[HN Gopher] Vacuum Balloons (2020)
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Vacuum Balloons (2020)
Author : amichail
Score : 48 points
Date : 2023-02-12 13:13 UTC (9 hours ago)
(HTM) web link (www.salon.com)
(TXT) w3m dump (www.salon.com)
| DonHopkins wrote:
| Sounds like a bunch of hot air.
| Robotbeat wrote:
| This is pretty silly, they didn't even show a picture of the
| prototypes (which don't work) in the news article.
| ajuc wrote:
| They would just look like spheres?
| Robotbeat wrote:
| Not likely if they're vacuum.
| dreamcompiler wrote:
| 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.
| rnitchy wrote:
| carbon nanotubes, the answer is always carbon nanotubes
| ;)
| marcosdumay wrote:
| Like some foamy spheres. I couldn't understand if foamy
| spheres with a plastic film around them or just foamy spheres
| with self-contained holes.
|
| Oh, and on the color of aerogels.
| rnitchy wrote:
| 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
| rexreed wrote:
| A picture is worth a thousand words. This would be the literal
| case for this article. Perhaps 2,000 words.
| ChuckMcM wrote:
| 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.
| [deleted]
| quirkot wrote:
| 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.
| aardvarkr wrote:
| 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.
| RC_ITR wrote:
| 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.
| guenthert wrote:
| Hope is hardly a strategy. Long term technological progress
| depends on social stability and economic prosperity and
| those are all but certain.
|
| Humans had thousands of years experience having fun w/o
| wasting non-renewable resources.
| RC_ITR wrote:
| > Humans had thousands of years experience having fun w/o
| wasting non-renewable resources.
|
| Genuinely curious, are you speaking of pre-Bronze Age
| civilizations?
| quirkot wrote:
| 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.
| throwaway68979 wrote:
| Or society vastly underfunds science even though it's
| important.
| photochemsyn wrote:
| 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.
|
| Fun at parties? Bad idea most likely.
| BenjiWiebe wrote:
| Straight hydrogen balloons are probably still too flammable
| for parties but they poof instead of kaboom.
| af3d wrote:
| 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.
| gnopgnip wrote:
| Doubling the length of the structure would quadruple the weight
| but increase the volume contained eight times.
| jws wrote:
| 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.
| [deleted]
| aaron695 wrote:
| [dead]
| dreamcompiler wrote:
| 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.
|
| The book is about much more than that though.
| [deleted]
| raylad wrote:
| The idea is much older:
|
| First proposed by Italian Jesuit priest Francesco Lana de Terzi
| in 1670...
|
| https://en.wikipedia.org/wiki/Vacuum_airship
| darknavi wrote:
| It's funny that you mentioned Neal Stephenson because when I
| read "vacuum balloons" I thought about the Luk (onion) space
| suites from _Seveneves_.
| dcminter wrote:
| One also crops up in Banks' "Feersum Endjinn" which I think
| pre-dates it by a couple of years?
| messe wrote:
| Not just Endjinn, I think vacuum dirigibles are mentioned in
| a few of the Culture novels.
| throwaway68979 wrote:
| There are airships and dirigibles, but not vacuum ones (or
| at least, it's not mentioned they are) IIRC.
| h2odragon wrote:
| 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.
| pixl97 wrote:
| Djinn of technology, I expect we'll see that next when
| someone hooks a LLM to a 3d printer.
| [deleted]
| euroderf wrote:
| And will busted-off pieces float forever, presenting obstacles
| to navigation ? They will need to degrade in wavelengths found
| at altitude.
| krisoft wrote:
| 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.
| dreamcompiler wrote:
| 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.
| last_one_in wrote:
| 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.
| binarymax wrote:
| Why rule out hydrogen? In small quantities it's probably not that
| dangerous, and it's cheap to manufacture.
| jws wrote:
| 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.
| mrandish wrote:
| 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.
| simplicio wrote:
| Yea, Birthday parties mixing small kids, paper decorations,
| candles and hydrogen balloons seems like a questionable idea.
| xwdv wrote:
| He wasn't asking if we should, he was asking if we _could_.
| KrugerDunnings wrote:
| 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.
| SnowHill9902 wrote:
| 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.
| KrugerDunnings wrote:
| Please don't judge my theoretical ideas by your low
| engineering standards.
| jagged-chisel wrote:
| I think your detractors are reading snark where humor is
| more likely.
| nickparker wrote:
| 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.
| bell-cot wrote:
| Vacuum balloons for children's birthday parties???
|
| I'm seeing serious safety issues. No sign that they are.
| tlb wrote:
| 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.
| bell-cot wrote:
| 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.
| jagged-chisel wrote:
| 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.
| ricardobeat wrote:
| 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 voila. UFOs!
| Robotbeat wrote:
| You can do all of that using helium (or hydrogen...) plus it
| actually works. (China's recent balloon shot down over Myrtle
| Beach didn't use propellers, but others have:
| https://twitter.com/mrjeffu/status/1621728807609843718?s=20&...
| )
| madaxe_again wrote:
| 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.
| phyzome wrote:
| Even better, when the helium runs out, they're going to buy
| _hydrogen_ balloons. Much safer. :-)
| madaxe_again wrote:
| 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.
| BenjiWiebe wrote:
| 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.
| ordu wrote:
| Hydrogen balloon is being put on fire (and a balloon with 2:1
| hydrogen-oxygen mixture):
| https://www.youtube.com/shorts/_RKdWYqgu3Y
| __MatrixMan__ wrote:
| 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.
| beebeepka wrote:
| Party balloons is on par with leaf blowers and plastic, single-
| use utensils and containers.
|
| I cannot believe these things are encouraged and cheap to buy.
| What a waste for almost zero actual value
| Turing_Machine wrote:
| Obviously the people who buy these things find value in them.
| Otherwise they wouldn't buy them.
| voldacar wrote:
| If only we had a way to assign finite resources demanded by
| multiple agents
| quirkot wrote:
| This whole problem would be resolved if we could get it on
| the blockchain
| mjhay wrote:
| 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.
| mhb wrote:
| tldr:
|
| "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.
| mjhay wrote:
| Sounds like they built a novel kind of vacuum chamber.
|
| A larger balloon would have larger compressive stress over its
| entire surface. I'm very skeptical that could ever be made to
| float.
| raydiatian wrote:
| We fail to give up the most irrelevant things at the greatest
| cost.
| bilsbie wrote:
| 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.
|
| - dead poets society
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