Characteristics of Sand-blown Flow over Simulated Gobi Surfaces
Updatetime:2012-10-24From:
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The goal of this research is to reveal the characteristics of sand-blown flow over Gobi surfaces based on wind tunnel simulation experiments. Results are shown as follows. Aerodynamic roughness increases with increase of wind speed on simulated gravel Gobi surface, but deceases with increase of wind speed on simulated pebble Gobi surface. Wind speed varies logarithmically with height over simulated Gobi surface. The weaken effect of simulated gravel Gobi surface on wind speed is more obvious than that on simulated pebble Gobi surface. Sand transportation over simulated Gobi surface does not follow the exponential decreasing law with the increase of height as over mobile sand surface because the bounced angle of sand grain will increase when it collides with gravel on Gobi surface, and appears an inflexion and takes on "trunk-shaped". Sand transportation rate presents a power-functioned correlation with wind speed, but its power exponent is far greater than that on mobile sand surface. The value of the power exponent mainly depends on particle size composition of underlying surface.
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