h a l f b a k e r yWhere life imitates science.
add, search, annotate, link, view, overview, recent, by name, random
news, help, about, links, report a problem
browse anonymously,
or get an account
and write.
register,
|
|
|
|
The interior volume of the [VAB] building is so vast
that it has its own weather, including "rain clouds
forming below the ceiling on very humid days",
which the moisture reduction systems are designed
to minimize |
|
|
Silver coat the Mylar Balloons inside? |
|
|
The balloonists inside this huge hot air balloon are not going to like it. They are breathing hot air, after all! And the hot air inside their own balloons needs to be quite a bit hotter.... |
|
|
Bazinga! score 1 for [Vernon] |
|
|
Interesting how that fact slipped right past us. |
|
|
So if the internal temp of the enveloping balloon is
120 °C (250 °F) [max] then do the smaller internal
balloons need to be an additional 120 °C (250 °F) to
float inside? Or would an extra 10 degrees be enough? |
|
|
I think that's great because the smaller hotter balloons can work at keeping the large volume of the balloon at working temperature. I don't know about the balloonists though, maybe they will be in special self-contained suits, or be remotely controlled balloons. |
|
|
The "balloonists" will need environment suits
pure water
vapour at 100 C has no free oxygen, and would severely damage
mucous membranes. |
|
|
The heat loss through the envelope, particulaarly when it rains,
will be considerable. The bigger the envelope, the better. |
|
|
Condensate will form continuously over the entire inner surface,
and will add to the weight of the envelope. |
|
|
What is the heat source for the inner balloons, since there is no
free oxygen to support combustion? Are they to carry hydrogen
and oxygen in pressure vessels? |
|
|
"Buckminster Fuller proposes the "Cloud Nine" project, a levitating city of tensegrity spheres, each a mile in diameter. Because the surface-to-volume ratio of such spheres would be vanishingly small, Fuller calculated that if trapped solar energy raised their internal temperature by a mere one degree, they would be able to float like balloons." |
|
|
So a double hull encapsulating a vacuum would minimize heat loss and the temperatures in the lowest portions of the sphere should be livable. Condensation could be stored as ballast or ejected. |
|
|
I surmise that a helium balloon inside of another
helium balloon would sink within the outer balloon
and never rise to the top under any circumstance.
But as always, how the laws of physics are applied is
always Flying Toasters job to decide. |
|
|
There's no mention of a helium balloon. |
|
|
What are you the helium police? I know that. I'm just
curious, would a helium balloon float within another
helium balloon? Its a thought experiment and I'm
bored. |
|
|
The inner balloon would not float inside the outer balloon. |
|
|
hmmm, if the outer balloon were inflated to a greater pressure than the inner one it should... shouldn't it? |
|
|
Now back to the idea... I almost posted this same idea once, that's when I found the Cloud 9 reference, and I would So like to see it built in my life-time. |
|
|
No the important factor is the lightness of the gas. Helium floats in air because it is lighter than air. It would be interesting to inflate an outer balloon with air, and a smaller inner balloon with helium as a way of saving helium. |
|
|
But, if the outer balloon were inflated to a greater pressure then the gas would be more dense in the outer balloon than the inner balloon and, the inner one should rise within the outer one shouldn't it? What am I not understanding? |
|
|
On second thought you might be right. However on third thought the pressure of the inner balloon would be the same as the outer balloon if it is inside of the outer balloon. How could the inner balloon possibly maintain less pressure than a surrounding balloon with greater pressure? The inner balloon would compress equalizing to the same pressure. |
|
|
rcarty's right 2fries, the pressure of the outer
compresses the inner, thus negating the pressure
differential required for buoyancy. |
|
|
We digress however. What about the lightning. We
can use hydrogen balloons to float inside a hot air
balloon and watch the lightning storms! yeah us! |
|
| |