for what purposes is the pneumatic system used on a F1 car?

[hollus]

I am splitting this thread in 2. A very interesting discussion about whether engines produce max power at 10500 rpm or higher is now over here:
Max power, at 10500RPM or higher than 10500RPM?

[Tzk]

I believe they run pneumatic valve springs for three reasons.

1. efficiency+flexibility:
you can easily adjust the force-displacement curve with pneumatic spings. It isn't that easy with steel springs. You're also limited in the way regular springs act (force usually rises linear with displacement) vs. pneumatic springs (force rises exponential with displacement).

2. weight:
air is simply lighter than a steel spring.

3. valve oscillation:
You must use stronger springs to circumvent it and thus loose a tiny bit of power on the valvetrain.

[JordanMugen]

If the pneumatic pressure can vary the valve return, maybe they can use it as a variable valve timing?

Variable valve timing is banned in F1.

They run a long way from 14:1. Probably in the region of 22:1.

Yowzah!

[Jolle]

If the pneumatic pressure can vary the valve return, maybe they can use it as a variable valve timing?

Variable valve timing is banned in F1.

They run a long way from 14:1. Probably in the region of 22:1.

Yowzah!

Furthermore, valve timing is set by the cam shafts, not the spring pressure. The pressure must be high enough to always follow the cams. If they float, it’s the end of the engine.

[NL_Fer]

If the pneumatic pressure can vary the valve return, maybe they can use it as a variable valve timing?

Variable valve timing is banned in F1.

They run a long way from 14:1. Probably in the region of 22:1.

Yowzah!

Well not exactly timing, but i was thinking about variable pressure to achieve variable duration. Duration could be usefull to control this highly complex combustion process.

[hollus]

A reminder that I have split this thread in 2. A very interesting discussion about whether engines produce max power at 10500 rpm or higher is now over here:
Max power, at 10500RPM or higher than 10500RPM?

Discussion about pneumatic elements still feels at home here.