If you want to see the better snowmaker project, check out my Snowmaker Mark II. This post is about my first attempt at making snow in high school.
My Mark I Snow Machine was simply a garden hose and an air compressor running compressed air directly past a small trickle of water. The resulting spray is a very fine mist of water droplets that can freeze/crystalize before landing on the ground. This is very important. The water must freeze before hitting the ground otherwise you will end up with the results of freezing rain, not what we are going for.
Some Extra Details
This is called a nucleation nozzle. In normal heavy duty snowmaking, there is/are on or a few nucleation nozzle(s) to provide a crystal structure for the larger volume producing water droplets to adhere to and crystalize onto.
The Science Behind Snowmaking
If you remember your chemistry classes, you might recall the equation PV = nRT. Let’s take out the constants (n, R, and the Unit Volume of air), and you are left with P = T.
Pressure = Temperature.
The varying pressure of the same unit volume of air effects the temperature of that air (similar to how your A/C unit works in your car or the condenser in your refrigerator).
The highly compressed air quickly escapes the nozzle and a large drop in pressure results as the unit volume of air is free to expand. As the pressure suddenly decreases, so too does the temperature. This phenomenon is the driving force behind freezing the nucleation droplets mentioned before.
The Results
After staying up until 2AM then waking up again at 5am to see the results before it melted (I wasn’t your average high school kid), I turned on the lights to see no more than a quarter inch of snow, that when shoved together, was just enough to make a grassy snow path for me to drop-in on my snowboard from my make-shift ramp up to my makeshift rail. I remember doing this twice – just to say I did it.