An analytical solution was developed in this research to predict and evaluate the performance of fertilizer injectors. The conservation equations for mass, momentum and energy were applied to the mixing process between the driving and suction fluids through a dimensionless formulation. High performance injectors were evaluated experimentally using water both as driving and suction fluids in order to determine the head-loss coefficients for each component of these accessories through calibration. The proposed solution presented excellent agreement with the experimental data and achieved adequate values for the implicit head-loss coefficients in the equations. Theoretical efficiency curves generated on the basis of these coefficients showed that the higher the density of the suction fluid, the lower the ranges of flow ratio and efficiencies reached.
fertigation; chemigation; efficiency; analytical solution