How Snow Guns Keep the Slopes Coated in Fresh Powder


qq_snowblower_numbers

Bryan Christie Design



Between muddy trails and shorter seasons, global warming puts a chill on ski resorts. Typically the solution is one beloved by cold-themed supervillains everywhere: snow guns! Such blowers used to be expensive to run, but new versions, like Snow Logic’s DV4, expectorate winter wonderlands more efficiently. The upshot for one Vermont resort this season: $235,000 in projected savings, a 2.6 million-pound reduction in carbon emissions, and slopes full of happy, mogul-carving skiers.


qq_snowblower2_f

BRYAN CHRISTIE DESIGN



1. Water Nozzle


Water blasts out through a cruciform nozzle; the perpendicular planes disrupt each other, breaking the stream into lots of tiny droplets. That increases the liquid surface area exposed to the air and speeds up freezing.


2. Nucleator


Snowflakes can form at higher temperatures if they grow from a seed—a piece of dust, a grain of silver iodide, or in this case, an ice crystal. Compressed air shoots ice particles from the nucleator into the water spray, where H2O molecules freeze around them.


3. Settings


Resorts adjust the amount of water to make various kinds of snow: wet, dense lower layers or the dry, fluffy topcoats that skiers love to slice through. Some guns automatically tweak their water settings to account for humidity that’s already in the air.


4. Pressurized Air


As the compressed gas escapes, the drop in pressure causes a local plunge in air temperature (like how the air whooshing from your bike tire feels cold). That means water can crystallize even when the ambient temp is several degrees above freezing.


5. Compression


It takes energy to pressurize air and pipe it up the hill. But Snow Logic’s model expels just 8 cubic feet per minute instead of (in older snowmakers) 300 to 500 cfm, thanks to optimized channels in the nozzles.


Watch SnowLogic’s blowers in action.



No comments:

Post a Comment