Comment on This has been your weekend PSA
cordlesslamp@lemmy.today 4 months agoThere’s a cheap machine that dip the can in ice cold water and spin really fast. It cool the can down to <10°C in less than 10 minutes. I think it’ll work even better with your salt method.
Baku@aussie.zone 4 months ago
How does that work?
TheOakTree@lemm.ee 4 months ago
By spinning the can in ice water, it increases the rate of transfer of heat energy from the can (and its contents) to the ice water. It’s like how stirring the ice in a cup of not-cold water will melt the ice / cool the water faster.
At a molecular level, you would see an increase in the number of collisions between ice molecules and liquid molecules. The collisions must occur for heat transfer to happen, so more collisions = more cooling. It is also the same reason why a heatsink can draw more heat from a processor when a fan blows air over it (until the air is saturated with heat).
Pentel@lemm.ee 4 months ago
How can air get heat saturated? i followed you thus far but its not like humidity, you can always add more heat the question is if a faster flow decrease the time for each molecule to absorb the heat/motion and thats why sometimes higher flow wont yield in better cooling
TheOakTree@lemm.ee 4 months ago
Sorry, saturation is not the right word to describe it. I was thinking of the ice/water analogy and I mistakenly applied it to my heatsink analogy.
The correct limit to the heatsink analogy would a function of the thermal dissipation of the heatsink (material, surface area, thermal resistance) and the qualities of the surrounding fluid (ambient temp, flow, etc). Honestly, my comparison between the ice/water example and heatsinks is not good. It is only appropriate in reference to the “molecular collisions” concept I mentioned before.
SpaceCadet@feddit.nl 4 months ago
When the temperature of the air and temperature of the object you want to cool reach an equilibrium, no heat gets transfered anymore.
Baku@aussie.zone 4 months ago
Thanks for the answer! That’s pretty cool honestly! Could you achieve the same result with anything that spins, like a lettuce spinner?
Schmeckinger@lemmy.world 4 months ago
You just need a way to spin the can. Probably works better if you speed it up and slow it down or reverse direction.
TheOakTree@lemm.ee 4 months ago
The main reason spinning a can works is because it induces convection inside and outside of the can, which contributes to more collisions and better distributions of collisions. If the warmest soda is in the middle of the can, the cold molecules near the can walls will reach a temperature similar to the ice bath and thud the rate at which heat is transferred becomes stunted.
For lettuce, you’d have better luck finding a way to pass cold water between the leaves, much like having fins on a heatsink (surface area).
TurtleJoe@lemmy.world 4 months ago
Just use your hand. If the beer is in a bottle, leave it so the neck is sticking out of the ice water and spin it that way (this also works very well for wine.) If it’s a can, stick it in vertically, and spin it for 30 seconds at a time or whatever you can stand.
Even if you aren’t constantly spinning it, it will still get cold much faster than any other method. I’ve worked in bars and restaurants for 15 years, and this is my go to, in case of emergency method for chilling beverages.
cordlesslamp@lemmy.today 4 months ago
Neat explanation, thanks.
cordlesslamp@lemmy.today 4 months ago
Something like this
youtu.be/6WqZdMLkdCI
I think you can get it as cheap as $10-$15.