Some field experimental results have shown that the moving sands or dust aerosols in nature are usually electrified,and those charged particles also produce a strong electric field in air, which is named as wind-blown...Some field experimental results have shown that the moving sands or dust aerosols in nature are usually electrified,and those charged particles also produce a strong electric field in air, which is named as wind-blown sand electric field.Some scholars have pointed out that the net charge on the particle significantly enhances its electromagnetic(EM) extinction properties, but up to now, there is no conclusive research on the effect of the environmental electric field. Based on the extended Mie theory, the effect of the electric field in a sandstorm on the EM attenuation properties of the charged larger dust particle is studied. The numerical results indicate that the environmental electric field also has a great influence on the particle's optical properties, and the stronger the electric field, the bigger the effect. In addition, the charged angle, the charge density, and the particle radius all have a specific impact on the charged particle's optical properties.展开更多
The measured data in the wind-tunnel tests show that the wind-blown sand particles acquired a negative charge when their diameters are smaller than 250 μm and positive charge when their diameters are larger than 500 ...The measured data in the wind-tunnel tests show that the wind-blown sand particles acquired a negative charge when their diameters are smaller than 250 μm and positive charge when their diameters are larger than 500 μm, which confirms Latham’s assumption that the large particles in wind-blown sand flux acquired positive charge while negative charge developed on small ones. In the meanwhile, the measured data also show that the average charge-to-mass ratio for wind-blown sand particles decreases with the increase of the particle diameter and the wind velocity, and increases with the rise of height. The electric field in wind-blown sand flux is mainly formed by the moving charged sand particles. Its direction is vertical to the Earth’s surface and upward, which is opposite to that of the fair-weather field. The electric field increases with wind velocity and height increasing. These experimental results will lay the foundation for developing the theoretical analysis of the electrification phenomenon in展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.11562017 and 11302111)the CAS "Light of West China" Program(Grant No.XAB2017AW03)the Major Innovation Projects for Building First-class Universities in China’s Western Region(Grant No.ZKZD2017006)
文摘Some field experimental results have shown that the moving sands or dust aerosols in nature are usually electrified,and those charged particles also produce a strong electric field in air, which is named as wind-blown sand electric field.Some scholars have pointed out that the net charge on the particle significantly enhances its electromagnetic(EM) extinction properties, but up to now, there is no conclusive research on the effect of the environmental electric field. Based on the extended Mie theory, the effect of the electric field in a sandstorm on the EM attenuation properties of the charged larger dust particle is studied. The numerical results indicate that the environmental electric field also has a great influence on the particle's optical properties, and the stronger the electric field, the bigger the effect. In addition, the charged angle, the charge density, and the particle radius all have a specific impact on the charged particle's optical properties.
基金the National Outstanding Youth Fund (Grant No. 19725207) and the Natural Science Fund of Gansu Province.
文摘The measured data in the wind-tunnel tests show that the wind-blown sand particles acquired a negative charge when their diameters are smaller than 250 μm and positive charge when their diameters are larger than 500 μm, which confirms Latham’s assumption that the large particles in wind-blown sand flux acquired positive charge while negative charge developed on small ones. In the meanwhile, the measured data also show that the average charge-to-mass ratio for wind-blown sand particles decreases with the increase of the particle diameter and the wind velocity, and increases with the rise of height. The electric field in wind-blown sand flux is mainly formed by the moving charged sand particles. Its direction is vertical to the Earth’s surface and upward, which is opposite to that of the fair-weather field. The electric field increases with wind velocity and height increasing. These experimental results will lay the foundation for developing the theoretical analysis of the electrification phenomenon in