The Research Of Sprinkler Irrigation Uniformity Coefficient Calculation Methods

Sprinkler irrigation is an advanced water-saving irrigation techniques, it has been promoted worldwide.Sprinkler uniformity, which refers to the degree of uniformity in water distribution within the irrigationarea, is an important indicator of hydraulic performance and irrigation quality for sprinkler irrigationsystems. The uniformity coefficient calculation for multiple sprinkler combinations can result in differentresults depending on the calculation method used. To investigate the effects of catch-can spacing,sampling-grid spacing, and interpolation methods on the Christiansen uniformity coefficient (Cu),6different sprinklers were used as research subjects in this paper. The author calculated the Cuwith1or2msampling intervals and1or0.5m grid intervals using linear interpolation, cubic interpolation, cubic splineinterpolation, the inverse distance weighting method, and the plane interpolation method. The main resultsare as follows:(1) At present, when scholars studied the sprinkler performance and evaluated the irrigation systemquality, they rarely pointed out the calculation method which they used, thus led to the quality evaluationstandard nozzle performance and sprinkler irrigation ambiguity.In order to improve understanding ofirrigation quality evaluation accuracy, this paper has compared the scientific criteria among differentcalculation methods and explored different methods for Cu calculation.(2) Studied five interpolation methods which were commonly used to calculated Cuand established theirinterpolation models which included linear interpolation, cubic interpolation, cubic spline interpolation, theinverse distance weighting method, and the plane interpolation method.(3) Test three single Nelson R33, GJYA-2and FY RB-471sprinklers indoor under zero windconditions and test three single ZY-1, ZY-2and30IBH sprinkler outdoor with wind conditions to obtainedwater distribution data and drew the radial water distribution curves of each nozzle, also analyzed thecharacteristics of nozzle radially water distribution.(4) Cus of six kinds of nozzles in different combination methods, different combination spacing, usingdifferent calculation methods were calculated, and analyzed the change rules of Cuaffected by calculationmethods for each nozzle.(5) The paper applies the orthogonal and variance analysis methods to this experimental combinationto analyze various factor impacts on Cu calculation results. This is the first quantitative evaluation effort to understand the factors that impact irrigation Cu.