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本文是叙述确定风对固定式、单喷咀、远射程喷头水量分布图影响的一项研究。风对灌水均匀度的影响是根据有风时的水量分布图与计算的无风时水量分布图的比较来决定的。实测的水量分布图与无风时水量分布图的偏差,随着风速的增加而增大。若是同一种喷头在田间沿行道移动,则水量分布常用固定的水量分布图来进行计算。计算出移动喷头的水量分布后,按不同的移动间距进行组合,並确定每个移动间距的克里斯琴逊均匀系数值。推导了一个回归方秤,用以计算均匀系数为0.85的最大移动间距,此间距为情条件风和喷头压力的函数。风速和喷头弯管处的压力都影响水量分布。对移动式喷头,影响水量分布的,还有风向与移动方向相互关系,当风向比较接近移动方向时,移动间距应缩小,以保持满意的水量分布均匀度。
This article describes a study that determines the effect of wind on the water distribution of fixed, single-jet, long-range nozzles. The effect of wind on the uniformity of irrigation is determined by comparing the water volume distribution when windy and the calculated water distribution without wind. The deviation of the measured water distribution from that of the no-wind water distribution increases as the wind speed increases. If the same nozzle in the field along the road to move, the water distribution is often used to calculate the fixed water distribution. After calculating the water distribution of the moving sprinklers, we can combine them according to different moving distances and determine the value of the Kronell’s uniform coefficient for each moving distance. A regression scale was derived to calculate the maximum moving distance with a uniform coefficient of 0.85 as a function of the condition wind and head pressure. Wind speed and nozzle pressure at the bend all affect the water distribution. The mobile nozzle, the impact of water distribution, as well as the direction of the wind and the direction of movement, when the wind direction is closer to the moving direction, the moving distance should be reduced in order to maintain a satisfactory water distribution uniformity.