What a meal you guys are making of this. This is as simple as things get.
You make such a derogative comment on the topic and still get it wrong.
Whatever goes in, has to come out, unless there is somewhere in the cylinder than stores the air....quite unlikely.
It's not a air-pump it's a motor.
You add some fuel to the air and burn it. This changes some things mainly rising gas temperature. Otherwise the engine would not run at all.
You are also changing gas composition this might be insignificant but at least we should check for it.
Nevertheless you have higher air temperature and higher pressure when your exhaust valve opens. In the end a bigger volumetric flow passes through your exhaust pipe than through your intake.
The only problem we have is we don't really know the temperature but hey we could do a thermodynamic calculation to get it.http://de.wikipedia.org/w/index.php?tit ... 0302122730
We need temperature on point 4. Then we don't continue to go back to 1 because that would mean we are doing a closed process. We just continue with a constant temperature until we have 1bar pressure and calculate the Volume.
Anyone interested in?
From earlier calculations I think the temperature could be around 1000°K.
In the end it might be correct that we end up with a already posted speed but then we know it for sure.
The attempt from Ciro is to simple because it doesn't take into account the Volume rise. Furthermore I think the exhaust area is to big.
I would take 2 50mm pipes, makes about 39cm^2 compared to 100cm^2.