Transformation of hydrological effect in Pisha sandstone area

摘要

The characteristics of raindrops in ordos city of Yellow River, including the speed and size of rainfall raindrops, they were analyzed through a natural rainfall on the sandstone slope of Pisa. The analysis results show that this time process of natural rainfall is very parabolic. We can see that with the increase of rainfall rainfall intensity, the count amount, size and terminal velocity of natural rainfall will increase greatly. In addition, the size and final velocity of natural raindrops are very scattered. In the process of rainfall, the final velocity is mainly concentrated in the range of 1.4-4.2m/s, and the peak of the rainfall final velocity is generally 2.2-3.4m/s. The rainfall mainly consists of 0. 125-1. 25mm raindrops. We can see also the final velocity of raindrops with a diameter of 0. 125mm was mainly between 1 and 1.4m/s, the final velocity of raindrops with a diameter of 0.25mm was mainly between 1.4 and 1.8m/s, the raindrop with a diameter of 0.375mm was mainly between 1.4 and 2. 2m/s, and the raindrop with a diameter of 0.5mm was mainly between 1.8 and 3.4 m/s.