Now i know from the heading you are all saying: “You want device that freezes something? try a freezer jackass” well that isnt good enough.
we have Ovens, and we have Microwave Ovens.
we need a Microwave Oven type Freezer. Would it be possible? expensive? because if they were made commercially available everyone would have one.
thats my AUS$0.04 <—not my joke, saw it here, credit goes to who said it first.
The best I can understand from your OP is that you want a freezer that’s small and fast. You pop in the object that you want to cool, press the “freeze” button and after a minute or so it’s deep-frozen. Is that it?
If so, the technology would be the same as for a conventional fridge or freezer, with an electric-pump driven absorption cooling cycle pumping heat out of the cavity and into the room. This can be as powerful (and deliver as much cooling effect) as you want, so yes, it can be done.
Another option is to have a flask of liquid nitrogen and dump the food (or whatever) into it for a few seconds. I used to do this with cans of coke, with mixed results.
Just curious. Liquid nitrogen is comercialy availible, or you work in a feild with access to it??
I’ve always wondered where to get some. I used to have a lot of fun with dry ice when i was a kid when my dad would bring it home for us. Liquid nitrogen just seems to be the next step in fun.
As for the OP, other than cooling beer or other drinks, what use would this have? I’m thinking there must be something(s), but not that my fizzling brain can come up with at this hour. I think there was something like this in weird earls at some point, but can’t fid the site. Anyone?
A mate of mines mum had a sort of wine cooler.
You but the bottle in a sealed unit and attached a cartage to it. When you pressed the button the gaseous contents of the cartage were emptied into the sealed unit and the bottle would be nicely chilled.
We used to put creatures, like ants and spiders, in the unit and then do it. Cruel I know but we were only kids.
One thing that is a little bit of a problem is that while a microwave can heat from the inside-out of a substance, I don’t know of anything that can cool from the inside-out. Thus, things that create fast cooling effects are going to have to deal with the thermal conductivity of the item being cooled, whereas a microwave heats the water molecules directly (which, in turn, heat the non-water molecules through conduction and convection, etc).
This was when I was a postgrad giving metallurgy labs. I used to play around (safely!) with the liquid N[sub]2[/sub] a lot, because the students liked it and were more scared of it than necessary. I don’t know how you would go about buying it, but if you know someone in a university physics department, they could help you out.
you could always supercool stuff with lasers.
http://www.colorado.edu/physics/2000/bec/
Have a look at the link for cooling stuff with lasers (this is a ‘cool’ simple website which explains some interesting physical stuff.
Nask
How would you keep this machine from freezing itself RAWisSYDNEY?
You might want to look at this guy’s solution to the problem. 
Sigh. Guess this is my day for hitting “submit” too fast…
Liquid nitrogen is readily available; try checking welding supply houses. You will have to pay a deposit on the dewar flask to carry it; your Igloo cooler won’t quite cut it. I’ve seen people use it to make instant ice cream.
Well, Sydney, the gadget you’re thinking about would be the kind of thing that the frozen food industry uses to flash-freeze things. They trundle them down a conveyor belt and spray them with liquid nitrogen. Poof! instant frozen lima beans, or french fries, or whatever.
And the reason that this technology is not widely available for the home (which is your question), is that working with liquid nitrogen can be incredibly dangerous. We’re talking about accidentally freezing off your own fingers in only a second or two. Ever watch one of those liquid nitrogen demos at the Science Place or the Children’s Museum? See the humongous heavy gloves the girl is wearing? That’s not just for show.
Even if you did figure out a way to stick your hand in a microwave and cook it, the worst you could get would be really, really bad burns, and it would take a long time to do it, by which time (presumably) you would have responded to your pain signals and removed your hand from the microwave.
But if you stick your hand in the liquid nitrogen Freez-O-Matic[sup]R[/sup], it’s like whoosh! and your suddenly brittle fingers fall off your hand. No time for regrets.
Are you talking about some kind of anti-microwave, that shoots out rays of ‘freeze energy’?
No gots.
In the april edition of an electronics magazine I used to get, they had an article on how to build a “Macrowave oven” which would supposedly do this. It was a joke, of course, and it turned out that you needed to use liquid nitrogen anyway because the (fictional) device which produced the freezeing macrowave rays was superconducting.
Aw, dang! I wanted to be Mr. Freeze. Could you work on that?
I’ve got this knife in the kitchen, take a finger off in less thana second methinks.
bought it in boots the other day.
the ylet me have it. not evena safety warning *
dont think their’d be a problem with CO2( ? ). well their might. but just thought i’d point out that they let some crayzee stuff in kitchens!.
a sealed unit that only works wehn its closed would be pretty safe ( microwave style )
Sorry, Anthracite, but that’s a UL that needs to be put to bed. Microwave ovens do not heat stuff from the inside-out. As you mentioned in the rest of your post, microwaves heat by exciting the water molecules in food. Since this means that water is opaque to microwaves, the energy cannot slip by the outermost water molecules to heat those at the center of your meal.
You can try this yourself. Put a frozen dinner in your microwave and heat it for half of the required time. The outside will be thawed, while the center will still be frozen.
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As for the OP, other than cooling beer or other drinks, what use would this have? **
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What other use would it need? I have wished for such a device myself many times.
Well, I’m sorry too, but I’m correct in what I said. You’re assuming that the outside of the substance is always opaque to the microwave. Put a bottle of water in the microwave, or a coffee cup, and see what happens. It doesn’t heat the water by heating the glass up, then transferring the heat by conduction or free convection to the water. It heats from the inside-out, and the glass heats up from the water.
The point is that in conventional heat transfer (conduction, convection, and radiation) the initial transfer of heat is through surface effects. The direct conduction of the molecules, convection of a fluid about the substance, or radiation absorbtion on the surface. The microwave induces the molecules to heat themseleves, so to speak, and thus it can heat from the inside out. Does it do the best job at this, or does it heat entirely from the inside out? No, and not only did I not say that, I didn’t imply it. I’m trying to make a distinction between stuff that is a bulk surface effect, versus something that is not.
That’s the joke article I was talking about. It wasn’t a klystron tube, it was asomething made-up - a “Kryostron” tube or something like that. And they also stated at the end of the article that the “macrowave oven” would have to be submerged in liquid nitrogetn in order to function.