Pipeline Aeration Effects on Hydraulic Performance of Rotary Deflection Sprinklers: A Multi-Criteria Optimization Approach

To investigate whether pipeline aeration can enhance the hydraulic performance of sprinkler irrigation systems and thereby support precision agriculture, we developed a programmable logic controller (PLC)-based platform capable of delivering six aeration rates under five starting pressure levels to form a comprehensive test matrix. Key hydraulic parameters, including working pressure, flow rate, irrigation intensity, spray uniformity, and droplet kinetic energy, were systematically evaluated. The results demonstrated that pipeline aeration alters the pressure–flow dynamics, modulates droplet characteristics, and influences energy dissipation. High aeration rates combined with optimized pressure significantly improved irrigation uniformity while reducing excessive spray intensity and mitigating the risk of surface runoff. A multi-criteria evaluation using entropy-weighted TOPSIS identified the H4A6 condition (0.25 MPa, 1.86×10⁻³ m³·s⁻¹) as the optimal operating point. This study confirmed that pipeline aeration can effectively enhance sprinkler hydraulic performance and provides a novel approach for optimizing sprinkler irrigation systems.