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gerrman97
January 21st, 2013, 04:44 AM
Hey everbody,
So today me and my little sibling were having a discussion about how to keep ice cold in an average room tempurature control environment. Sibling : you put it in a cardboard box and put styrofoam around it and seal it off.
Me: take the cube, put a single layer of aliminum foil completely around it while standing in the coldest areas of the house, then take a thin copper tube and shape it to where it stays sturdy but not to tight around the cube. Put extremely cold water into the tube and seal it off. Then take a medium sized, average speed desktop computer processor fan and point it directly above the cube. And turn it on, obviously. Whos right (in your opinion) 1 for sibling, 2 for me. Just post the number and why below. (btw, i have years of experiance adding extra sources of cooling to computers, my sibling has the knowledge of a single expirement that she did in elementary school)
gerrman out.

gerowen
January 21st, 2013, 04:53 AM
Just putting styrofoam around it would be easier and less time consuming than rigging up copper tubing, a CPU fan and everything else. Of course your method would work better for preserving a block of ice, you obviously know that. I guess it depends on how long you expect the ice to last and how often you plan on replacing it.

EnigmaticCoder
January 21st, 2013, 06:21 AM
I wonder if these things would also work for keeping something cold.

http://www.joulies.com/#

Actually they would probably make it room temperature quicker.

alphacrucis2
January 21st, 2013, 07:17 AM
Hey everbody,
So today me and my little sibling were having a discussion about how to keep ice cold in an average room tempurature control environment. Sibling : you put it in a cardboard box and put styrofoam around it and seal it off.
Me: take the cube, put a single layer of aliminum foil completely around it while standing in the coldest areas of the house, then take a thin copper tube and shape it to where it stays sturdy but not to tight around the cube. Put extremely cold water into the tube and seal it off. Then take a medium sized, average speed desktop computer processor fan and point it directly above the cube. And turn it on, obviously. Whos right (in your opinion) 1 for sibling, 2 for me. Just post the number and why below. (btw, i have years of experiance adding extra sources of cooling to computers, my sibling has the knowledge of a single expirement that she did in elementary school)
gerrman out.

Why not just put it in a freezer.

gerrman97
January 23rd, 2013, 09:10 PM
gerowen: i agree, but i am trying to prove to her that i know what im doing, and that shes wrong.
EnigmaticCoder: i am not looking for anything else. i simply need opinions. (nice username, btw)
alphacrucis2: thank you, but im just trying to figure out which way is better(more right than the other), so i can prove her wrong. if we just wanted it to stay cold, then your suggestion would help.
gerrman out.

Gremlinzzz
January 23rd, 2013, 09:41 PM
:popcorn:vote #1
me i would just move to a igloo:D

Paqman
January 23rd, 2013, 10:34 PM
Neither solution would keep the ice cool indefinitely.

To do so you need some way of removing the heat as it gets in. Air cooling isn't going to be effective, as you're using room temperature air (ie: it can't cool anything below room temp) and the insulation won't be effective, because eventually the heat will get in.

The most simple way of moving heat out of a cold place and into a warmer place is a heat pump (ie: refrigeration). If that's not an option then I would go for a vacuum flask and a heroic amount of insulation for good measure.

Or you could cheat and interpret the challenge more liberally. You said "average room temperature", you could interpret that as being the average temperature of the universe which is about 3 K IIRC. Shouldn't need anything much to keep ice solid at that temperature...

CharlesA
January 23rd, 2013, 10:36 PM
:popcorn:vote #1
me i would just move to a igloo:D

This.

Number 1 has the easier and more convenient solution.

ssam
January 24th, 2013, 05:55 PM
keeping something cold is very different from cooling something that generates heat.

blowing something with a fan just helps it move towards the ambient temperature. this is a good way to cool something that is hotter than the ambient air.

insulating something (eg with styrofoam) reduces the heat transfer. if you insulated a CPU it would bake, because it generates heat that would not be able to escape. insulating an ice cube will stop the heat from the air getting in.

its possible that you might get some evaporative cooling if you are blowing something wet (this is why fans are good for cooling people). but it sounded like you sealed all the water in the pipe.

as you mention science, i recommend that you do an experiment. :-)

grahammechanical
January 24th, 2013, 06:18 PM
With option 2 the ice will cool the water in the tube, not the other way around. The water in the tube needs to be colder that the ice cube.

Years before refrigerators and freezers were invented people kept things cold by putting ice in rooms/stores that were thickly insulated with cork. The ice brought the store room temperature down to a point where food could be preserved.

How do you keep food hot without a source of heat? How do they transport an body organ from a donor to a recipient for transplanting? Think Cool Bags. It is all the same scientific principle.

Sorry.

gerrman97
January 30th, 2013, 08:31 PM
thanks all. very helpful, yet, i am sorry that most thought i was wrong. ehh, whatever. doesnt matter. i cannot change what i have previously said as the idea. it was a bet, and i lost.