Scale model studies on snow drifting
Strom, Gordon H.; Kelly, George R.; Keitz, Edwin L.; Weiss, Robert F.
Research ReportSummary: Snow-drifting characteristics of various structures were studied by scale-model wind-tunnel experiments. Modeling criteria developed by two different methods were used as a basis for selecting a material for simulating snow in scale-model experiments and for determination of test variables. A number of materials were tested for physical properties which would make them suitable for snow simulators. It was found that, for a 1/10 model scale, 0.01 cm diam crystalline borax was the best available material. The work performed in the 3 and ½ by 7 ft wind tunnel adequately demonstrated the feasibility of using geometrically and physically scaled synthetic snow in a wind tunnel. It was also shown that it is possible to present several years of arctic snowstorm environment in a few hours of wind-tunnel time. The actual tests showed these major points: 1.) Close spacing of buildings will result in coalescence of drifts. This applies regardless of the orientation of the long axis of the building with respect to wind flow. 2.) When rectangular buildings must be grouped in closely spaced units, it appears that they should be erected with the long axis parallel to the dominant wind direction. Channeling the wind flow between paired buildings oriented with the wind tends to keep the space between the longitudinal rows of buildings open. 3.) Snow erosion may occur beneath buildings erected on columns above the surface. The columns must be carried to an unerodable stratum or they must be set on a crib foundation to prevent undermining of the footing. 4.) A V-shaped snow fence produced a clear area downwind for a distance equal to approximately 25 times the height of the fence. This phenomenon may be applied to the protection of trench entrances to undersnow structures. 5.) The tests with the borax snow simulator produced classic patterns of drifting very similar to those characteristic of cold dry arctic snow. 6.) The drift patterns produced by the unidirectional flow in the tunnel probably were more concentrated longitudinally than those developed under natural conditions where some variation in wind direction and speed occurs during and following periods of blowing and drifting snow.
U.S. Army Snow, Ice, and Permafrost Research Establishment.Engineer Research and Development Center (U.S.)
Snow; Snow mechanics; Snow drift; Snow fences; Snow models; Snow construction; Snowdrifts; EPOLAR
Research report (U.S. Army Snow
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