Flux Control Methodology for Optimum Fertilization Based on Differential Pressure Fertilization Device

Abstract

Differential pressure fertilization devices are applied widely in cultivated areas. The device suffers from local insufficient or excessive fertilization, which causes environmental pollution and decreases grain production. A flux control methodology is proposed to maintain optimum fertilization for the device based on fertilizer continuity equation. The fertigation flux is constant in the proposed methodology, and the target fertilizer concentration decreases linearly in the device to maintain the optimum fertilization from the fertigation system inlet. The methodology is applied directly for fertilizer in the case of a large dispersion coefficient when the mixture of water and fertilizer is immediate and uniform. An extra parameter is required, and a simple predictor-corrector method is suggested for fertilizer in case of small dispersion coefficient. A grade regulation method is suggested for convenient application of the methodology. A developed numerical model was applied to verify the methodology’s feasibility for optimum fertilization. The numerical model simulates the mixing of water and fertilizer fairly well for different fertilizer dispersion coefficients and indicates the applicability of the flux control methodology. The flux control methodology well simulates optimum fertilization, and both the simple predictor-corrector method and the grade regulation method have the potential to improve the performance of fertigation application based on differential pressure fertilization device.