January 1, 2019.
In order to test different types of anti-icing fluids that are used on aircraft surfaces prior to take off, it is necessary to develop a machine that artificially generates snow. Deicing aircraft is a two-step process that consists of applying both deicing and anti-icing fluids. Deicing fluids are applied to eliminate accumulated ice on aircraft surfaces that could obstruct proper airflow. Anti-icing fluids are then applied to prevent the additional accumulation of frost, ice, and/or snow for a period of time known as the endurance time. The endurance time is the duration the anti-icing fluid remains effective on the aircraft surface. Results from the snow machine tests have shown that it accurately replicates natural snowfall, and allows for repeated, controlled-environment testing throughout the year. Variables controlled include wind speed, air temperature, and liquid-water equivalent snowfall (LWE) rates. The machine is also affordable and more efficient than outdoor testing. In order to continue studying the factors that influence endurance time and accumulation rates, the design of the existing snow machine has been modified to increase effectiveness and efficiency. Aluminum struts make up the framework of the snow machine which measures 2.75m tall with a base of 0.91m by 0.66m and are bolted at the midpoints for structural integrity. The sides are made of clear Plexiglass which slide into the frame rather than being attached from the outside with hinges. This eliminates excessive construction material and provides a better appearance. The top of the machine is cut into 45° angles to evenly fit and level the pieces of struts, whereas, the previous model had overlapping struts that formed gaps between overlaid pieces of the frame. Finally, wheels were added for easy transport. These modifications, along with software improvements are targeted for additional testing in the near future.
National Center for Atmospheric Research (NCAR)
The 2018 STEM Teacher and Researcher Program and this project have been made possible through support from Chevron (www.chevron.com), the National Marine Sanctuary Foundation (www.marinesanctuary.org), the National Science Foundation through the Robert Noyce Program under Grant #1836335 and 1340110, the California State University Office of the Chancellor, and California Polytechnic State University in partnership with National Center for Atmospheric Research. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the funders.