'Tis the season for snow! A few days ago, we brought you the story of Dr. Ken Libbrecht, the snowflake expert responsible for the flakes on Disney's Frozen and on postage stamps. We also told you about Nathan Myhrvold, a former CTO at Microsoft and the founder of Modernist Cuisine, an innovative food lab, who built a specific camera and lens to capture snowflakes in their glory.
However, lately, climate change has decreased the chances of having snow for the holidays in some parts of the world. What are Christmas and new year's festivities without a little snow? Harboring this in mind, Sean Hodgins, YouTuber and founder of Idle Hands Development, came up with a solution that lets you capture the magic and mirth of winter from your bedroom with a snow globe that generates its own. How cool is that!
Snow globes, though available around the year, make an anticipated appearance by December. The tacky souvenirs enclose a small 3D vignette or character inside a glass sphere filled with water and tiny white particles that swirl around when shaken, creating an artificial flurry effect.
Though the Web is full of nifty project ideas for making your snow globe, Hodgins wanted something more authentic, so he scavenged a power supply, cooling fan, heatsinks, and a PC’s CPU cooler for the core of this build.
Up to 'snow' good
He milled a tiny snowman from aluminum to give the snow someplace to grow, while a pair of two-watt resistors were added to create vaporized water particles, which would be the key ingredient of the supposed snow. But Hodgins still faced a dilemma: Heatsinks and fans can help prevent a CPU from over-heating, they don’t remove enough heat to create freezing temperatures which are another key ingredient for making snow.
To recreate a winter wonderland in a globe, Hodgins added a series of stacked thermoelectric coolers that use the Peltier effect to create a temperature difference between two different materials when an electric current is applied. One side gets warm while the other gets cold, and by stacking several of the coolers together, a temperature difference of 140°F (60°C) was created, which was more than sufficient to cause the water vapor in the globe to condense and freeze on the aluminum snowman, draping it in snow. Check out the process in the video below.
Watching the snowfall is a near effect, but creating the required temperature differences using the thermoelectric coolers draws a lot of power, according to Gizmodo.
With a little bit of creativity and some engineering knowledge, it's possible to make it snow. At least on a snow globe scale.