In order to obtain good yields of crops, the supply of water and nutrients is essential to plants. A practice that makes the simultaneous application of water and nutrients or agricultural chemicals is called quimigation and its rational use, depends on complete knowledge of the hydraulic performance of the injection system. This study intended to evaluate the hydraulic performance of a injector pump of fertilizers (Indek) with the development and the calibration of a mathematical model to relate the operational conditions (tuning of the course of the pump’s pistols, injection and suction pressure) with injection of fertilizers in irrigation systems. Through trials in the laboratory, simulating field conditions, the values of final flow injected were obtained and a mathematical model was elaborated, which estimated the flow of the solution injected satisfactorily at various points of injecting system. The proposed model had better performance for the piston regulations of 20, 30 and 40 mm. For the regulation of 10 mm, good correlation was not obtained among the estimated and observed values of injection flow.
quimigation; injector mechanisms; mathematical model
