Negative pressure from vacuum to shunt a object upwards?

AI Thread Summary
The discussion explores the concept of using negative pressure to create an upward force in a vacuum airship design, which aims to transport goods to inaccessible areas. The proposed design features a cylindrical body with a vacuum at the top and a wider base, suggesting that removing the lid would create a momentary upward force due to atmospheric pressure differences. Two potential outcomes are considered: one where the rig is shunted upwards due to negative pressure and another where it simply shakes without any net upward force. The feasibility of maintaining a vacuum and the materials required for construction are acknowledged as challenges. Overall, the idea presents an innovative approach to aeronautics, though practical implementation remains uncertain.
nightsdawnfan
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Hi folks,
I think a lot about aeronautics and physics for the purposes of helping people. I stumbled across the idea of vacuum airships as a cheap method of transporting food and water to places where it's unsafe for vehicles, or where there are no roads. We all know it's unconventional and uneconomical to sustain a vacuum -- carbon fiber and specialized materials are expensive even if you have a working design. My next idea is the principle of negative pressure. For thought, just imagine a tall cylindrical body with two parts to it. The bottom is the place where you put things and the bottom face is wider than the top. The top is empty with walls thick enough to handle rapid changes in pressure and covered with a lid. The top portion is a envelope with vacuum. The whole thing is beaker shaped. Next, imagine this setup is lifted onto a crane above the ground to rest. At this point, "with the snap of a finger" let's make the lid disappear.

What would happen?
A) The rig is shunted upwards due to the negative pressure due to a momentary upward force.
* Atmosphere above fills the void
* Atmosphere underneath (at a higher pressure because it's lower relatively) pushes up to fill the void
* Rig experiences a net force upward force due to the negative pressure
* Newtons law allows the net up force because the higher pressure of air below relative to the void.

B) The rig just shakes up and down briefly
* The atmosphere above collapses on the void equal to the atmosphere below
* Result is no net up force even including for the momentary buoyant force

Thanks
Nightsdawnfan
 
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Likes nightsdawnfan and OmCheeto
I will work on one, will try for a post later tonight.
Thanks
Nightsdawnfan
 
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