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And worth every penny!
Nitrogen Delema
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Joined
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1,304 Posts
Helium is an inert gas. Very safe.
Hydrogen is very "reactive". Not very safe. ("Oh, the humanity!")
In my introduction post I mentioned the most influence the pressure can have from water in the tire .
This needs for a tire with air volume of 3 moles ( pretty large tire i think about 18 gallons)at pressure 1 bar.14.5 psi,
about 54 gr/ml of liquid water in tire wich is 0.12 lbs ( convert yourselfes to gallons).
But howmuch water can get in the tire average when you fill it normally.
Suppose you fill with normal punp or compressor with no compression vessel.
Then the water in the outside air will get in the tire.
Asume filling to 2 bar/29 psi. when outside temp is 20 degrees C/ 70degr F, on a dampy day with humidity 100%.
Then the partial pressure of water is 0,02338504 bar/ 0,33917 psi.
I will go on in barr because thats easyer for me,
then the real pressure in tire will be 2+1=3 bar so 3 times 0,02338504 bar =
0,070155 bar of water in tire of wich 2/3th will condense .
For the 3 moll containing tire this will be 2x 0.0070155 mol of water wich is
times 18 gram = 0.25 gramm . so asuming 20 drops in a gramm = 5 drops of water.
So this is peanuts , but more important is howmuch the pressure can rise by that by the water only if temp in tire rises.
That is when 39degrC/about 105degr F belongs to 100% humidity 0.07 rounded then pressure rises only by water to 0.0467 bar/0.69 psi.
Above that inside temperature the pressure does not rise anymore only by the water , because all the liquid water has gone over to gas.
so also in normal filling use the effect of water is less then 1 psi .
Above that temp of 39 degr C the water gas expands the same as the other gasses, so no differce between dry air.
Then its possible by a delicate proces of temperature chanche of outside temp and humidity that by diffusion of the water as gas from outside to inside tire the amount of water gets more in the tire .
I think it would take years to get some more water in the tire by that process only when the car is standing still.
This would give more extra rising of pressure only by water in tire possible.
I already mentioned that if you are able to suck the tire vacuum, wich is as far as I read not possible, the liqiud water in the tire stays in because always under the niveau of the valve. So trying to get the water out by that wont work.
Now I am doing some out of the box thinking.
Trying to get as less water in tire , wont give you that much effect.
Better would be to take care, that while racing o the temp in the tire wont rise that much , so not 90 degrees C but only 40 degrees C for instance.
Most heat is produced when racing when braking to slow down for curves.
The old 2CV had the front brakes connected at the motor and so the wheels would not get that hot.
Other out of the box idea is to have water-cooled rimms.
Other is to blow cold air against the sidewalls of the tire , so aircondidioning that blows its air on the tires.
Read this all with a smile , but mayby some truth in it
This needs for a tire with air volume of 3 moles ( pretty large tire i think about 18 gallons)at pressure 1 bar.14.5 psi,
about 54 gr/ml of liquid water in tire wich is 0.12 lbs ( convert yourselfes to gallons).
But howmuch water can get in the tire average when you fill it normally.
Suppose you fill with normal punp or compressor with no compression vessel.
Then the water in the outside air will get in the tire.
Asume filling to 2 bar/29 psi. when outside temp is 20 degrees C/ 70degr F, on a dampy day with humidity 100%.
Then the partial pressure of water is 0,02338504 bar/ 0,33917 psi.
I will go on in barr because thats easyer for me,
then the real pressure in tire will be 2+1=3 bar so 3 times 0,02338504 bar =
0,070155 bar of water in tire of wich 2/3th will condense .
For the 3 moll containing tire this will be 2x 0.0070155 mol of water wich is
times 18 gram = 0.25 gramm . so asuming 20 drops in a gramm = 5 drops of water.
So this is peanuts , but more important is howmuch the pressure can rise by that by the water only if temp in tire rises.
That is when 39degrC/about 105degr F belongs to 100% humidity 0.07 rounded then pressure rises only by water to 0.0467 bar/0.69 psi.
Above that inside temperature the pressure does not rise anymore only by the water , because all the liquid water has gone over to gas.
so also in normal filling use the effect of water is less then 1 psi .
Above that temp of 39 degr C the water gas expands the same as the other gasses, so no differce between dry air.
Then its possible by a delicate proces of temperature chanche of outside temp and humidity that by diffusion of the water as gas from outside to inside tire the amount of water gets more in the tire .
I think it would take years to get some more water in the tire by that process only when the car is standing still.
This would give more extra rising of pressure only by water in tire possible.
I already mentioned that if you are able to suck the tire vacuum, wich is as far as I read not possible, the liqiud water in the tire stays in because always under the niveau of the valve. So trying to get the water out by that wont work.
Now I am doing some out of the box thinking.
Trying to get as less water in tire , wont give you that much effect.
Better would be to take care, that while racing o the temp in the tire wont rise that much , so not 90 degrees C but only 40 degrees C for instance.
Most heat is produced when racing when braking to slow down for curves.
The old 2CV had the front brakes connected at the motor and so the wheels would not get that hot.
Other out of the box idea is to have water-cooled rimms.
Other is to blow cold air against the sidewalls of the tire , so aircondidioning that blows its air on the tires.
Read this all with a smile , but mayby some truth in it
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