含水量对冰晶增长影响的风洞实验研究  

EXPERIMENTAL STUDIES ON THE INFLUENCE OF LIQUID WATER CONTENT ON THE GROWTH OF ICE CRYSTALS IN A VERTICAL WIND TUNNEL

作　　者：陶树旺[1] 龚乃虎[1] 

机构地区：[1]中国科学院兰州高原大气物理研究所,现在中国辐射防护研究院工作730000

出　　处：《气象学报》1992年第4期442-449,共8页Acta Meteorologica Sinica

基　　金：国家自然科学基金

摘　　要：用小型垂直过冷云风洞及其测试系统,使冰晶在自由悬浮的情况下生长。在实验温度为-5℃—15℃、含水量为0.5—2.0g/m^3的范围内,结果表明:在水面饱和条件下,冰晶的形状决定于所处的环境温度,含水量的大小对冰晶的基本形状没有影响,只是当含水量加大时,冰晶上会出现更加明显的碰冻增长的痕迹;冰晶的质量和速度增长的峰值和谷值温度分布与含水量的大小无关;随着含水量的增加,冰晶的质量和下落速度的增长会加快,但没有发现含水量的增加有加快冰晶2a轴增长的明显效果。lce crystals were grown at temperature ranging from -5℃ to -15℃ and liquid water content from 0.5g/m3 to 2.0g/m3. Observations of the habit, mass, falling velosity and 2a-axis of ice crystals were made, and the results of the experiments were as follows:1. The shapes of ice crystals grown in vapor saturated with respect to ice only depended on the supercooled fog temperature. Liquid water content did not affect the basic shape of ice crystals. However, the mark of catch of fog droplets was more obvious on the ice crystals when the liquid water content was larger.2. When the mass of ice crystals at given time and liquid water content was measured as a function of temperature, there was a main peak near -14℃, a secondary peak around -10℃, and a smaller peak was located at around -6℃, Mass minima were at around -7℃ and -11℃. The extreme value points didn't move with liquid water content. However, the mass growth rate was larger if liquid water content was larger. It was the effect that the ice crystal caught supercooled fog droplets.3. There was a falling velosity maximum near -10℃, and a minimum near -14℃. The extreme value points of velosity didn't move with liquid water content either. The acceleration increased with liquid water content.4. The growth rate of length of 2a-axis was maximum at around -14℃. But it wasn't found that the growth rate of 2a-axis increased obviously with liquid water content.

关 键 词：含水量 冰晶 增长 风洞 

分 类 号：P426.63[天文地球—大气科学及气象学]