感应电机矢量控制系统的仿真研究

根据2008年4—7月黄山大气气溶胶观测资料,研究了气溶胶粒子的数浓度、谱分布特征及其与气象因子的关系,探讨了雾天和非雾天气溶胶颗粒物时间和尺度分布特点。分析发现,黄山光明顶春、夏季大气气溶胶数浓度的平均值分别为3.14×103个/cm3和1.80×103个/cm3,其中超细粒子（粒径小于0.1μm的粒子）在春夏季分别约占总粒子数浓度的79%和68%;高数浓度值集中在粒径0.04～0.12μm;积聚模态气溶胶粒子（0.1～1.0μm）在体积浓度分布和表面积分布中占很大比例。结合气象资料比较了雾天与非雾天气溶胶分布的差异,发现细粒子浓度非雾天大于雾天,而气溶胶数浓度与温度呈正相关,与相对湿度成反相关。结果还发现,黄山在春季以西北风和偏南风为主,西北风时气溶胶数浓度较高,在夏季主要以偏南风,特别是西南风为主,但是气溶胶数浓度的高值多发生在偏东风的条件下。

An Observational Study of the Microphysical Properties of Atmospheric Aerosol at Mt.Huang

Based on observational data of atmospheric aerosol from April to July 2008 at the top of Mt.Huang,the characteristics of aerosol particles such as number concentration,size distribution and its relationship with meteorological factors were analyzed and a comparison was made between cloudy/foggy and clear weather conditions.The results show that the mean number concentration reaches 3.14×103 cm-3 in spring,and 1.80×103 cm-3 in summer,respectively,and ultra fine particles（smaller than 0.1 μm in diameter） account for 79% and 68%,respectively,in the total number concentration in spring and summer.It is also shown that the size distribution of aerosol particles all appear as a single mode spectrum in spring and summer,with the peak value concentrating at particle sizes of 0.04—0.12 μm and that the accumulation mode particles（0.1—1.0 μm in diameter） dominate in the volume and surface distributions.It is found that the concentration of fine particles is higher under non-foggy weather conditions as compared with foggy periods and that particle concentration is positively correlated with the air temperature and negatively correlated with relative humidity.The results also show that while northwest and southerly winds dominate in spring,the particle concentration is highest when it is northwest.In summer,high particle concentration is observed when the wind blows from the east.