Quote:
Originally Posted by cyberia
Jim, is that 300% expansion rate correct? Sounds over the top to me, but I have nothing to confirm or dismiss it.
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More or less. If the temperature is constant (which it isn't in this system as the temperature at high altitudes is generally much lower) then Boyle's law tells us that Pressure x Volume is constant. So if the pressure is reduced to one third of its original value then the volume will triple. The problem is that the temperature also goes down at the altitude, and lower temperatures cause the Pressure x Volume constant to decrease as well.
The combined gas law is as follows:
84ac3c18f6ab47f5085ddb5b8d62d760.png
where P=Pressure, V=Volume, and T=Temperature.
In an unpressurized cabin, pressure goes down, causing volume of gas inside a hollow viscous like the gut to go up. But the reduced temperature mitigates that effect some.
Where's P-D when we need him? He could explain this a lot better than I can.