沙粒形状的不规则性及静电力对起动风速的影响

Effect of Irregular Sand Grains and Electrostatic Force on Threshold Wind Speed

沙粒形状的不规则性使得沙粒的质心存在着偏心距,且沙粒所处位置的不同使其偏心角各异。笔者通过理论分析给出了起动风速与沙粒的粒径、偏心距、偏心角以及静电力之间的关系模型,并通过数值模拟研究了偏心距、偏心角以及静电力对起沙风速的影响。结果表明在风沙流形成的强电场中,沙粒偏心距为直径的0 05倍时与实验测量结果吻合得很好。

The shape irregularity of sand grains leads to eccentric distances in grains, and their variant positions when they begin to move results in the diversity of eccentric angle. Through theoretical analyses, this paper has given the model that relates threshold wind speed to diameter of grains, eccentric distance, eccentric angle as well as electrostatic force. Then, we numerically simulated the effect of eccentric distance, eccentric angle and electrostatic force on threshold wind speed. The results indicate that when the eccentric distance is equal to 0\^05 times of the grains diameter, the simulating results are coincident with the experimental results well.