No point to this thread, just I bought a new product recently that is the exact opposite of a vacuum flask. For baby milk... the "Nuby Rapid Cool". It's a really heavy flask that looks just like a vacuum flask. You pour boiling water in and baby milk powder and it cools it down to drinking temp in a minute or two. Takes a few hours to "reset". Didn't believe it until I used it but it's absolutely perfect for it's purpose.
Just thought it was funny that something so opposite to a vacuum flask exists. How far mankind has come.
I keep wondering how it works and just assume there is some dense thermally conducting material lining the flask that sucks all the heat out of the milk inside. Took me back to my thermodynamics module at uni (which was far too complicated!)
