| Based on the rotational sprinkler during considering wind speed. A theory model was proposed for sprinkler range forest. Summarized the development and history of sprinkler, reviewed the development of sprinkler range calculated theory model. At last, the model calculated results was validated on sprinkler nozzle experiment. These show the model have a important role in sprinkler range calculation. The main research results as bellows:(1)Sprinkler range is one of the key indexes for sprinkler nozzle. There have many formulae to simulate and forecast the sprinkler nozzle range. But how to judging on the formulae is a key issue. The paper involved clustering analysis method to classifying five usual sprinkler nozzles. System Clustering Method is simply introduced. The classification is reasonable. The formulae are classified by their deviation from the experimental data and to be assessed based on their disadvantages and disadvantages. The comparison of five formulae can be classified three kinds with different levels. The formulae suggested by Cauazza and Feng Chuan-da and Yu Zhe-min are the best. This has a contribution to other field.(2)Sprinkler nozzle range is affected by many factors which interact with each other and are complex multi-variable and non-linearity systems. The artificial neural network can describe the indefinite multi-input and multi-output features of non-linearity model effectively. However, the training of artificial neural network is a complex problem by conventional back-propagation (BP) Optimal algorithm which has intrinsic weakness in slow convergence and local minimization. In this article, a prediction model for sprinkler nozzle range was developed by using Levengerg-Marquardt Optimal Algorithm, and the nonlinear relationships among sprinkler nozzle diameter, nozzle elevation and working pressure were established. On the base of these above, the relationships of nozzle range and factors were simulated. The experimental results calculated from MATLAB software show that this method is more effective and accurate than BP optimal algorithm, and it can be applied for prediction of sprinkler range.(3)Many semi-empirical and semi-theoretical formula were proposed to solve the nozzle rotational sprinkler range without the wind velocity. But in practically occasions, water-drop trajectories, velocities and range are altered by wind. Based on the Newton's Second Law and aerodynamics principle, a three-dimensional theoretical model for the irrigation sprinkler nozzle range was set up. The model took into account the wind velocity on the droplet travel. Then, the model was tested and consequently compared with field experiments and other authors'formulas results, obtaining a satisfactory agreement. The results showed a very good agreement for most cases. The average relative error is only 8%, greatly below other formula. It is applicable to all other kinds of sprinklers. This will supply a foundation for the further study in this direction.(4)Sprinkler droplet size distribution is one of the key indexes of the sprinkler nozzle performance. The traditional measurement methods, such as color spot method, are time consuming and troublesome. So it is very necessary to search a simple, fast and accurate method to measure sprinkler droplet size. This paper puts forward a measurement method based on Adobe technology. It magnifies the color spot with equal proportion, draws the edge of every color spot and measures the color spot area automatically. The spot areas are directly imported to Excel worksheet and transferred to the droplet diameter. The relationship is calculated between color spot and droplet diameter and the exponent equation is formed. Meanwhile, based on this method, he droplet size distribution of Rain Bird 30PSH, and 46H sprinkler nozzle were measured and droplet diameter D1 (mean droplet diameter), NMD (numeric medium diameter; the drop diameter which corresponds to 50% of the number of drops accumulated) and VMD (the volume medium diameter; the drop diameter which corresponds to 50% of water volume accumulated) was calculated. The correlation between droplet diameter and the distance to the nozzle was analyzed, and the droplet accumulated volume content curve is got. The results showed that the new measurement method can extend the lower limit of nozzle droplet measurement from 1mm to 0.2mm, realize the procedural droplet diameter measurement and conversion, enhance the accuracy and reduce the workload greatly.
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