- #1
some bloke
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- 99
Vacuum airships are a scifi idea where you evacuate the air out of a chamber to achieve lighter-than-air lift.
I put this in scifi as it's just a curiosity at the moment.
The issue faced with these designs is the chamber buckling with the pressure of the atmosphere around it, which puts pay to it being lighter than air.
I realize that there is a theoretical maximum pressure difference the wall of a chamber can withstand before buckling - this represents the strength of the wall.
I'm wondering it would be feasible to use multiple layers of wall, with steadily increasing pressures inside, to prevent it from buckling under the strain.
Let's say that the wall can take 5psi before buckling. Atmospheric pressure is 15psi, so if it's fully evacuated, the chamber buckles.
now, if I wrap the chamber at 0psi in another chamber at 5psi. The pressure on the internal chamber is now 5psi, and the pressure on the outer is 10psi - so the outer would still collapse.
Add another layer at 10psi and you have 3 walls, each only taking 5psi, but with a vacuum on the inside. I don't know whether this would be any lighter than just making the chamber strong enough to withstand 15psi, but that's beside the point.
My question is - would this work? can you stagger the pressures via sequential containers? or am I missing something?
I put this in scifi as it's just a curiosity at the moment.
The issue faced with these designs is the chamber buckling with the pressure of the atmosphere around it, which puts pay to it being lighter than air.
I realize that there is a theoretical maximum pressure difference the wall of a chamber can withstand before buckling - this represents the strength of the wall.
I'm wondering it would be feasible to use multiple layers of wall, with steadily increasing pressures inside, to prevent it from buckling under the strain.
Let's say that the wall can take 5psi before buckling. Atmospheric pressure is 15psi, so if it's fully evacuated, the chamber buckles.
now, if I wrap the chamber at 0psi in another chamber at 5psi. The pressure on the internal chamber is now 5psi, and the pressure on the outer is 10psi - so the outer would still collapse.
Add another layer at 10psi and you have 3 walls, each only taking 5psi, but with a vacuum on the inside. I don't know whether this would be any lighter than just making the chamber strong enough to withstand 15psi, but that's beside the point.
My question is - would this work? can you stagger the pressures via sequential containers? or am I missing something?