3 ms·

Would another shape reduce the amount of surface area/external pressure? I've long dreamed of having one of these ships, but it doesn't seem to be in the cards

Would another shape reduce the amount of surface area/external pressure? I've long dreamed of having one of these ships, but it doesn't seem to be in the cards.

danbruc 12y ago
No, a sphere has the minimal surface area volume ratio. Wait, that does not really answer your question.
- valarauca1 12y ago
  Yes it does. It would be a major mathematical revolution if you discovered a new shape that exists in our world that has a better SA:V ratio.
  - olefoo 12y ago
    But SA/V isn't the important ratio here. The important ratio is weight to volume. Surface area only matters in terms of how much pressure the system needs to resist, and using compression members means you have some room to play with. But if you have a a structure from which you've removed the air that is too heavy to float in air you get no prize.
    - lutusp 12y ago
      > But SA/V isn't the important ratio here. The important ratio is weight to volume. Don't forget crush resistance with a minimum of construction material. But as it turns out, a spherical shell is the optimal shape for all the stated requirements -- it evenly distributes the compressive force across its surface, it represents the optimal ratio of surface area to volume, and it therefore follows that a sphere represents the smallest mass per enclosed volume. > But if you have a a structure from which you've removed the air that is too heavy to float in air you get no prize. That's certainly true. But for a vessel with a fixed wall thickness, making it larger greatly increases the chance that it will rise, because the enclosed volume increases so much faster than the surface area. This would all be easier on Venus, where the atmospheric pressure is vastly greater than here, but the gravitational force is less. If only it weren't so damn hot.
  - panzi 12y ago
    I think it is mathematically proven that that's a sphere. Once something is mathematically proven there won't be anything ever that invalidates this. Also: Imagine any shape. Now imagine to inflate it. What shape will it more and more approximate?

Would another shape reduce the amount of surface area/external pressure? I've long dreamed of having one of these ships, but it doesn't seem to be in the cards.

danbruc 12y ago

No, a sphere has the minimal surface area volume ratio. Wait, that does not really answer your question.

valarauca1 12y ago
Yes it does. It would be a major mathematical revolution if you discovered a new shape that exists in our world that has a better SA:V ratio.
- olefoo 12y ago
  But SA/V isn't the important ratio here. The important ratio is weight to volume. Surface area only matters in terms of how much pressure the system needs to resist, and using compression members means you have some room to play with. But if you have a a structure from which you've removed the air that is too heavy to float in air you get no prize.
  - lutusp 12y ago
    > But SA/V isn't the important ratio here. The important ratio is weight to volume. Don't forget crush resistance with a minimum of construction material. But as it turns out, a spherical shell is the optimal shape for all the stated requirements -- it evenly distributes the compressive force across its surface, it represents the optimal ratio of surface area to volume, and it therefore follows that a sphere represents the smallest mass per enclosed volume. > But if you have a a structure from which you've removed the air that is too heavy to float in air you get no prize. That's certainly true. But for a vessel with a fixed wall thickness, making it larger greatly increases the chance that it will rise, because the enclosed volume increases so much faster than the surface area. This would all be easier on Venus, where the atmospheric pressure is vastly greater than here, but the gravitational force is less. If only it weren't so damn hot.
- panzi 12y ago
  I think it is mathematically proven that that's a sphere. Once something is mathematically proven there won't be anything ever that invalidates this. Also: Imagine any shape. Now imagine to inflate it. What shape will it more and more approximate?