On 31 Oct 2003 04:49:23 -0800, (basskisser) wrote:

Steven Shelikoff wrote in message ...
Rod McInnis wrote:
"basskisser" wrote in message
om...


That has absolutely nothing to do with the fact that that nitrogen
doesn't expand at the same rate as oxygen for any given temperature
change. Do you deny this?


Yes. I deny this.

Mr. Boyle denies this. Mr. Charles denies this. Mr. Gay and Mr. Lussac
deny this. They wrote laws of physics about it. Every chemistry, physics and
thermodynamics class uses these laws. Here, don't take my word for it, let's
take a look at some of the information available from the net.

As an example:

Department of Chemistry
California State University, Sacramento
http://kekule.chem.csus.edu/gaslaws

You might as well give up now. No matter how much proof you provide,
basskisser will not believe it and will find some way to weasel out,
probably by saying he answered you in some other post without being able to
show where.

The thing I find amazing is that he claims to be a structural engineer, or
something like that. A professional engineer even. He is a sad testament
to whatever college he graduated from. This is basic high school physics
that is also reempasized in first year college engineering physics. For
him to be so blatently wrong in something that is so provable that he's
wrong and still not be able to admit it is just plain sad.

Boyles' law states that for a GIVEN GAS, the rate of expansion versus
temperature is inversely proportional. FOR A GIVEN GAS. It does not
state, however, that one gas expands as temp. increases, at the same
rate as another gas.

Very good. Now look up Charles' Law, V1/T1=V2/T2. Then the ideal gas
law, PV=nRT. And note that at low pressures (i.e., the pressures at
which are normally inside tires) all gasses act like ideal gasses and
have the SAME pressure vs. temperature vs. volume relationship..

Your phase change argument elsewhere is complete crap if it's meant to
show that nitrogen has a different PVT relationship vs. oxygen vs. air
at the pressures we're discussing. Now, I'll be nice and give you a
hint on how you could possibly defend your statement about air having a
less linear pressure temperature relationship then nitrogen: Look up
how much more or less ideal air is vs. nitrogen.

But even that argument has a problem in that 1) both of them behave like
an ideal gas at the low pressures we're talking about, where the
molecules are still far enough apart that their attraction doesn't
change the linear relationship PV=nRT. And 2) air is mostly nitrogen
anyway. So if you put both of them at a pressure where they deviate
from the ideal gas law (a very high pressure that would blow up most
storage tanks let alone any tire) they would both deviate from the ideal
gas law almost equally.

Keep trying.

Steve

On Fri, 31 Oct 2003 13:55:55 GMT, "Mark Browne"
wrote:

Rick and I just worked this out for water. In a race car tire that reaches
225 F to 250 F during normal operation, there *is* a phase change in water,
from liquid to vapor. The newly introduced water vapor can add a significant
component to the partial pressure composition of the tire. The only thing
left here is to determine how much liquid water might be found inside a tire
in different settings.

If there's any liquid water in the race tire/wheel at all, the tire
filler and wheel balancer should be fired. At the speed those tires
rotate, even a small amount of liquid water (say a few grams) would be
noticed as a vibration because the tire would be out of balance. It
doesn't get spread evenly around the inside of the tire.

Now in the temperature range of interest, operating tire temperatures, are
any of the materials you mention (Nitrogen, Argon, Oxygen) undergoing any
phase changes?
If not, do they show any appreciable deviation from the ideal gas properties
in the temperature range of interest?

It's pressure as well as temperature that would cause them to deviate
from ideal gas properties. And the pressures are not high enough.
Typically, you have to go above around 150 psi to notice any deviation
from the ideal gas laws. You have to go much higher than that for it to
have any appreciable effect.

As far as temperature is concerned, they deviate from ideal gas
properties at very low temperatures, temps near the phase change to
liquid. The higher the temp, the more ideal the gas behaves. If you're
only a few degress away from the phase change, you won't notice any
deviation from the ideal gas laws..

There is one other way a gas can deviate from the gas laws, and that's
at very small volumes. But the container must be so small that the
volume of the gas molecules themselves must be a significant portion of
the container. That is not the case with a tire.

If not, suck it up and move on.

Mark Browne
P. S. You would not be doing a Jax here, would you? That is, trying to
define the problem in such a narrow way as to give yourself a little wiggle
room. This is not necessarily a bad thing - some us miss toying with Jax!

At first, I thought he was Jax. But Jax at least had the courtesy to
confine the things he was wrong about to on-topic subjects. This idiot
is all over the spectrum.

Steve

basskisser wrote:

Yes, I agree, the level of scientific illiteracy is frightening. Here
you go, and Shelikoff, can you read this and comment??

There are several properties of gasses that can easily be demonstrated
using liquid nitrogen. These properties include phase changes (gas to
liquid, liquid to gas, and visa versa)

There isn't much new that can be added to your posts on this subject. I
first thought you were just argumentative and not too bright but now I
see that you are both argumentative and really stupid as well as curse
with a very short attention span and an obvious learning disability.

If you will reread or have someone read to you my post of October 28 at
8:56am message ID . net
you may gain a glimpse of the fact that this has already been pointed
out as a possibility for your inability to comprehend the subject.

Here it is again just in case you can't find the original.

------------------------------


I think most of this nonsense about nitrogen in tires not expanding as
much as air comes from the fact that few people really understand the
properties of gases. There is a little phrase in the gas laws that
refers to "phase change" ... that is where the followers of the myth may
be running aground - (boating content).

Liquid nitrogen will vaporize to produce a volume of gas that occupies
about 700 times that of the liquid. Liquid oxygen will vaporize to
produce a gas that occupies around 860 times the volume.

Vaporization is the phase change. Once the liquid has evaporated the
resultant gas, nitrogen, oxygen, or water vapor, will follow the gas
laws and when the correct law is applied (there are several) the
properties of those gases are very predictable and if you understood
them you would see that the properties of those gases are identical in
their behavior under the conditions which race car teams and trailer
boaters operate.

-------------------------------


I give up Basskisser, it has become obvious you are not really
interested in learning anything but are simply looking for a fight,
trolling, or just too thick to benefit from a discussion in which you
are ill equipped to participate.


Rick

"basskisser" wrote in message
om...

There are several properties of gasses that can easily be demonstrated
using liquid nitrogen.

As I clearly stated, the ideal gas laws apply as long as you are NOT
operating in the temperature/pressure ranges that will result in a phase
change for the elements involved. For the pressure and temperature that a
tire will be exposed to the gas laws apply. Once you start talking about
liquid nitrogen we are clearly in the phase change realm.

You may also notice though that they will also expand a bit faster
than the heavier gasses.

No. They have a lower boiling point, and thus as you watch them react with
the surroundings they will start boiling sooner.
It takes a significant amount of engergy to make an element/compond change
state. Start with a mixture of elements/componds (assuming that they don't
react and form a new compond) that are all cooled below any of their boiling
points (the insertion into the liquid nitrogen) and then start adding energy
(remove it from the nitrogen, it absorbs energy from the surrounding air).
Track the temperature of the mixture over time. You will see a fairly rapid
and linear rise in temperature until it reaches a temperature where one of
the elments/componds changes state. At this point the temperature will
remain constant until all of the element has changed state. The temperature
will increase linearly again until the next state change temperature is
reached.

If you are comparing the rate at which such an experiment will inflate a
balloon, then a mixture that has an element/compond that changes state at a
lower temperature will certainly start inflating sooner and do it more
rapidly. This isn't a function of the gas, it is a function of the stage
change.

The differences in the expansion rate becomes
even more obvious if argon is available. Argon has a very small
difference between the freezing point and boiling point (4o C) thus an
argon filled balloon will expand very rapidly.


All elements/compounds expand as they transition into the gaseos state.
This is not universally true for the transition from solid to liquid. Many
elements/compounds, including water, have a "triple point", a
temperature/pressure combination that will allow all three phases to exist
at the same time. Predicting the exact expansion rates of a mixture where
multiple state changes are involved is a bit more tedious, although the
expansion between solid and liquid would be dramatically less than between
liquid/solid and gas.



Compare this to a
breath filled balloon or a balloon filled with a gas such as ethane

Stay above the boiling point of ethane and these two will behave the same.
Heat both balloons the same amount and they will both expand the same
amount.

Now, there is one characteristic that might lead you to a false conclusion,
and that is the rate at which the change occurs. If you took the two
balloons from a cool room into a warm room you might see one of the balloons
expand faster than the other. Leave them there until they reach
equilibrium, however, and they will both expand the same. This is due to
the thermal resistance. Just like aluminum heats up faster than iron.

Back to what I have been saying all along: PV=nRT. It works for the
temperatures and pressures that a tire will be operated at. It doesn't
matter what the gas is. If the volume stays constant, and you change the T
by x%, you change the pressure by x%. It is basic gas law, you should
have learned this in high school chemistry class.

"Del Cecchi" wrote in message ...


Please explain how now nitrogen and oxygen differ?

Mark Browne

Nitrogen has an atomic weight of 14 and oxygen is 16? I can live on pure
oxygen, but pure nitrogen will kill me?

Not only that.....

The nitrogen in normal "air" is responsible for a real strong "buzz"
(nitrogen narcosis, rapture of the deep, ect) when scuba diving below
depths of 130'. Too much oxygen at depth and you can die (Ox Tox).

Got to add a little some helium (15-30%) while removing same amount of
nitrogen to alleviate those little "problems" when deep diving.

Has anyone pointed out to "basskisser" the "air" we breath is 79%
nitrogen and 21% oxygen?
--
SJM

Hydrogen is even better yet (better heat transfer coefficient). It is what is
used to cool the 1000 megawatt generators at power plants as air can't carry the
heat from resistance in the windings away fast enough. Just watch out for
flames or sparks. Also hydrogen tends to diffuse through the tire so you have
to replenish it more often.

JJ

On Sun, 26 Oct 2003 00:00:08 GMT, "Lawrence James"
wrote:

They have it at race tracks. Otherwise you need a tank of it. Know anyone
in the hvac business, they use it to purge refrigerant lines while they
braze. Not really likely to help enouhg to be worth the trouble though.
The other posters are right, bigger wheels are the right solution.

"John Gaquin" wrote in message
...

"Wwj2110" wrote in message

nitrogen helps tires run cooler

How does that work?

JG




James Johnson
remove the "dot" from after sail in email address to reply

On Sun, 02 Nov 2003 00:31:47 +0000, James Johnson wrote:

Hydrogen is even better yet (better heat transfer coefficient). It is what is
used to cool the 1000 megawatt generators at power plants as air can't carry the
heat from resistance in the windings away fast enough. Just watch out for
flames or sparks. Also hydrogen tends to diffuse through the tire so you have
to replenish it more often.


Having worked in a 1000 MW generating station, I can safely say this is
doggie-donuts. I wouldn't have hydrogen (or any explosive gas) within
100ft of a high-power generator!

Lloyd Sumpter

Lloyd Sumpter wrote:

Having worked in a 1000 MW generating station, I can safely say this is
doggie-donuts. I wouldn't have hydrogen (or any explosive gas) within
100ft of a high-power generator!

Hydrogen cooling is pretty common. He isn't, however, thinking about
just where that heat in a tire is supposed to go.

It's not like there is a heat exchanger to remove the heat from the gas
that was heated by the rubber surrounding that gas to begin with.

Rick

On Sun, 02 Nov 2003 19:48:12 GMT, Rick wrote:

Lloyd Sumpter wrote:

Having worked in a 1000 MW generating station, I can safely say this is
doggie-donuts. I wouldn't have hydrogen (or any explosive gas) within
100ft of a high-power generator!

Hydrogen cooling is pretty common. He isn't, however, thinking about
just where that heat in a tire is supposed to go.

It's not like there is a heat exchanger to remove the heat from the gas
that was heated by the rubber surrounding that gas to begin with.

The wheel. I can see how the heat conductive properties of the gas can
make a difference conducting heat from the tire to the wheel at
different rates. Especially since the rubber itself isn't a good heat
conductor.

Steve

Steven Shelikoff wrote:

The wheel.

The area of the wheel exposed to the gas is so small compared to the
area of the tire producing the heat that I doubt it has much of any
practical value in dissipation of heat above and beyond air flow over
and radiation from the tire itself.

Though it doesn't apply much to boat trailer tires, the heat
conductivity of the gas would work against tire cooling in the case of
race cars and aircraft since it would serve to increase the rate of tire
heating in heavy brake application. Many aircraft tire failures are due
to overheated brakes, heating the wheels to the point of causing the
tires to blow out or burn, not from heat generated by the tires themselves.

Rick