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Molecular Helium gas is injected into a hot liquid (plastic, rubber, etc.) at high pressure. Bubbles are ejected at the liquid-surface interface of various sizes influenced by nozzle design and gas velocity, etc. Some of these bubbles should be LTA and could be harvested (?vacuumed...screened for size?).
The liquid-helium bubbles solidify at STP and the encapsulated Helium is then at partial-pressure which further reduces the perfect bubble's weight. Only the selected "perfect" bubbles are harvested. The heavier bubbles return to the liquid. These LTA microspheres could be used to reduce weight in any enlosed space...packaging, wings, toys, etc.
Catch-a-Bubble
http://www.onlineto...ubble-pr-17559.html
Bubbles that 'set', as required by this idea. Just add helium! [neutrinos_shadow, May 20 2008]
microbubble aerosol
microbubble_20aerosol#1101954286
shameless self promotion [xaviergisz, May 20 2008]
[link]
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/The liquid-helium bubbles solidify at STP/ |
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The weight of the encapsulator will almost certainly offset any reduction offered by the helium. |
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{Lighter Than Air, Standard Temperature and Pressure(?)} |
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The helium would quickly diffuse outwards, methinks. Also, the bulk (adding all the particles together) surface area to volume ratio increases as you get smaller particles, so as they get smaller the weight contribution of the polymer increases and the spheres are subsequently weighed down. - |
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The dimensions of the "perfect" microspheres would be determined de facto...whatever works with the proper weight, surface tension, tensile strength, blah, blah, would be selected. They may be larger or smaller in scale depending on the material. Escape by diffusion of the small Helium molecule would need to be prevented by choice of material as well. This is tweak and fiddle science for sure! |
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You're much better off using hydrogen gas. By a factor of two, no less. |
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either way, I estimate that you'll be an order of magnitude or two away from actually getting this to work - even if you could get a nanometer-scale bubble surface film to solidify, it will be too fragile to do anything other than exist in a laboratory. Oh, an any gas light enough to have a shot at being LTA - will readily diffuse across any thin membrane. |
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It's almost like this isn't meant to work. |
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I used to work near a machine that fed helium-filled soap bubbles into a wind tunnel. The bubbles were about one-quarter-inch across, and were supposedly neutrally-buoyant. |
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This idea proposes a solid bubble skin, which is possible, possibly, but not that hard to think of. It's hard to make happen, though. |
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The description is messy and confusing. For instance, the bubble-maker does not need to be at high-pressure. |
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I think it is intended to solidify the bubbles at a temperature slightly higher than standard, so when the helium cools it is at reduced pressure, making a partial-vacuum sphere of each bubble. |
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We've done vacuum spheres, and can say that any advantage from partial vacuum is offset by the need for extra material in the shell. There might be some slight leakage-reduction advantage to having the helium at reduced pressure, but it will still diffuse outward over time. [-] |
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(-) for use of /..blah, blah../ |
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//but it will still diffuse outward over time// |
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ummm... but what will diffuse inwards to make up for the pressure loss ? or will the capsule gradually become a vacuum over time. |
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diffusion coefficients are inversely proportional to molecular weight |
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The membrane material needs to be impermeable otherwise you would be just as well off working on a zeolite aerogel, etc.
...the high jet velocity of helium injection was simply a method for creating a greater variety of gas bubble dimensions in terms of wall thickness, diameter, etc. |
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Molecular Helium was chosen as an inert gas vs. reactive Hydrogen while accepting the real but small increase in mass. |
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Nar, high jet velocity doesn't give all bubble sizes, and getting all sizes would be wasteful, anyhow. Figure out the optimal bubble size and thickness, and design the machinery for that. |
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Hydrogen isn't all that reactive, and most resins are much more flammable than it, anyhow. |
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