On the Threshold Friction Velocity for Saltation of Sand
نویسندگان
چکیده
منابع مشابه
Saltation of Non-Spherical Sand Particles
Saltation is an important geological process and the primary source of atmospheric mineral dust aerosols. Unfortunately, no studies to date have been able to precisely reproduce the saltation process because of the simplified theoretical models used. For example, sand particles in most of the existing wind sand movement models are considered to be spherical, the effects of the sand shape on the...
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Results from a three-year study are presented that integrate field work (in Israel), physical modeling (wind-tunnel testing at UC Davis), and numerical solutions of grain trajectories to model and explain sand transport over a climbing dune. Field grain-size analyses of surfaceand saltation-trap materials taken along various positions of the slope suggest that only smaller particles (< 230 pm i...
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Stress waves contain useful information about the properties of porous materials; they can be recovered through different non-destructive testing methods such as crosswell, vertical seismic profile, borehole logging as well as sonic tests. In all these methods, it is crucial to assess the effects of frequency on wave attributes including velocity and intrinsic attenuation. The dependency of per...
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We show experimentally that the sliding friction on sand is greatly reduced by the addition of some-but not too much-water. The formation of capillary water bridges increases the shear modulus of the sand, which facilitates the sliding. Too much water, on the other hand, makes the capillary bridges coalesce, resulting in a decrease of the modulus; in this case, we observe that the friction coef...
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ژورنال
عنوان ژورنال: Papers in Meteorology and Geophysics
سال: 1969
ISSN: 0031-126X
DOI: 10.2467/mripapers1950.20.4_365