前言由克里斯琴森(Christiansen)(1941)提出的均匀系数已普遍作为喷灌设计的准则,在一定的重叠图形下,支管和喷头的间距对它起主要作用。然而,在重叠图形情况下,也要求沿支管的压力变化保持在容许的范围之内,以便各个喷头流量的变化在一定的范围之内。在喷灌支管中的流动状态是稳定的並随空间变 Preface The uniform coefficient proposed by Christiansen (1941) has generally been used as a guideline for sprinkler irrigation, and the spacing of branch pipes and sprinklers plays a major role in certain overlapping patterns. However, in the case of overlapping patterns, it is also required that the pressure variation along the branch pipe should be kept within the allowable range so that the variation of the flow rate of each nozzle is within a certain range. The flow in the sprinkler branch is stable and varies with space