Does that seem insurmountable? Large vacuum chambers are widely deployed in homes today, as thermoses and CRTs. As long as the structure punctures and leaks rather than fracturing suddenly, it doesn’t sound wildly unsafe.
Perhaps the toy would consist of bags of inch-diameter vacuum balls, the rupture of any one creating just a pop.
Both to look more like current helium birthday balloons, and for square/cube law reasons, I'm thinking the vacuum birthday balloons would need to be ~30cm diameter.
The fragile vacuum part of a thermos has far fewer cc's of vaccuum (vs. a ~30cm "balloon"), is inside a pretty tough shell, and kids usually aren't allowed to play with 'em. CRT's hold more vacuum, but certainly aren't something that kids get to play around with.
Vs. have you ever watched younger kids play with balloons? Consider the potential for ear injury, if Kid_1 breaks a 30cm vacuum balloon in close proximity to Kid_2's eardrum. Or how similar the broken pieces of a vacuum balloon might be to broken glass.
Kids play with current balloons because they’re elastic and bouncy. I think they would be bored of a perfect sphere that just hovers around the room.
Further, given that the vacuum balloons are rigid, I think it’s far more likely to take on a leak that fills the balloon rather quickly but not instantly. For argument’s sake, suppose one does fail suddenly- do we even know what that sounds like? I don’t think it could possibly be worse than a (thick enough) mylar balloon pumped up to two atmospheres and exploding. It’s not like suddenly there’s vacuum in the room.
To answer the question posed in the article: no. People are going to buy the helium balloon that costs 300x less than the highly engineered device made out of ultralight materials that could implode violently if improperly handled.
Party balloons don’t need replacing - they need banning. They use irreplaceable resources frivolously, and cause harm to wildlife and livestock, who almost inevitably end up eating the things.
Hydrogen gets a bad rap. For the quantity that you’d have in a party balloon - even a dozen of them together - it’s safe, particularly as you aren’t going to have a stoichiometric mixture inside a balloon. If you managed to light one, you’d get a small implosion - much less than from a vacuum vessel. They’d also deflate more quickly, and wouldn’t travel anywhere near as far when inevitably released.
You could even do instant balloons, which come pre-sealed and just require snapping a vessel within to generate hydrogen.
Uh... They aren't quite as safe as you're implying. Hydrogen is really easy to light, and if one balloon goes the others in the bunch will 100% ignite too. You still get a pretty good amount of fire per balloon, just not an explosion.
As a former pyromaniac I can assure you that a party balloon filled with hydrogen (or a "Hindenburg Bomb" as we called them) is a pretty underwhelming thing. It goes up in a whoosh, not a bang , not a billowing ball of flame, and the screw-around factor just isn't there. Like, what to you do with it besides let it go whoosh?
The only thing that's dangerous about them is how boring they are. You'll be graduating to more interesting forms of pyromancy (like trying to make a flame thrower out of a punching balloon) in no time.
There's an area NE of Seattle in the Alpine Lakes Wilderness that I've done a lot of hiking in. That puts it downwind. Every time I've been there, without fail, I've found multiple balloons. Sad to think of all that plastic pollution in an area with pristine rivers, lakes, and glaciers - and all for just the inane reason that people like floaty round things.
Medicine, law, business, engineering, these are all noble pursuits, and necessary to sustain life. But poetry, beauty, romance, love, (and party balloons) these are what we stay alive for.
Yes likely if they're rigid, which is the whole point of vacuum balloons. The trick is coming up with a material that is strong enough to withstand the atmospheric overpressure trying to crush it, while also being sufficiently lightweight.
how about this. lets assume a sphere or egg shape is strongest and hardest to crush. create a bunch of ultralight tubes that are 12-18 inched long and crescent shaped. they are grouped in sets of 6 or more and are all connected at top and bottom by a small plastic ring. you slide them into a party balloon. and then give it air pressure, allowing you to spread them out with 60 degrees in between each crescent like an orange with all the slices. then you slowly let out the pressure so the rubber conforms against the 6 curves an makes a sphere at atmospheric pressure. then you pull vacuum, or simply place a bunch in a vacuum chamber and tie them off or glue the opening using something that wont react with latex
In short, you construct a shape made of inflatable cells which, when pressurized, contort in such a way that a vacuum is formed in the space within the collection of cells.
The problem, though, is that the additional air needed to make the cells stretch away from the center (and thus make a vacuum) is greater than than the air ‘missing’ from the vacuum part.
In any case, it’s been tried before:
“Vacuum/heat formed cushion with pyramidal, inflatable cells”:
The rubber membrane between the spars will not withstand the atmospheric forces.
14 pounds per square inch is a lot of force. A reference example, when planing a nuclear detonation(a grim task to be sure) the 5 pounds per square inch isoline covers the area where all non hardened structures(houses) are assumed destroyed.
Neal Stephenson imagined these in The Diamond Age: After we developed the technology to grow pure diamond in any shape, we used it to create ultra-thin rigid shells for giant airships, pulled a slight vacuum inside, and they floated.
See also Fred Saberhagen's "Empire of the East," which pre-dates Banks.
His characters are non-tech but have a "Djinn of Technology" who can conjure things for them, but they haven't the understanding to ask for the right things or use them, at first. He has fun with it. Once they get a balloon in the air they ask for a rudder to steer it; and get the wrong kind.
A diamond vacuum balloon (or pieces thereof) would fall to the ground very quickly if it lost vacuum. If we ever developed this technology, regulators would probably object to such construction because of the potential danger of falling diamonds hitting somebody on the head.
This is also a thing in the diamond age! The book mentions that they have laws to regulate that packaging material has to be heavier than air to prevent floating garbage.
Alastair Reynolds (one of my favorite hard sci-fi authors) used the idea a few times as well. Mostly as a minor detail, but “A Spy In Europa” had cities supported by hyperdiamond vacuum balloons, which is a pretty great image.
This article wasn’t very convincing, but let’s play along: if this works it could make sci-fi floating devices a possibility.
A drone or other flying object could float by pulling a vacuum (also not really feasible with today’s pumps) and control it’s density, without the need for any kind of reservoir. Maybe just enough buoyancy to massively reduce the power and noise needed on propellers. Add some form of wireless energy transmission (laser?) to remove the battery weight and voilà. UFOs!
A 10 lb structure would have to displace something like 3500 liters of air (a cube with side lengths of about 5 ft). Maintaining a vacuum with such little material is highly unlikely, to say the least. Moreover, scaling the structure by a factor of 2 increases the weight by a factor of 8. So the researcher's claim that "in order to make them flow to air, we just need to make them bigger" just doesn't make much sense. The larger the "balloon", the LESS likely it is to be structurally feasible.
Also, maintaining vacuum is probably easier in larger units since the volume is increasing faster than the surface area. More gas intrudes, but there is much more space for it to intrude.
The wildcard is what has to change for the thickness of the shell as it scales. That either makes it work, or be infeasible. More research required.
Can I suggest an improvement? Vacuum is also a great isolator and combined this with an internal hot air balloon, the inside can be made lighter by using hot air with the same pressure but lower density. The air is way less dense in the stratosphere so there must be some kind of equilibrium that can be obtained that once an object is that high it requires little energy to keep it there. These kind of blimps only get more efficient the bigger they get.
I also have an idea for active vacuum isolation for housig, much better lifetime than passive vacuum panels. Too bad no known takes my vacuum engineering serious.
The answer to why none takes your vacuum engineering seriously is ironically in your username. Vacuum is a good thermal conduction and convection insulator in theory, but as soon as a little bit of moisture leaks into it, it’s toast.
Active vacuum insulation isn’t a thing because you need high vacuum to reduce thermal conductivity at all, because mean free path and therefore specific conductivity grows at the same rate density decreases until mean free path exceeds the characteristic length of your application.
Also, modern VIPs have decades of life if installed properly.
Ughhh. 3 paragraphs telling you: that thing you like is actually bad and you are personally responsible for ruining science. Then, oops, only 10% of helium use is for parties.
That’s a nontrivial amount of a resource that is a limiting factor to scientific research and other ambitions that aim for loftier goals than temporary amusement.
The current known helium reserves are estimated to last (at current consumption rates) for 100-200 more years. Fwiw, all this non-renewable talk is only true in a world without space exploration or fusion (two things that will hopefully be more common 100 years from now).
The noise about a shortage is because the US gov't decided to stop subsidizing storage and delivery of helium, and scientists untrained in economics see "losing a subsidy" as similar to "a shortage" since the net effect is the same - prices are rising.
Culling recreational use would add 10-20 years of supply, which is unlikely to be the 'make or break' bridge to fusion or space mining.
Let people have fun, it's arguably the meaning of life.
If I'm willing to pay as much for helium as someone trying to pursue some lofty science goal, then either you have vastly underestimated the importance of amusement or science vastly overestimates the importance of the lofty goal.
Honestly, if my niece's quinceanera balloons stop the world from being saved, there's something deeply wrong beyond my scope of helping.
Our helium supplies mainly come from oil drilling, which makes them a non-renewable resource. Once it is lost to the atmosphere it basically disperses into space. The problem here is that the US government built up a huge reserve of helium in the 20th century and then began selling it off at below-replacement prices, leading to vast amounts of the stuff being wasted. Meanwhile the oil and gas industry stopped capturing helium and let huge amounts of it go to waste. We got cheap helium balloons at our parties in exchange for major losses that will be difficult to make up (particularly as we wind down the fossil fuel industry in this century.)
One of my undergrad chemistry teachers got everyone's attention by bringing in three balloons - one full of hydrogen, one full of oxygen, and one full of equal parts hydrogen and oxygen. Then (using long sticks) he proceeded to ignite each one with a match. We could all feel the shock wave from the H2-O2 mix going off.
I just checked out a couple videos of hydrogen filled party balloons being lit. I think it’s safe to say it could be a pants wetting experience and likely ignite paper party decorations.
Since hydrogen is more buoyant than helium, I wonder if it could be mixed with something which reduces the flame? Either in the gas or in the outer layer of a two layer balloon.
It just seems like if a substitute for party balloons is needed then exploring alternate gas mixtures might be low-hanging fruit compared to engineering lightweight yet low-cost vacuum structures.
Hmmm, interesting. Not sure if it would be much use for balloons but if you could make vacuum sections for walls then you could make super insulated walls.
I first heard/thought about vacuum balloons when reading Diamond Age (which I can recommend as an interesting book!) and ran off and did a bunch of math and figured out how difficult they would be to build and use. However, on planets with a much denser atmosphere, they would be pretty handy. Having a platform hanging under, or sitting upon, vacuum balloons on Venus for example would make for a science platform that moved around the planet and could exist where temperatures were more amenable to current electronics.
For those wondering about "the math", the simple version is to find the nominal density of atmosphere at the altitude you want to sit, take your material of choice and it's density. And then use (material_volume x material_density) < (atmosphere_volume x atmosphere_density), the amount of vacuum you need is then (atmosphere_volume - material_volume). You can plot it out, for every gram of material you need x cubic centimeters of vacuum. If you can find a solution where the material properties allow it to withstand the pressure differential, then you can, in theory, demonstrate a vacuum balloon if you can build it.
Note that it will almost always be a spherical balloon as pressure on a sphere becomes compression strength of the material you're using.
Lifting gasses provide two things: lift (of course), but also structural integrity: their desire to expand reinforces the structure containing them. Vacuum provides slightly more lift than helium but also provides negative structural integrity, since the atmosphere is actively trying to crush the vacuum chamber. From all accounts it would be a seriously challenging materials science endeavor to build something that could withstand containing a vacuum without adding more weight than the gain in lift, so in practice it would be very difficult to realise the 16% lift improvement.
One method is to go bigger: because of things like the square-cube law, the lift provided by a vacuum container increases faster than the demand on structural integrity, so a sufficiently large container lets you use more conventional materials. It’s been a long time since I did the math and I wasn’t very confident of my calculations even then, but I vaguely recall if you used steel you’d be looking at containers with multiple cubic kilometers of volume or something - highly impractical.
Another approach is only using vacuum in the upper atmosphere. The pressure on the vacuum container is much lower up there so you would have less of a structural integrity challenge. You don’t gain as much as you’d think from this approach, however, because the positive structural integrity provided by the expansion of lifting gasses allows for containers that expand, increasing their volume in response to lower air pressure (we call these containers “balloons”). In fact, because of this property, to a first approximation altitude has NO effect on the lift provided by a set amount of lifting gas (counter-intuitive, I know), and getting a helium balloon to STOP rising is a real challenge. Getting the vacuum chamber up high enough to make it safe to pull a vacuum is obviously a bit of a chicken-and-egg problem too, not to mention you’d have to bring the extra weight of a vacuum pump with you. Where this idea might work is if you’re coming in from space in the first place. Assembling the container in space means you don’t need a vacuum pump, and since you’re descending from above you don’t need a container strong enough to withstand containing a vacuum at sea level pressure. So this might have some use for putting floating structures into Venus’s upper atmosphere.
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[ 5.0 ms ] story [ 163 ms ] threadI’m seeing serious safety issues. No sign that they are.
Perhaps the toy would consist of bags of inch-diameter vacuum balls, the rupture of any one creating just a pop.
The fragile vacuum part of a thermos has far fewer cc's of vaccuum (vs. a ~30cm "balloon"), is inside a pretty tough shell, and kids usually aren't allowed to play with 'em. CRT's hold more vacuum, but certainly aren't something that kids get to play around with.
Vs. have you ever watched younger kids play with balloons? Consider the potential for ear injury, if Kid_1 breaks a 30cm vacuum balloon in close proximity to Kid_2's eardrum. Or how similar the broken pieces of a vacuum balloon might be to broken glass.
Further, given that the vacuum balloons are rigid, I think it’s far more likely to take on a leak that fills the balloon rather quickly but not instantly. For argument’s sake, suppose one does fail suddenly- do we even know what that sounds like? I don’t think it could possibly be worse than a (thick enough) mylar balloon pumped up to two atmospheres and exploding. It’s not like suddenly there’s vacuum in the room.
Party balloons don’t need replacing - they need banning. They use irreplaceable resources frivolously, and cause harm to wildlife and livestock, who almost inevitably end up eating the things.
You could even do instant balloons, which come pre-sealed and just require snapping a vessel within to generate hydrogen.
The only thing that's dangerous about them is how boring they are. You'll be graduating to more interesting forms of pyromancy (like trying to make a flame thrower out of a punching balloon) in no time.
I cannot believe these things are encouraged and cheap to buy. What a waste for almost zero actual value
"But Beaux noted that these small-scale prototypes were not air buoyant.
"We've demonstrated that we can build them, we can pull vacuum, but in order to make them flow to air, we just need to make them bigger," he said."
So, step two: profit.
A larger balloon would have larger compressive stress over its entire surface. I'm very skeptical that could ever be made to float.
- dead poets society
Oh, and on the color of aerogels.
This technique has promise.
In short, you construct a shape made of inflatable cells which, when pressurized, contort in such a way that a vacuum is formed in the space within the collection of cells.
The problem, though, is that the additional air needed to make the cells stretch away from the center (and thus make a vacuum) is greater than than the air ‘missing’ from the vacuum part.
In any case, it’s been tried before:
“Vacuum/heat formed cushion with pyramidal, inflatable cells”:
https://www.freepatentsonline.com/5596781.html
14 pounds per square inch is a lot of force. A reference example, when planing a nuclear detonation(a grim task to be sure) the 5 pounds per square inch isoline covers the area where all non hardened structures(houses) are assumed destroyed.
https://nukemap.org/nukemap/
The book is about much more than that though.
His characters are non-tech but have a "Djinn of Technology" who can conjure things for them, but they haven't the understanding to ask for the right things or use them, at first. He has fun with it. Once they get a balloon in the air they ask for a rudder to steer it; and get the wrong kind.
First proposed by Italian Jesuit priest Francesco Lana de Terzi in 1670...
https://en.wikipedia.org/wiki/Vacuum_airship
A drone or other flying object could float by pulling a vacuum (also not really feasible with today’s pumps) and control it’s density, without the need for any kind of reservoir. Maybe just enough buoyancy to massively reduce the power and noise needed on propellers. Add some form of wireless energy transmission (laser?) to remove the battery weight and voilà. UFOs!
The wildcard is what has to change for the thickness of the shell as it scales. That either makes it work, or be infeasible. More research required.
I also have an idea for active vacuum isolation for housig, much better lifetime than passive vacuum panels. Too bad no known takes my vacuum engineering serious.
Also, modern VIPs have decades of life if installed properly.
The noise about a shortage is because the US gov't decided to stop subsidizing storage and delivery of helium, and scientists untrained in economics see "losing a subsidy" as similar to "a shortage" since the net effect is the same - prices are rising.
Culling recreational use would add 10-20 years of supply, which is unlikely to be the 'make or break' bridge to fusion or space mining.
Let people have fun, it's arguably the meaning of life.
Humans had thousands of years experience having fun w/o wasting non-renewable resources.
Genuinely curious, are you speaking of pre-Bronze Age civilizations?
Honestly, if my niece's quinceanera balloons stop the world from being saved, there's something deeply wrong beyond my scope of helping.
Fun at parties? Bad idea most likely.
It just seems like if a substitute for party balloons is needed then exploring alternate gas mixtures might be low-hanging fruit compared to engineering lightweight yet low-cost vacuum structures.
For those wondering about "the math", the simple version is to find the nominal density of atmosphere at the altitude you want to sit, take your material of choice and it's density. And then use (material_volume x material_density) < (atmosphere_volume x atmosphere_density), the amount of vacuum you need is then (atmosphere_volume - material_volume). You can plot it out, for every gram of material you need x cubic centimeters of vacuum. If you can find a solution where the material properties allow it to withstand the pressure differential, then you can, in theory, demonstrate a vacuum balloon if you can build it.
Note that it will almost always be a spherical balloon as pressure on a sphere becomes compression strength of the material you're using.
One method is to go bigger: because of things like the square-cube law, the lift provided by a vacuum container increases faster than the demand on structural integrity, so a sufficiently large container lets you use more conventional materials. It’s been a long time since I did the math and I wasn’t very confident of my calculations even then, but I vaguely recall if you used steel you’d be looking at containers with multiple cubic kilometers of volume or something - highly impractical.
Another approach is only using vacuum in the upper atmosphere. The pressure on the vacuum container is much lower up there so you would have less of a structural integrity challenge. You don’t gain as much as you’d think from this approach, however, because the positive structural integrity provided by the expansion of lifting gasses allows for containers that expand, increasing their volume in response to lower air pressure (we call these containers “balloons”). In fact, because of this property, to a first approximation altitude has NO effect on the lift provided by a set amount of lifting gas (counter-intuitive, I know), and getting a helium balloon to STOP rising is a real challenge. Getting the vacuum chamber up high enough to make it safe to pull a vacuum is obviously a bit of a chicken-and-egg problem too, not to mention you’d have to bring the extra weight of a vacuum pump with you. Where this idea might work is if you’re coming in from space in the first place. Assembling the container in space means you don’t need a vacuum pump, and since you’re descending from above you don’t need a container strong enough to withstand containing a vacuum at sea level pressure. So this might have some use for putting floating structures into Venus’s upper atmosphere.
These people have not achieved it because it’s impossible to do in the real world. You need a material with almost no weight and infinite strength.
And after all that, the meme balloon only has slightly more lift then hydrogen. Could have just made a hydrogen balloon.
https://en.m.wikipedia.org/wiki/Aerographene
Train car imploding: https://youtu.be/Zz95_VvTxZM
Vacuum chamber imploding: https://youtu.be/qs6p8tPaur4