Here's a link to another article where the guy actually tested the pressure stability (versus temperature) of nitrogen, air, and CO2. His test showed little to no difference, but we don't know the moisture content of the "air" he used, so maybe there could be more of a difference under different circumstances.

http://www.powertank.com/truth.or.hype/

One potential problem I can see with too much water vapor in a gas used to inflate aircraft tires:
If an aircraft is flying in the extreme cold of high altitude, water vapor in a tire could condense into a liquid, and freeze into a puddle at the low spot. Might cause some tire imbalance if it doesn't have a chance to melt before landing.
Just taking some wild guesses...

 

A little more aviation nitrogen trivia: when I/we used air for servicing in aviation (tires, struts and accumulators) the compressor we used was equipped with a dehydrator to remove moisture. It was not absolute dry air as in 00.00% but pretty close. Nothing like what you imagine with a standard air compressor. They could also build 5,000 psi. B-52s and KC-135s were the only thing I ever used air on, everything else was always nitrogen and I would suspect B-52s/KC-135s have gone to nitrogen servicing by now as well. C-17s have an OBIGGS system that generates nitrogen to inert the fuel tanks. Now there is another cool science to talk about--molecular sieves also used to generate oxygen. All of the applications, had nothing to do with more "stable" pressures or less leakage and everything to do with moisture, corrosion and inerting.

 

 

OK, its been explained already that the nitrogen does not contain the moisture that ambient air does, but since you need it in wrtitting, here you go. Have you considered a career in the racing industry? Seems you know considerably more than the minds building these race cars.

Quote:

Complete article: http://www.getnitrogen.org/sub.php?view=nascar

NASCAR Information

Fundamentally; air, oxygen and nitrogen will all behave exactly the same in terms of pressure change for each 10 degrees of temperature change. However temperature alone is not the whole story.

Ambient air contains moisture, nitrogen does not. If moisture is present it contributes to a greater change in pressure simply because at lower temperatures water condenses to become a liquid. The liquid form of water occupies very little volume and contributes only a negligible pressure to the tire. But at higher temperatures, such as those in a running tire, water evaporates inside the tire and becomes a gas which increases pressure in the tire.

Ambient air contains about 21% oxygen. Oxygen’s smaller molecular size allows it to permeate through the rubber of the tire. By inflating with nitrogen, which is much less permeable than oxygen, the pressure changes due to oxygen loss are greatly reduced.

The racing industry is correct; nitrogen is more predictable. Because nitrogen is dry it has no moisture to contribute extra pressure changes with temperature. Because nitrogen permeates out much slower than oxygen pressure changes due to that leakage are almost eliminated compared with ambient air.

Let’s get a little deeper into the science. Keep in mind that the air in your tires changes about 1psi for every 10 degree temperature change. This means that a significant change in temperature will create a significant change in your tire pressure. Here is a set of Ideal Gas Law calculations showing the effects of a 10F degree temperature change on truck and passenger tires. The two sets of data represent different initial temperatures of 60F and 90F. This demonstrates that the magnitude of the pressure fluctuation differs depending on initial conditions but only slightly.


Calculate pressure change expected for each 10F degrees temperature change:

The final pressure is calculated based on the Ideal Gas Law where, for this discussion, P and T change while n, R, and V are fixed or constant.

The Ideal Gas Law equation is P*V = n*R*T where: P = pressure, T = temperature, V = volume, R = the ideal gas constant and n = the amount of gas in the tire in moles.

Using algebra to isolate the variables of interest, P and T, the equation becomes P/T = (n*R/V).

Therefore Pinitial/Tinitial = (n*R/V) = Pfinal/Tfinal since n, R, and V are all constant. That is, we assume no volume (V) change (i.e., no significant stretching of the tire rubber) and we consider the amount of gas in the tire (n) to be constant because the time frame is very short compared to the time it takes for gas to permeate through the tire rubber. The ideal gas constant, R, is by definition constant and therefore cannot change.

As we have shown above Pinitial/Tinitial = Pfinal/Tfinal. This can be rearranged algebraically to Pfinal = [Pinitial * (Tfinal/Tinitial)]. This allows us to calculate Pfinal by multiplying Pinitial by the ratio of Tfinal to Tinitial.

Note: temperatures must be converted to Kelvin units (K), from Fahrenheit units (F), for this calculation.

 

I'm getting well over 120k miles life out of my van tires when using nitrogen. Tires don't wear out only from wear from the road. They also deteriorate from the moisture and contaminants internally. Nitrogen almost entirely eliminates this factor. One source of information and service is www.nitrofill.com

 

Thanks, but I think that part was already understood. In a nutshell, dried nitrogen reacts to temperature changes the same as dried air. When either contains significant amounts of water, you get a new set of variables. Bottled compressed nitrogen contains less water than the air from a typical shop air compressor.

In other words, it's not the nitrogen itself which has greater thermal stability than air. It's the form in which it is supplied, with low water content.

The part I'm still not clear on is whether water vapor in the gas used to inflate a tire, under conditions where the water won't undergo a phase change from a liquid to a vapor (or the other direction), causes the pressure to vary more with temperature than if a super-dry gas was used. Thanks if you can clear that up.

 

No help here. That's above my pay grade. Lol

 

 

I drink it!!!

 

^ cute

nitrous oxide and nitrogen are not the same thing

and yes I know that is a sugar drink above