CHEMIGATION PIPELINE TRANSPORT MODEL FOR NONSOLUBLE PESTICIDE .2. NUMERICAL AND FIELD VALIDATION

A computer model describing the injection and transport of a nonsolubl e pesticide in a linear move irrigation lateral is developed and valid ated. Inputs to the model are both intensive and extensive properties of irrigation water and pesticide, and the model outputs chemical conc entration in water for each sprinkler along the linear move irrigation lateral. Numerical studies are performed that compare Eulerian and La grangian methods and provide the transition between the two methods. T he transport model and a model for evaluating drop diameter are used t o calculate sprinkler discharge concentration as a function of distanc e along the pipeline, and the model is compared with field data for a single port injector. The model is also evaluated for multiorifice and multiport injection systems. A technique for optimizing placement of injectors for the multiport system is described and evaluated.