Change of size distribution of snowflakes caused by melting-disintegration process

作者测量了雪花在煤油中融化所形成的水滴的粒径分布。水滴的数量随着雪花质量的增加几乎呈线性增加。由于水滴的数量随着雪花质量的增加而增加，水滴的平均尺寸随着雪花质量的增加而减小。水滴粒径分布的标准偏差随雪花质量的增加而减小，大的雪花倾向于形成相对较小的水滴，分裂成大量水滴的雪花具有较大的特征因子，即直径、质量、横截面积和粗糙度。然而，上面所写的具有大特征因子的雪花并不一定会分解成大量的水滴。粗糙度与横截面积、力矩与质量的相关性较差。这些结果表明，力矩和破碎程度不依赖于雪花的质量和大小。雪花的出现时刻和规则性与空气中冰晶的聚结过程密切相关。因此，冰晶随机聚结，聚结的方式与雪花的质量和大小无关。

The author measured size distributions of water droplets which were made by melting snowflakes in kerosene. The number of water droplets increases almost linearly with increasing the mass of snowflakes. As the number of water droplets incteases largely with increase in the mass of snowflakes, average size of water droplets decreases with increasing the mass of snowflakes. The stanbard deviation of the size distribution of water droplets decreases with increasing the mass of snowflakes, and the heavy snowflakes tend to make relatively small water droplets.The snowflakes which disintegrated into large number of water droplets have large characteristic factors, that is, diameter, mass, cross sectional area and the degree of ruggedness. However, the snowflakes with large characteristic factors written above did not necessarily disintegrate into large number of water droplets. The correlations between the degree of raggedness and cross sectional area, and moment and mass were poor. These results indicate that the moment and the degree of raggedness do not depend on the mass and size of snowflakes. The moment and the reggedness of snowflakes closely relate to coalescence process of ice crystals in the air. Therefore, ice crystals randomly coalesce and the way of coalescence does not depend on the mass and size of snowflakes.