There are some insulationpanels that claim to use vacuum technology.
Here is Consumer Reports take on argon in double pane windows. In short, adds about .5 R value but it’ll take a long while to pay back the extra cost.
I remember an old This Old House where the gas mix in the windows was special so that the up/down motion due to heating and cooling was minimized. This would require some gas that is not at all close to ideal which excludes argon and such. Color me skeptical.
Since most windows have an R-Value of around 3, adding R-0.5 is pretty significant.
The vacuum-insulated windows at the link in my post (#6) claim to be R-10.
That’s getting up there with the values for triple-pane windows.
Any electronics that uses valves will have a vacuum, things such as valve amps, some guitar pre-amps will have a valve stage to generate the type of overdrive that you can’t quite get any other way
I’m pretty sure that those Yeti/RTIC mugs are vacuum-insulated.
Your linked article says that most window manufacturers now use argon by default, so there’s no extra cost to pay back.
And what do you mean when you describe a gas as “not at all close to ideal?”
Yes, and regular incandescent light bulbs are in a vacuum too, but it’s not to increase thermal performance/insulation.
Isn’t thermal insulation exactly why they vacuum incandescent light bulbs (when they don’t fill them with Argon)? It’s to minimize loss of energy to heat so more of it goes to light.
They do fill them with argon or other gas such as Xenon. Vacuum incandescents were the original Edison bulbs, the vacuum and, later the noble gases, were/are there to prevent the filament from burning up (and away) from any oxidizing gases.
Apparently using a vacuum isn’t particularly common in modern bulbs since it doesn’t retard evaporation of tungsten filaments. That was more the case with older carbon filament bulbs where oxygen could react with the filament and cause it to burn out very quickly. In modern incandescent bulbs they use argon and other inert gases to prevent filament evaporation and also limit thermal conductivity, like a vacuum. Halogen bulbs are similar but they burn at a higher temperature and the trace halogen gases cause the evaporated metal to be redeposited on the filament.
So yes, a vacuum is used partly for its insulating purposes, but it’s not really the same as a thermos, window, or hypothetical refrigerator in that the heat source in a light bulb is in the vacuum itself, and it’s only there to protect that heat/light source. It’s not really used to insulate something else, or to block heat transfer that it isn’t itself creating.
The reasons for pulling a vacuum on a refrigeration system are:
[ol]
[li]Boil the moisture out[/li][li]Check for leaks[/li][/ol]
Yes exactly and also to remove air from the system.
I few years ago at CES, I saw a refrigerator that did have a vacuum seal. When the door was closed it reduced the air level inside to keep food fresh longer.
Does electrical insulation count?
The most common household vacuums are probably vacuum fluorescent displays though they are probably way behind LED and liquid crystal now. For example, my microwave display is VFD. CRTs are under vacuum but few televisions and monitors use them.
We call them vacuum tubes over here. Some radio equipment use tubes, too. Also, vacuum capacitors are used for some high voltage applications.
That sounds like marketing spin. There was (is?) a tabletop clothes dryer that purported to do the same kind of thing, using a partial vacuum to make clothes dry faster. However, to get any appreciably useful vacuum, you need a pretty hefty pump that’s loud and bulky and requires a decent bit of power, not to mention a LONG time to actually pull down that vacuum.
Yep. I have a Yeti beer coozy. If I pass out with a beer open, it’ll still be cold the next day. Flat, but cold.
There’s a very simple equation called the Ideal Gas Law that completely describes gases. No gas is truly ideal, but most of them that you’d encounter on a daily basis are a very good approximation to ideal. There’s nothing in the Ideal Gas Law that would hinder vertical motion of gases, so a gas mixture that really did somehow hinder vertical motion would have to be very non-ideal.
Many consumer products are manufactured using vacuum technology.
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Semiconductors : All electronic devices including the one you are reading this on relies on processors / semiconductors that need cutting edge vacuum technology. The vacuum needed for processors relies on cryogenic technology to create ever stronger vacuums. Vacuum technology is the enabler for more circuits on a processors.
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Food : from milk powder toy freeze dried products rely on vacuum.
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Perfumes : relies on vacuum to extract the aromatic compounds where heating will distort them.
Vacuum distillation is also used for petroleum refining and uranium extraction.
Yes, but none of those has a vacuum when it’s used, just as a part of making it.