Performance Evaluation of Tillage Knife Discharge Microchannel

Liquid mineral fertilizers (LMF) have a high sorption ability, can be metered precisely, and the intra-soil application of LMF is relevant. However, the agricultural equipment for this process that introduces the liquid fertilizer under processed soil layer in the form of a wide band has not yet been proposed. The purpose of the study is to evaluate the performance of a 102 mm wide rectangular discharge microchannel of the proposed soil tillage knife designed for deep tillage and intra-soil application of liquid fertilizers and to study the influence of the microchannel length (L) and slot height (h) on the uniformity of discharge. Solidworks Flow Simulation^® was used during investigations, and simulation results were compared with experiment results. It has been determined that the effective slot height for water discharge at V_i = 3–4 m·s⁻¹ is 0.1 (±0.01) mm, an effective microchannel length is 20 (±2) mm, and the influence of L depends on h. Sheet thickness will not change at a distance of 10–15 mm (b). Fall angle is 0–5°. In conclusion, the proposed discharge microchannel with asymmetrical feed is applicable for intra-soil application of LMF, and the surface tension effect has to be considered. A way to enhancing the sheet uniformity is the geometrical modification of feed channel shape.