blowing on hot food

[joel kehat]

Is there a sientific evidence that when a parnet blowing on hot food it really cools it out?

[Clanad]

Sure, we could talk about adiabatic cooling, for example. This term simply means that either compressing or expanding a given volume of air either heats it (under compression) or cools it (under expansion). As you blow across the hot food you purse your lips and the escaping air is first compressed (inside the lips) but then rapidly expanded,(just outside the lips) resulting in a lowered temperature. Additionally, the heat exchange that occurs when convection cooling occurs is partly responsible. Convection cooling is heat transfer in a gas by the circulation of currents from one region to another, such as from hot coffee to the cooler breath blowing across it. Numerous Laws of Physics are at work during the process...

[tigerthecat]

cool... answer :-)

[joel kehat]

Your answer is not the one I have expected. So I will re-phrase it. Was it ever measured by how much blowing the relatively hot air from the mount cools the food compared with simply waiting these 3-4 seconds?. Is there a scale of numbers containing the volume of food, the blowing time, etc.?

[Clanad]

Hmmm, appears to be a different question entirely and one for which I do not have a ready answer...

[Gef]

I doubt if there has been serious scientific study. However, it works. The "relatively hot air" in your mouth is still much cooler than hot food. Also, stirring and breaking up lumps helps the cooling process.