Air permeability of snow
Bender, James A. (James Arthur), 1923-
Research ReportSummary: Laboratory experiments on the air permeability of various screened and natural snows are described, and, results are analyzed to determine whether the parameters obtained from the measurements could be used to define a snow type. The permeability of a snow sample of known porosity (calculated from density) was determined over a wide range of air velocities; the sample was then compacted artificially a few mm, its density was determined, and its permeability measured again. The procedure was used to obtain curves for several densities of the same sample. Air flow appeared laminar for velocities less than 5 cm/sec in fine-grained snow (less than 0.8 mm in diam.), 2 cm/sec in medium-grained snow (0.8-1.2 mm diam.), and 1 cm/sec in larger-grained snow. A formula is presented expressing all of the results obtained under laminar-flow conditions in a single relationship, and an equation for estimating grain size from initial permeability and initial porosity is suggested. Snow conversion tables and a discussion of the effect of varying sample porosity on its permeability are appended.
U.S. Army Snow, Ice, and Permafrost Research Establishment.Engineer Research and Development Center (U.S.)
Snow; Snow permeability; Air flow; Air permeability; Environmental engineering; Eutrophication; Porosity; Snow density
Research report (U.S. Army Snow
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