Item: Controlling crystal habit in a small scale snowmaker
Title: Controlling crystal habit in a small scale snowmaker
Proceedings: International Snow Science Workshop, Davos 2009, Proceedings
Authors: Josephine Bones, E.E. Adams Department of Civil Engineering, Montana State University, Bozeman, MT USA
Abstract: The crystal habit, plates or columns, in snow crystals is dependent on atmospheric temperature. The secondary feature of the crystal, plates versus dendrites and columns versus needles, depends on the degree of supersaturation of the air. In the Montana State University’s Subzero Science and Engineering Research Facility specific snow crystals were grown by varying the temperature and supersaturation of the air in a controlled environment. A humidifier was engineered to generate a water vapor source. Air at the controlled temperature was directed across the humidifier at a low velocity using cross flow fans. The water vapor was transported into a chimney where hemp strings served as nuclei for crystal growth. Dendrites, plates, columns and needles were successfully created along with a byproduct of rime. The occurrence of rime appeared to be dependent on the transport wind velocity and rate of humidification. Addressing the occurrence of rime and purifying the crystal habits should be further researched. The significance of this project’s success in growing distinct crystal habits provides a potential avenue for a low-cost, small scale snowmaking system providing opportunities for other research.
Keywords: controlling crystal habit, growing snow crystals
Digital Abstract Not Available