Uniformity Of The Spray Irrigation Project Planning And Design Of Computer-aided Design System,

Sprinkler uniformity (CU) is an important technical parameter in the design of sprinkler irrigation. Nonuniform sprinkler irrigation induces that not only the crop growing will be affected, but also the limited water resources will be wasted. On the other hand, engineering investment increase with sprinkler uniformity. In practical application, pursuing the highest uniformity consequentially leads that energy sources will be squandered and engineering cost will increase sharply. Thus it can be seen that the effects of uniformity on sprinkler quality and investment are very important.The calculational methods of the sprinkler uniformity are the mostly investigative target in this paper. Because of the result's poor reappearance of the experimentation ,a new method is brought forward: sprinkler uniformity can be worked out with the using of the rainfall distribution information, plane interpolation method and superposition principle based on different combined spacing and arrangement form. Discussing the relationship among sprinkler uniformity, crop yield and project investment, this paper includes when sprinkler uniformity equals to 75% or less, the soil moisture content uniformity coefficient (CUs) is still high(95%). The relationship between crop yield and the spatial distribution of soil water content can conclude that the effects of decreasing sprinkler uniformity on crop yield are not remarkably, but engineering investment can fall sharply. So considering investment and output, this paper proposes to minish sprinkler uniformity in selecting design uniformity.With the use of Microsoft Visual Basic 6.0, a computer-aided design system of sprinkler irrigation aiming at uniformity is developed in this paper. Provided with a good man-machine conversation mechanism, this system can assist the user to finish the layout of pipe system, the establishment of the irrigation program, the calculation of sprinkler uniformity, the hydraulic calculation of pipe system, the selection of pumpmodels, the output of results, the calculation of benefit and economic analysis, and so on in the planning of sprinkler irrigation in plane area. The subsystem-calculation of sprinkler uniformity is the emphases in this system. It can automatically output sprinkler uniformity correspondent to different combined spacing and arrangement form with the elementary information of the sprinkler. This subsystem is demonstrated to have high accuracy and preferable practicability by the running results of calculating the sprinkler of ZY-2 while combined spacing is 18meter. At the end of the paper, a permanent sprinkler system programming in Aiyuan village, Siyang city is designed using the computer-aided design system of sprinkler irrigation aiming at uniformity, the running results showed that the man-machine interface is friendly, operating is simple, and the initial purposes are achieved effectively.