they are equivalent)

Initial conditions at Jim Bob's garage for the tire filling:
T1 = 20C = 293.1K, P1 = 80 psig

Now the tire is flying around in some airplane up really high:
T2 = -40C = 228.1K, P2 = ?

P2 = P1*T2/T1 = 62 psig

Notice there is nothing whatsoever related to the gas in the ideal gas law equation (Dry air and N2 are very close to being ideal gasses).

This is starting to sound like that stupid treadmill question, except this is even more ridiculous. Read the link I put on here earlier from Ingersoll-Rand.

After some reading, the benefits from Nitrogen are:
1)Reduced loss of pressure over time due to N2 having larger molecules than O2, which is apparently permeated through the rubber.

2)Reduced pressure differentials with temperature due to the lower water vaport content of pure N2.

Here's another link:
http://www.popularmechanics.com/automotive/sub_care_clinic/1272166.html?page=2&c=y

 

[mtrv]

Huh??

You're talking about a refrigerant system at particular operating temperatures and pressures. A very confused analogy to inflated tires. Your initial pressure for the tires will be whatever you set it at, regardless of temp. Here's how the gas laws work:

It's not confusing at all. In the days before high cost refrigerants, and the decision that some could lead to global warming; it wasn't uncommon to see a semi-flat tire pumped up with freon in an emergency; should you just happen to have some around. Just count on a rapid pressure increase, as the tire temp increases in road conditions, even though the initial pressure was at the tire rated pressure of 35 psi, at the particular ambiant temp. of the moment.

Now whip out your forumula's, and find the pressure increase for a racing tire thats been super heated since it's initial inflation. I want to see exact numbers comparing nitrogen & compressed air. Do nitrogen filled tires remain more stable in psi with increased temp ranges?

edit: I need to clarify this question slightly.

Since pressure does increase with temperature, then I can assume that the nitrogen filled racing tire is going to be cooler, than an air filled tire under the same racing conditions; which is the same as saying, that the nitrogen filled tire will have less pressure increase, as the outside ambient temps rise, while the vehicles sit motionless in the noon day sun.

 

[wrxpilot]

It's not confusing at all. In the days before high cost refrigerants, and the decision that some could lead to global warming; it wasn't uncommon to see a semi-flat tire pumped up with freon in an emergency; should you just happen to have some around. Just count on a rapid pressure increase, as the tire temp increases in road conditions, even though the initial pressure was at the tire rated pressure of 35 psi, at the particular ambiant temp. of the moment.

I think what you were seeing was the Freon expanding from a very high pressure tank to the relatively low tire. Expansion requires lots of heat, so the gas was very cold inside the tire. As it was driven around, it heated up such that there was a much bigger temperature difference than if it were air.

Now whip out your forumula's, and find the pressure increase for a racing tire thats been super heated since it's initial inflation. I want to see exact numbers comparing nitrogen & compressed air. Do nitrogen filled tires remain more stable in psi with increased temp ranges?

They do apparently remain more stable than the air ones, but still follow the ideal gas law. If the air was totally dry, they would both be very similar. The benefit you're getting is dryness - though I'd be surprised if there was any more than 5-10% difference. Water vapor is a very small component of the total pressure ratio.

edit: I need to clarify this question slightly.

Since pressure does increase with temperature, then I can assume that the nitrogen filled racing tire is going to be cooler, than an air filled tire under the same racing conditions; which is the same as saying, that the nitrogen filled tire will have less pressure increase, as the outside ambient temps rise, while the vehicles sit motionless in the noon day sun.

Not sure how the nitrogen filled tire is going to be cooler, you've lost me there. The tire heat is generated from friction between the tire and the road, and it is whatever it is.