Experimental Study On The Temporal And Spatial Variation Of Vertical Electric Field During Sandstorm

With the deepening of the study of sandstorm,the existence of electric field in dust storm has been widely recognized,and as a new research field,scholars have gradually paid attention to it.At present,the research of sandstorm electric field is mainly confined to the near surface.The cognition of the sandstorm electric field on high is still very vague.In order to find out the spatial evolution of vertical electric field in the dust storm,a series of field observation work was carried out in QLOA(Qingtu Lake Observation Array).Compared with other field observation experiments,the experimental characteristics of this paper are as follows: 1)Multi-factor measurement: In addition to measuring the electric field intensity,the three-dimensional wind speed,dust concentration and ambient temperature were also measured.And a comprehensive analysis on variety of factors was done.2)Real-time high-frequency measurement: In this paper,all the instruments used in the experiment were SPC(sand counting equipment)to ensure the synchronization of the experimental data.Three-dimensional wind speed and temperature measurement frequency reached 50 Hz,dust concentration and electric field strength measurement frequency reached 1Hz.3)Measurement height and high spatial resolution: The measurement experiment had raised the height to 30 m,the three-dimensional wind speed and the ambient temperature measurement height was 11,the PM10 concentration measurement height was 12,the vertical electric field strength measurement height was 24(the spatial resolution reached 1m),which provided a guarantee for studying the spatial distribution of vertical electric field strength and its association with the spatial distribution of wind speed and dust concentration.4)Measurement cycle length: The observation experiment lasted for about 3 months,and the observation of dust weather more than 20 fields,which made the experimental data more comprehensive and improved the reliability of the experimental results.Through the research and analysis of the experimental results,the main conclusions of this paper are as follows: 1)It is proved that the stratified phenomenon of the vertical electric field exists in the dust storm does,the height profile and two obvious critical height of a change in two-direction were given,and found that the rise and fall of the layered structure still exists,but the intensity is less than the stable period.2)The vertical electric field and dust concentration were compared and found that the vertical electric field stratification phenomenon may be caused by the stratification of the spatial variation of dust concentration.3)The vertical electric field was compared with the wind speed and temperature,indicating that the wind speed in the range of 0.3m / s ~ 0.35 m / s,the vertical electric field size is mainly dominated by the dust particle size ratio.0.2m / s ~ 0.3m / s and 0.35 m / s ~ 0.5m / s range is mainly dominated by dust concentration.The effect of atmospheric temperature on the vertical electric field at different heights is consistent,that is,with the increase of temperature,the vertical electric field intensity increases.