Don't believe it
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I saw a clip on the news last night where in the US, to demonstrate it's getting pretty chilly, they threw some boiling water in the air only to have it fall to earth as snow. Like a scene out of the dismal 'Day after tomorrow'. Really? So it's going to drop 100c in a second and also dissipate it's latent heat to solidify in the space of a second flat in air - a very good heat insulator? I'm having a very hard time accepting this. What says the CodeProject community?
Regards, Rob Philpott.
Some food for thought: It takes 1 calorie to lower 1 gram of water 1 degree C. But it takes 80 calories to turn 1 gram of 0C water to ice (which is why ice cools liquids so well) Roughly, it is taking more energy to cool the water to freezing, if it is truly boiling. Regardless, air is not a great conductor, but cold air, with a high wind chill, can SIMULTANEOUSLY steal some of the moisture, like it does to chap your lips, and quickly lower the water temperature. Keeping in mind, that man-made snow is made by spraying WATER into the air and having it fall as snow, means this is quite possible at freezing temperatures. At temperatures SIGNIFICANTLY BELOW freezing, I would assume hotter water could certainly be used. Oh, and the wives tail about putting HOT water in the Freezer to make ice cubes faster comes to mind. THE ONLY WAY it could work, is that it forces the thermostat inside the freezer to register a higher temperature, and to kick in MUCH MORE COOLING in the same period of time. This of course, assumes you test this in the same freezer on 2 separate runs. In effect, you are revving the engine of the freezer because of putting hot water in it. (again not boiling water, but the key thing is that 80 calories to freeze is larger than the temperature to cool of hot water, it becomes part of the limiting factor). Admittedly, if both trays were put in at the same time, the cooler water should certainly freeze faster.