Replacement for air

[Lil Foot]

Tubes get very warm because of friction from constant rubbing inside the tire. Heat is the enemy of tubes.

Tire shops used to use tons of talcum powder because of this. Appears to be a lost practice these days.

 

[North Idaho Wolfman]

Well it just so happens CO2 and the minor component of R-404a absorb inferred heat and the major component of R-404a is used in fire suppression systems because it conducts heat away from burning material faster than it can be generated.

Ok it absorbs the heat, then what does it do with it?

 

[Oil pan 4]

Second law of thermal dynamics.
The heat from the hotter parts is going to flow to any cooler area. The R-404a is just the working fluid.

 

[armylifer]

Second law of thermal dynamics.
The heat from the hotter parts is going to flow to any cooler area. The R-404a is just the working fluid.

Okay, just for the record, I am not a scientist of any sort, and I don't pretend to be one but I want to know what happens to the heat that is transferred from the tube to the R-404a. The heat has to do something. It does not just disappear. If the heat is being absorbed by the R-404a, then something is happening with the R-404a molecules. They either have to expand, thereby creating a higher pressure in the tube or they have to escape into the atmosphere somehow. In any case, heat is not magically swallowed up by the R-404a.

If there is some voodoo here that you can make me understand, then I am all ears.

 

[Oil pan 4]

The heat will transfer from any warmer part to any cooler area, another part of the tube or tire, the wheel, or the surrounding area.

 

[tthorkil]

Since the R404-a is only in direct contact with the inside of the tube, I am guessing that the advantage of having R404-a to inflate the tube would be to help eliminate 'hot-spots' and more evenly distribute the friction generated heat?

 

[John Lash]

Refrigerant's "magic" quality is the ability to change state. From a liquid to a gas and then with the help from a compressor and a condenser from a gas back to a liquid.
In the process absorbing and releasing lots of heat.
No change of state no magic...
I don't believe you could measure any difference between a refrigerant gas and air.

 

[Oil pan 4]

Refrigerant's "magic" quality is the ability to change state. From a liquid to a gas and then with the help from a compressor and a condenser from a gas back to a liquid.
In the process absorbing and releasing lots of heat.
No change of state no magic...
I don't believe you could measure any difference between a refrigerant gas and air.

I have already destroyed one comment like this.
Go back and reread the other posts.

 

[armylifer]

I have already destroyed one comment like this.
Go back and reread the other posts.

I haven't read anything in any post on this thread that destroyed any comments concerning the difference between using air and your refrigerant - CO2 mixture. I still need convincing that pressures do not change with ambient air temperature or after the tires have been working for awhile. In fact, I believe that there would not be any difference in pressures between your mixture and just plain old air. I just gotta see proof!

 

[Oil pan 4]

I haven't read anything in any post on this thread that destroyed any comments concerning the difference between using air and your refrigerant - CO2 mixture. I still need convincing that pressures do not change with ambient air temperature or after the tires have been working for awhile. In fact, I believe that there would not be any difference in pressures between your mixture and just plain old air. I just gotta see proof!

Well it just so happens CO2 and the [R-143] component of R-404a absorb inferred heat and the [R-125] component of R-404a is used in fire suppression systems because it conducts heat away from burning material faster than it can be generated.

no need to adjust for pressure with temperature change unless you are going from Arizona to the artic circle. Plus I already tested the mix from 112°F to -10°F, pressure drop was on par with air or nitrogen. -10°F is as cold as it gets here about once every 5 to 7 years.

I already answered both those questions.

 

[William1]

Refrigerant's "magic" quality is the ability to change state. From a liquid to a gas and then with the help from a compressor and a condenser from a gas back to a liquid.
In the process absorbing and releasing lots of heat.
No change of state no magic...
I don't believe you could measure any difference between a refrigerant gas and air.

This.

Any gas has four qualities that should be considered when filling a tire. Does the gas affect tube/tire? Is the molecule size larger than the permeability of the rubber? Is it flammable? Does it expand or contract with heat/cold?

Still the best fill for a tire is nitrogen. Very large molecules. Inert. Non-Flammable. Very consistent and minimal expansion/contraction due to heating and cooling except at extremes.

Unfortunately as a tire fill, refrigerant by design has massive expansion and contraction with heat and cool (narrow temperature range from a gas to a liquid). Some refrigerants to attack certain rubber formulations though I believe all are fine around butyl.

 

[armylifer]

Quote:
Originally Posted by Oil pan 4 View Post
Plus I already tested the mix from 112°F to -10°F, pressure drop was on par with air or nitrogen.
End Quote:

You have already said once that the pressure drop of your mixture was on par with air or nitrogen. Therefore I cannot see any benefit to using your mixture.

Aside from the fact there does not seem to be any real benefit to using your mixture over the use of nitrogen, it is illegal to use any refrigerant in a non-recoverable manner. Since CO2 (R744) is also considered a refrigerant, the fact that you blended it with the R404a is also illegal, unless you are licensed to do so. Why would you advocate the use of a product that is illegal to use in the manner you have suggested, on a forum such as this one?

For purposes of research on the legality of using this mixture please refer to section 608 of the United States Clean Air Act.

 

[John Lash]

Originally Posted by Oil pan 4 View Post

Well it just so happens CO2 and the [R-143] component of R-404a absorb inferred heat and the [R-125] component of R-404a is used in fire suppression systems because it conducts heat away from burning material faster than it can be generated.

I thought refrigerant was used as a fire suppressant because it kept oxygen from the fire, and since it can be stored as a liquid you can get more volume in a container.

Perhaps your pressure doesn't change much because you are using such a small percentage of refrigerant.

But, hey maybe you have really discovered something...

 

[Oil pan 4]

Originally Posted by Oil pan 4 View Post

Well it just so happens CO2 and the [R-143] component of R-404a absorb inferred heat and the [R-125] component of R-404a is used in fire suppression systems because it conducts heat away from burning material faster than it can be generated.

I thought refrigerant was used as a fire suppressant because it kept oxygen from the fire, and since it can be stored as a liquid you can get more volume in a container.

Perhaps your pressure doesn't change much because you are using such a small percentage of refrigerant.

But, hey maybe you have really discovered something...

Fire suppressing agent also needs to take heat away from the burning material so it doesn't relight as soon as fresh air hits it. Just like water or cold liquid CO2 does while trying to flash to vapor.
That's why fire suppression systems don't just use nitrogen.

 

[Oil pan 4]

Quote:
Originally Posted by Oil pan 4 View Post
Plus I already tested the mix from 112°F to -10°F, pressure drop was on par with air or nitrogen.
End Quote:

You have already said once that the pressure drop of your mixture was on par with air or nitrogen. Therefore I cannot see any benefit to using your mixture.

Aside from the fact there does not seem to be any real benefit to using your mixture over the use of nitrogen, it is illegal to use any refrigerant in a non-recoverable manner. Since CO2 (R744) is also considered a refrigerant, the fact that you blended it with the R404a is also illegal, unless you are licensed to do so. Why would you advocate the use of a product that is illegal to use in the manner you have suggested, on a forum such as this one?

For purposes of research on the legality of using this mixture please refer to section 608 of the United States Clean Air Act.

I already have a recovery system.
Just like the F1 guys did. That's how they kept it legal.

Also R-143 is used to fill tires, gets blended with air all the time or CO2 some times, is used in all kinds of other non recoverable ways and no one gets their panties in a knot over it.