Phiber said:
Really. This is why they use a 'condenser' to cool the air in for your air conditioner. Every air can I have ever used blew cold air.
that cold air from a can of compressed air, is rapidly decompressing... that's what makes it cold. the can is losing pressure.. and that's why it cools off.
Phiber said:
Get a pressure hose; small tip large tip. You blow it on your hand: the large tip will produce a less 'cool' feeling. The small one will produce a 'cooler' feeling.
You can even do it with your mouth in a couple of ways. Trap air in your mouth and blow as hard as you can with your mouth closed. Do this for about 30 seconds and then let go; condensation will come from your mouth. Why? Because it is cooler than the surrounding air.
the reason you feel the air as being cooler when you exhale with puckered lips is becuase of decompression. when you pucker your lips you are doing 2 things.
1. creating more back-pressure (compression) by making a point of restriction with your lips. thus causing the air in your mouth to be under higher pressure.
2. the air coming from your lips is decompressing, like the can of air, and thus cool......
Think about Detonation in your cylinders. you know, where the air/fuel combusts before the spark plugs ignite. this happens because the mixture heats under the compression and ignites. Octane levels are essentially a measure of heat tolerances, describing when it will combust under compression.....