[Geezer]

"According to a number of websites it is the lack of change of pressure with temperature that is the key element for F1 tyres."
nitrogen ( like most gases) obeys this
http://en.wikipedia.org/wiki/Charles's_law
quite well for the sort of temperature and pressures in tyres

Yeah! It only took TNS 2.5 years to figure this one out!

It may have taken that long for you to post it, but it took rather less than a day for us to figure it out.

Actually, it's really four years including the previous thread []

Maybe we should have had it rethreaded?

[graham.d]

BC, the key factor is "DRY" not specifically the gas. With changing temperature the partial pressure from water vapour is VERY significant, especially in F1. I was aware of the gas laws! As I said DRY nitrogen is readily available.

The use of complex gases by Ferrari was to do with using the gases to cool the tyres (according to websites) by conducting heat to the metal part of the wheel.

[alanturing]

I don't think it have any effects

[Bored chemist]

Notwithstanding the fact that the "point" of f1 is to drive round in circles, they are not idiots.
They would know that you need to remove at least some of the water from air before pumping it into tyres (other wise you end up with some  liquid water in there which would be horrid).
As I mentioned a few years ago, just compressing the air, storing it in a tank , and then delivering it to a tyre at a lower pressure than the tank pressure would be sufficient to do that. The F1 folks would have worked it out too. They would know you don't need to use nitrogen, nor do you need very dry air.
Tyres run hot so the problem is even less stringent that it first looks.
As long as you don't reach the saturated vapour pressure, water vapour obeys Charles' law quite well too.

If Ferrari has looked at a table of gas properties that would have found that hydrogen and helium carry heat rather well.
The generators in my local power station were enclosed in sealed vessels full of hydrogen in order to cool them.
More complicated and heavier gases are generally going to be worse conductors of heat.
It's perfectly possible that Ferrari are deliberately misleading the opposition.

[Geezer]

I suppose the composition of the gas could increase the rate of heat conduction into the wheels, but would it make an appreciable difference? I'm not even sure they would want to do that. They seem to go to a lot of trouble to keep the tires as hot as possible.

[CliffordK]

Good point.  They at least like warm tires.

Conducting heat away from the brakes is another issue though.

If one is wanting to conduct heat from the tire to the rim, what about adding a layer of aluminum foil to the inner surface of the tires.